Case Title: State v. Copes

Citation: 

Docket Number: 84/16

State: maryland

Court: Maryland Supreme Court

Date: 2017-07-28T00:00:00Z

Document:
State of Maryland v. Robert L. Copes, Jr. 
No. 84, September Term 2016 
 
 
Search and Seizure – Warrant Requirement – Exclusionary Rule – Good Faith 
Exception.  Police officers applied for court authorization to use a cell site simulator and 
other techniques to locate a missing cell phone associated with a murder victim in the hope 
that the phone would lead them to the murderer.  They obtained a court order, based in part 
on the procedure required for obtaining court authorization for a pen register under the 
Maryland Pen Register Statute, Maryland Code, Courts & Judicial Proceedings Article, 
§10-4B-01 et seq.  Using the cell site simulator, the police succeeded in locating the cell 
phone, together with Respondent Robert L. Copes, Jr., and evidence linking him to the 
victim and the murder.  The Circuit Court later concluded that the use of the cell site 
simulator violated the Fourth Amendment and suppressed the evidence.  The Court of 
Appeals assumed, for the sake of argument, that use of a cell site simulator by law 
enforcement officers is a search for purposes of the Fourth Amendment.  The Court 
concluded that, even if the court order under the Pen Register Statute fell short of a search 
warrant, the officers engaged in “objectively reasonable law enforcement activity” in 
obtaining the order and using the cell site simulator to locate the cell phone.  Under the 
good faith exception to the exclusionary rule, the evidence would not be suppressed. 
 
 
 
Circuit Court for Baltimore City 
Case 114090005 
Argument:  April 3, 2017 
IN THE COURT OF APPEALS 
OF MARYLAND 
 
No. 84 
 
September Term, 2016 
 
 
STATE OF MARYLAND 
 
V. 
 
ROBERT L. COPES, JR. 
 
_____________________________________ 
 
 
 
 
Barbera, C.J. 
 
 
 
Greene 
 
 
 
Adkins 
 
 
 
McDonald 
 
 
 
Watts 
 
 
 
Hotten 
 
 
 
Getty, 
 
 
 
 
 
JJ. 
 
______________________________________ 
 
Opinion by McDonald, J. 
Greene, Adkins, and Hotten, JJ., dissent. 
 
______________________________________ 
 
Filed: July 28, 2017 
  
 
Advances in personal technology, like the cell phone, empower individual users but 
may also threaten personal privacy.  When police make use of the features of that 
technology to solve crime, courts and lawyers sometimes struggle to devise ground rules 
that respect constitutional privacy protections.  This case involves an example of the law’s 
effort to keep apace. 
Detectives investigating the gruesome murder of a young homeless woman in 
Baltimore City determined that a cell phone associated with her – but not found with her 
body – was still in active use.  Hoping to find the phone – and the murderer – they applied 
to the Circuit Court for authorization to use, among other techniques, a “cellular tracking 
device” to locate the phone.  They presented a sworn application to the Circuit Court that 
summarized the investigation of the murder, information concerning the missing phone, 
and their purpose in attempting to find it, as well as a draft order that tracked the application 
in pertinent respects.  They did so under an established procedure – approved by the State’s 
Attorney and the Police Department’s lawyer – that had been adapted from a statute for 
police use of devices that record the numbers of incoming and outgoing calls concerning a 
target phone.  The court issued the order, finding that “probable cause exists” upon the 
basis of the application.  
The detectives then employed a device known as a cell site simulator – basically, an 
undercover cell tower – which led them to the apartment of Respondent Robert L. Copes, 
where they found the phone, Mr. Copes, and evidence linking him to the victim and the 
murder.
2 
 
After charges were filed, Mr. Copes asked the Circuit Court to suppress the evidence 
obtained as a result of the use of the cell site simulator.  Despite finding that the detectives 
acted “in good faith” and had done “fine work,” the Circuit Court felt constrained by a 
recent decision of the Court of Special Appeals.1   It granted the motion on the ground that 
the use of the cell site simulator to locate the phone was a search for purposes of the Fourth 
Amendment and that the court order did not function as a search warrant. 
We hold that the evidence need not be suppressed.  Regardless of whether use of a 
cell site simulator is a search for purposes of the Fourth Amendment or whether the court 
order authorizing its use fell short of a search warrant, the detectives in this case acted in 
“objectively reasonable good faith.” 
I 
Background 
A. 
Cell Site Simulators and Judicial Authorization for Location Tracking 
 
1. 
Cell Phones and Location Tracking 
 
The ubiquitous cell phone has become a necessity of modern life.  It facilitates 
mobility and access to information, not to mention mobile access to information.  It has 
also spawned much attention in the application of the constitutional protections of personal 
privacy.  Much of that attention concerns the information contained on a cell phone, 
                                              
1 State v. Andrews, 227 Md. App. 350 (2016). 
3 
 
particularly a “smart phone” that may contain or access a library of private information.2  
Of equal concern is the ability of the cell phone to transmit information about its location 
– and the location of the individual who possesses it.   
 
A cell phone’s identification of its location is one of its essential virtues.  A cell 
phone must be found by a service provider for it to be used as a phone.  The location 
tracking feature of a cell phone is commonly used by those with a cell phone to navigate,3 
to locate an errant cell phone,4 to find friends or family with cell phones in the vicinity,5 
and to summon help to the location of the cell phone in an emergency.6 
                                              
2 See Riley v. California, ___ U.S. ___, 134 S.Ct. 2473 2489-91 (2014); Sinclair v. 
State, 444 Md. 16 (2015). 
3 Without the location tracking function, a cell phone could not offer real-time 
navigation.  Aggregation of such data from many cell phones allows various navigation 
applications to provide traffic updates. 
4 See, e.g., James Bruce, “How to Use Find My iPhone to Get Your Stolen iPhone 
Back” (November 6, 2011).  http://www.makeuseof.com/tag/find-iphone-stolen-iphone/  
[https://perma.cc/8E3N-S7SH]. 
5 A number of cell phone applications use the location tracking features of cell 
phones to inform a cell phone user when friends or acquaintances with cell phones happen 
to be in his or her geographic vicinity.  For example, such a feature is built into the maps 
function in Snapchat.  See Kurt Wagner, “How to Use – and How to Keep Yourself Hidden 
from – Snapchat’s New Maps Feature,” (July 6, 2017).  https://www.recode.net/ 
017/7/6/15929952/how-to-use-hide-ghost-mode-snapchat-snap-maps-location-privacy.  
[https://perma.cc/5PFR-85NU]. 
6 The Federal Communications Commission is requiring wireless service providers 
to provide precise location information of cell phones to public safety agencies in 
connection with 911 calls.  See https://www.fcc.gov/consumers/guides/911-wireless-
services  [https://perma.cc/FZ3J-WMAV].  
4 
 
 
Law enforcement has sought to enlist this feature of cell phones to prevent and 
investigate crime.  This case involved the use of two techniques that depend on a cell 
phone’s indication of its location:  cell site location information obtained from a service 
provider and a device known generically as a cell site simulator. 
 
Cell Site Location Information (“CSLI”) 
 
When a cell phone sends or receives a call or text message, it attempts to connect 
with the service provider’s closest cell tower.7  If one knows which cell towers a cell phone 
has connected to (or is connecting to) and the physical location of those towers, one can 
approximate the geographical location of that cell phone.  This information is often referred 
to as “cell site location information” or “CSLI.”  Information concerning which towers a 
cell phone has connected to in the past is sometimes referred to as “historical CSLI.”  
Information concerning which towers a cell phone is currently connecting to is sometimes 
referred to as “real-time CSLI.”8 
 
Cell Site Simulators 
A cell site simulator works as its name suggests – it pretends to be a cell tower on 
the network of the target phone’s service provider.9  It takes advantage of the fact that a 
                                              
7 See State v. Payne, 440 Md. 680, 691-97 (2014). 
8 A service provider may collect CSLI passively as part of its normal business 
operations.  A provider may also actively monitor the location of a phone on its network 
by “pinging” a phone.  See S. K. Pell & C. Soghoian, Can You See Me Now?:  Towards 
Reasonable Standards for Law Enforcement Access to Location Data That Congress Could 
Enact, 27 Berkeley Tech. L. J. 117, 131-32 (2012). 
9 The various versions of cell site simulators have apparently been given names by 
their manufacturers – such as “Stingray” and “Triggerfish.”  The model of cell site 
5 
 
cell phone – when turned on –constantly seeks out nearby cell towers, even if the user is 
not making a call.10  Furnished with identifying information concerning the target phone, 
the cell site simulator searches for that phone.  When the cell site simulator is close enough, 
the target phone will connect to it as though it were a cell tower.11   
Law enforcement officers using a cell site simulator may employ two devices in 
tandem:  one stationed in a vehicle, the other carried by hand.  The vehicular device, when 
it makes a connection with the target phone, points the user in the direction of the target 
phone.  The handheld device, when taken in that direction, informs the user whether the 
target phone is getting closer or farther away.  The combination of the two devices can 
produce a fairly accurate estimate of the target phone’s location.12   
                                              
simulator used in this case was called “Hailstorm” and was manufactured by the Harris 
Corporation.  We understand that, for purposes of this opinion, any technological 
differences among these models are insignificant. 
10 See Staff of House Committee on Oversight and Government Reform, 114th 
Cong., Law Enforcement Use of Cell-Site Simulation Technologies: Privacy Concerns and 
Recommendations 
(2016) 
at 
10 
, 
https://oversight.house.gov/wp-
content/uploads/2016/12/THE-FINAL-bipartisan-cell-site-simulator-report.pdf 
[https://perma.cc/AF7C-465V].  
11 Other cell phones in that range may or may not also attempt to connect with the 
cell site simulator.  However, because the cell site simulator has been programmed to look 
only for the target phone, the cell site simulator declines to maintain a connection with 
those phones.   
12 It also may be possible to configure particular cell site simulators to intercept data 
or communications.  See generally S. K. Pell & C. Soghoian, A Lot More Than a Pen 
Register, and a Lot Less Than a Wiretap: What the StingRay Teaches Us About How 
Congress Should Approach the Reform of Law Enforcement Surveillance Authorities, 16 
Yale J.L. & Tech. 134, 146 (2013).  According to testimony at the hearing in this case, the 
cell site simulator used in this case did not have that capability.  
6 
 
2. 
Orders Authorizing Location Tracking under the Pen Register Statute 
 
At the time of the investigation in this case, no statute specifically addressed the use 
of a cell site simulator or other device to track a cell phone’s location.13  Apparently, many 
law enforcement agencies, including the Baltimore City Police Department and the United 
States Department of Justice,14 obtained judicial authorization to use a cell site simulator 
by following the established procedures for obtaining authorization to use a pen register or 
trap and trace device.  As we shall see, some modifications and enhancements were made 
to a standard pen register application and order to customize those documents to a cell site 
simulator.  We take a short detour to describe the Maryland Pen Register Statute, Maryland 
Code, Courts & Judicial Proceedings Article (“CJ”), §10-4B-01 et seq.  
In simple terms, a pen register records the numbers dialed out from a given phone, 
and a trap and trace device records the numbers that dial into that phone.  See CJ §10-4B-
01(c), (d) (definitions of “pen register” and “trap and trace device”).  When information 
from both devices is aggregated, a log of all incoming and outgoing calls can be created 
for the period that the devices are active.  These devices do not capture the content of 
                                              
13 A statute was later enacted.  See Part I.A.3 of this opinion below. 
14 See U.S. Dep’t of Justice, Electronic Surveillance Manual; Procedures; Case Law 
46, 
https://www.justice.gov/sites/default/files/criminal/legacy/2014/10/29/elec-sur-
anual.pdf [https://perma.cc/SC85-EHL7].  In 2015, however, the Department changed that 
policy to require federal law enforcement officers to obtain a warrant before using a cell 
site simulator.  U.S. Dep’t of Justice, Justice Department Announces Enhanced Policy for 
Use of Cell site Simulators (Sept. 3, 2015), https://www.justice.gov/opa/pr/justice-
department-announces-enhanced-policy-use-cell site-simulators [https://perma.cc/KX4S-
HFP2]. 
7 
 
communications.  The Fourth Amendment does not require law enforcement officers to 
obtain a search warrant in order to use a pen register or trap and trace device.  Smith v. 
Maryland, 442 U.S. 735 (1979).15  Nevertheless, the General Assembly, by enacting the 
Pen Register Statute,16 has required law enforcement officers to obtain judicial approval 
before using a pen register or a trap and trace device in an investigation.17 
 
To obtain an order under the Pen Register Statute, a law enforcement officer must 
make application under oath to a “court of competent jurisdiction in the State.”  CJ §10-
4B-03(a).  The application must identify the officer and agency conducting the 
investigation, and must state that the information likely to be obtained is relevant to an 
ongoing criminal investigation being conducted by that agency.  CJ §10-4B-03(b).  Unlike 
an application for a search warrant, the application to use a pen register or trap and trace 
device need not demonstrate probable cause that a crime has been committed or that the 
                                              
15 In Smith, the Supreme Court held that a telephone user has no legitimate 
expectation of privacy in numbers dialed from the user’s phone, because the user 
voluntarily shares those numbers with a third party – i.e., the telephone company.  The 
Court held that law enforcement use of a pen register to record those numbers is not a 
Fourth Amendment search and, correspondingly, does not require a warrant.  That 
reasoning has come to be known as the “third party doctrine.” 
Although the Supreme Court has never decided whether the use of a trap and trace 
device is a Fourth Amendment search, lower courts applying the third party doctrine have 
held that use of trap and trace device is not a search and that a warrant is not required.  See, 
e.g., United States v. Hallmark, 911 F.2d 399, 402 (10th Cir. 1990); United States v. Reed, 
575 F.3d 900, 914 (9th Cir. 2009); Sun Kin Chan v. State, 78 Md. App. 287 (1989). 
16 This statute governs the use of trap and trace devices, as well as pen registers. 
17 There is a parallel federal statute.  18 U.S.C. §3121 et seq.   
 
8 
 
evidence relating to that crime will be acquired through use of the device.  If the application 
is approved, the order must identify the individual, if known, whose phone number is being 
surveilled and the individual who is the subject of the criminal investigation.  CJ §10-4B-
04(b).  The order may authorize use of the device for a maximum of 60 days.  CJ §10-4B-
04(c).  The statute also requires a phone service provider to whom an order is presented to 
furnish the officer with “all information, facilities, and technical assistance necessary to 
accomplish the installation” of the device “unobtrusively and with a minimum of 
interference” to the phone’s service.  CJ §10-4B-05(a)-(b).   
3. 
CP §1-203.1 
In 2014, the General Assembly enacted a statute to provide a specific judicial 
procedure to authorize law enforcement use of location tracking through cell phones. 
Chapter 191, Laws of Maryland 2014, codified at Maryland Code, Criminal Procedure 
Article (“CP”), §1-203.1.  That statute provides for the District Court or a circuit court to 
authorize law enforcement officers “to obtain location information from an electronic 
device” in defined circumstances if the officers present a sworn application with a showing 
of probable cause, as specified in the statute.  The statute became effective October 1, 2014, 
a few months after the events in this case.  Since that time, law enforcement efforts to 
obtain judicial authorization for use of a cell site simulator presumably have been made 
pursuant to CP §1-203.1, as opposed to the format based on the Pen Register Statute.  No 
appellate court has yet construed this statute or opined on its constitutionality. 
 
 
9 
 
B. 
The Investigation of the Murder of Ina Jenkins 
 
The following information was elicited in testimony at the pretrial motions hearing 
in this case.  For purposes of deciding the issues before us, it appears to be largely 
undisputed. 
1. 
The Homicide 
On February 4, 2014, a burned body was found in the rear yard of 4013 Penhurst 
Avenue, a vacant home in northwest Baltimore.  Police found a black backpack containing 
a plastic bottle with some gasoline in a crawl space of the house about 10 to 15 feet from 
the body.  Detective Bryan Kershaw of the homicide unit of the Baltimore City Police 
Department was assigned as lead investigator.   
2. 
The Investigation 
Identification and Autopsy 
Fingerprint evidence identified the body as that of Ina Jenkins, a 34-year old 
homeless woman.  The State Medical Examiner performed an autopsy and determined that 
Ms. Jenkins’ death was a homicide by blunt force trauma and that her body had been burned 
after she died.  Based on evidence gathered from the crime scene and elsewhere, Detective 
Kershaw suspected that Ms. Jenkins had been murdered at a nearby location and that her 
body had been bound, carried on foot to the yard of the vacant home, and set on fire 
sometime on January 20 or 21, 2014 – approximately two weeks before her body was 
discovered. 
 
 
10 
 
Videos of Ms. Jenkins with an Unidentified Man 
Detective Kershaw learned that Ms. Jenkins frequently spent her days at My Sister’s 
Place, a resource center for women and children in need run by Catholic Charities in 
downtown Baltimore, and at the Enoch Pratt Free Library across the street.  She often spent 
her nights at what was called a “code blue” shelter.18  Detective Kershaw obtained records 
of recent expenditures Ms. Jenkins had made with her Independence Card – a debit card 
for food stamps and other cash benefits – and obtained surveillance videos from those 
merchants.  Videos from two different merchants showed Ms. Jenkins and an unidentified 
man shopping a few days before her death.  In both videos, the man was wearing, in 
Detective Kershaw’s words, a “very distinct” blue and yellow coat.  Detective Kershaw 
also obtained records of books Ms. Jenkins had recently borrowed from the library.  
Canvassing the Neighborhood of the Murder 
During the week beginning Monday, February 10, 2014, detectives canvassed the 
Penhurst Avenue neighborhood during the day and night to find potential witnesses to the 
murder.  Still photos from the surveillance videos were given to officers on patrol in the 
area in the hope that an officer might encounter and recognize Ms. Jenkins’ unidentified 
companion – or, perhaps, his “very distinct” coat.  
                                              
18 When the Baltimore City Health Commissioner declares a “code blue” alert 
during periods of extreme cold weather, various steps are taken to extend the hours and 
capacity of homeless shelters.  See Baltimore City Health Department, Code Blue Alert 
Information, http://health.baltimorecity.gov/emergency-preparedness-response/code-blue 
[https://perma.cc/RK35-QLKP]. 
11 
 
During these canvasses, Detective Kershaw knocked on various doors in the 
neighborhood, including the doors to apartments 1-E and 1-W on the first floor of 4014 
Penhurst Avenue, an apartment building directly across the street from the vacant home 
with the yard where Ms. Jenkins’ body was found.  On February 12, 2014, Detective 
Kershaw met with the tenant in apartment 1-W.  That tenant advised Detective Kershaw 
that, although the second floor apartment in the building was vacant, apartment 1-E was 
occupied.  There was no response when Detective Kershaw knocked on the door to 
apartment 1-E that day. 
Telephones used by Ms. Jenkins 
 
Detective Kershaw also interviewed Ms. Jenkins’ mother, who provided several 
telephone numbers associated with her daughter.  In a letter, Ms. Jenkins had provided her 
mother with a phone number ending in -8138.  More recently, on January 19, 2014, a day 
or two before the murder, Ms. Jenkins had called her mother from another phone number, 
ending in -4686, according to the caller ID log in her mother’s telephone.  Neither phone 
had been found with Ms. Jenkins’ body.  The detectives decided to try to locate the phones 
in the hope that they would advance the investigation. 
 
Court Order under the Pen Register Statute 
 
On February 11, 2014, one of the detectives applied to the Circuit Court for 
Baltimore City for court orders related to the -8138 and -4686 numbers.19  We shall focus 
                                              
19 Ms. Jenkins’ mother had also provided a third phone number to Detective 
Kershaw.  Detective Kershaw determined that the phone associated with the third number 
was out of service and therefore did not seek an order with respect to it. 
12 
 
on the order pertaining to the -4686 number, as that is the particular order that led to the 
discovery and apprehension of Mr. Copes and that is at issue in this case.   
 
The sworn application was submitted under the Pen Register Statute.  The 
application asked the court to authorize the “installation and use of a device known as a 
Pen Register/Trap & Trace and Cellular Tracking Device to include cell site information.”  
In “support of probable cause for the interception of real-time cell site information,” the 
detective provided a brief summary of the discovery of Ms. Jenkins’ body and the results 
of the autopsy, reported that certain cell phone numbers were associated with Ms. Jenkins 
but that the phones associated with those numbers were not found with her body, and 
concluded that the phones were taken by the “unknown suspect(s) and were likely being 
used “until service is terminated or the phone becomes non-functional.”  The detective 
further asserted in the application that “records will assist in possibly identifying and 
locating the unknown suspect(s)” and that “the information likely to be obtained 
concerning the aforesaid individual’s location will be obtained by learning the numbers, 
locations, and subscribers of the telephone number(s) being dialed or pulsed from or to the 
aforesaid telephone and that such information is relevant to the ongoing criminal 
investigation being conducted by [the Police Department].”   
The application asked for an order directing cell phone service providers to provide 
necessary technical information to the police and asked the court for authorization to, 
among other things, “employ surreptitious duplication of facilities, technical devices or 
equipment to accomplish the use of a … Cellular Tracking Device, unobtrusively and with 
a minimum of interference to the subscriber of the … telephone, and … initiate a signal to 
13 
 
determine the location of the subject’s mobile device on the service provider’s network or 
with such other reference points as may be reasonably available, Global Position system 
Tracing and Tracking, Mobile Locator tools, R.T.T. (Real Time Tracking Tool), 
…Precision Locations and any and all locations …” 
 
The Circuit Court issued the order the same day.  In the order, the court found “that 
probable cause exists and that the applicant has certified that the information likely to be 
obtained . . . is relevant to an ongoing criminal investigation.”  The order authorized the 
installation and use of a “Pen Register/Trap & Trace and Cellular Tracking Device to 
include cell site information” for 60 days within the jurisdiction of the court, and also 
authorized the Police Department to obtain information about the cell phones from the 
pertinent service provider.  Most pertinent to this case, the order authorized the detectives 
to “employ … [a] Cellular Tracking Device [and] initiate a signal to determine the location 
of the subject’s mobile device on the service provider’s network or with such other 
reference points as may be reasonably available, Global Position System Tracing and 
Tracking, Mobile Locator tools, R.T.T. (Real Time Tracking Tool)….” with the same 
conditions and qualifications as requested in the application.  In addition, the service 
provider was directed to “initiate a signal to determine the location of the subject’s mobile 
device on the service provider’s network or with such other reference points as may be 
reasonably available and at such intervals and times as directed by the law enforcement 
agent/agencies serving this order.” 
 
 
14 
 
 
Calling the Cell Phone 
The detectives determined from the service provider – in this case Verizon – that 
the -4686 phone was a prepaid phone without an annual contract and that therefore there 
was no subscriber information available for that phone.  Detective Kershaw called 
the -4686 number daily, without success until February 18, 2014, when a male voice 
answered the phone.  Detective Kershaw hung up without speaking to the individual and 
immediately contacted Detective John Haley of the Police Department’s Advanced 
Technical Team.   
 
Obtaining CSLI for the Cell Phone 
 
Pursuant to the court order, Detective Haley obtained from Verizon a list of calls 
and text messages sent or received by the -4686 phone.  That list, which began with records 
starting around 7:30 p.m. that day, was created by Verizon and was updated in real time.  
In addition to noting the calls and text messages, the list also included CSLI – information 
concerning which cell towers the phone was connected to for each call and text message, 
as well as which area or “sector” of each tower’s coverage the cell phone was using.  
 
The list of calls and text messages made by the -4686 phone indicated that the phone 
was using two cell towers in Baltimore, one located at 2500 West Belvedere Avenue and 
the other at 4110 Menlo Drive.  Combining that information with information about which 
sector of each tower’s coverage the phone was using, Detective Haley and the Advanced 
Technical Team were able to trace the -4686 phone to the Penhurst Avenue neighborhood, 
where Ms. Jenkins’ body had been found.  
 
15 
 
 
Using the Cell Site Simulator 
After analyzing the CSLI and determining that the -4686 phone was in the Penhurst 
Avenue neighborhood, Detective Haley and the team, under directions from Detective 
Kershaw, drove a cell site simulator to that area.  The cell site simulator consisted of two 
devices, one stationed in the Advanced Technical Team’s police vehicle and a handheld 
device.  The detectives punched into the cell site simulator the -4686 phone’s identifying 
numbers, which they had obtained from Verizon pursuant to the court order.   Detective 
Haley and the team then used the devices to narrow down the cell phone’s location.   
 
Using the vehicular device, Detective Haley and the Advanced Technical Team 
were able to make signal contact with the -4686 phone.  The team then contacted Detective 
Kershaw, who came to the scene.20  After his arrival, the detectives again used the cell site 
simulator – both the vehicular and the handheld devices – to track the -4686 cell phone.  
The devices indicated that the phone was at 4014 Penhurst Avenue – the apartment building 
across the street from the yard where Ms. Jenkins’ body had been found and where 
Detective Kershaw had already questioned the residents other than the occupant of 
apartment 1-E.21  
                                              
20 When Detective Kershaw first arrived at 4014 Penhurst Avenue, he saw an 
individual, later identified as Perry Renwick, emerging from the back of that building.  
Detective Kershaw identified himself as a police officer, but Mr. Renwick fled back up the 
stairs.  Detective Kershaw pursued him to a third floor apartment that was previously 
unknown to the detectives.  Detective Kershaw spoke briefly with Mr. Renwick and noted 
that he was not the individual in the surveillance videos with Ms. Jenkins.  
21 The record is unclear as to whether the device allowed police to track the phone 
to a specific apartment or just to 4014 Penhurst Avenue generally.  In any event, by the 
time Detective Kershaw arrived at the door to apartment 1-E that night, he had already met 
16 
 
Meeting Mr. Copes 
At approximately 11:30 pm, Detective Kershaw knocked on the door to apartment 
1-E, as he had earlier in the week.  This time, the door was answered by Mr. Copes, clad 
in a t-shirt and boxer shorts.  Detective Kershaw immediately recognized Mr. Copes as the 
man who had been accompanying Ms. Jenkins in the surveillance videos.  He showed Mr. 
Copes a photo of Ms. Jenkins and explained that the Police Department was investigating 
her death.  Mr. Copes said that he knew Ms. Jenkins from the “code blue” shelter.   
Mr. Copes indicated that he wished to get dressed and the two men went into the 
apartment.  As he entered, Detective Kershaw observed hanging on a vacuum cleaner a 
“very distinct” blue and yellow coat that was similar to the coat worn by the man with Ms. 
Jenkins in the surveillance videos.  Once inside the apartment Detective Kershaw also 
observed several bottles of cleaning agents, a portion of the floor where the carpet had been 
ripped up, and bleach spots on the remaining carpet.  
After some further conversation with the detectives at the apartment, Mr. Copes 
agreed to go to the police station.  At the station, Mr. Copes was given Miranda warnings 
and spoke further with the police.22 
 
                                              
the inhabitants of the other units in the building and determined that none of them were the 
man in the video.   
22 In an affidavit supporting a subsequently-issued search warrant, Detective 
Kershaw reported that Mr. Copes stated that he had known Ms. Jenkins for some time, but 
that she had never been inside his apartment. 
17 
 
Search Warrants 
Early the next morning, February 19, 2014, Detective Kershaw applied to the 
District Court sitting in Baltimore City for a warrant to search Mr. Copes’ apartment as 
well as a warrant to obtain a sample of Mr. Copes’ DNA.  Among the items retrieved during 
the search of the apartment were swabs of suspected blood that were later matched to Ms. 
Jenkins through DNA testing.   
Some weeks later, upon reviewing the photos of Mr. Copes’ apartment taken during 
the execution of the February 19, 2014 warrant, Detective Kershaw noticed a book sitting 
on Mr. Copes’ desk in one of the photos.  The title – Spelling the Easy Way – matched a 
library book that Ms. Jenkins had checked out of the Enoch Pratt Free Library shortly 
before her death.  On April 7, 2014, Detective Kershaw applied for and obtained another 
search warrant for Mr. Copes’ apartment.  During the execution of this second warrant, the 
library book was retrieved from Mr. Copes’ apartment. 
C. 
Legal Proceedings 
1. 
Charges 
 
On March 31, 2014, Mr. Copes was indicted by a grand jury in Baltimore City and 
charged with first-degree murder and with wearing and carrying a dangerous weapon in 
violation of Maryland Code, Criminal Law Article, §4-101.   
2. 
Motion to Suppress 
 
Mr. Copes moved to suppress all evidence recovered from his apartment as well as 
his statements to police.  He asserted that the Police Department’s use of a cell site 
simulator was a warrantless and unreasonable search in violation of the Fourth Amendment 
18 
 
and that the evidence gathered as a result of the use of that device, including his identity 
and his statements to police, was the fruit of that illegal search.   
The Circuit Court conducted a hearing on Mr. Copes’ motion on April 25, 2016.  At 
the hearing, Detective Haley and Detective Kershaw testified in detail about the techniques 
used by the Advanced Technical Team to track the -4686 cell phone to 4014 Penhurst 
Avenue.  Both detectives also testified about the protocols followed in applying for the 
court order before the cell site simulator was used.  
 
According to the detectives, the form of the application had been drafted and 
approved by the State’s Attorney’s Office and the Police Department’s legal department, 
had been used since 2007, and was not revised until late 2014, after the investigation in 
this case.  Detective Kershaw testified that he was not aware of any “issues” with the 
application, which had been used and approved “many, many times.”  In his experience, 
up through the time he applied for the orders at issue in this case, the application had, in 
fact, never been denied, nor had there “ever been any reservation expressed by [any judge 
of the Circuit Court for Baltimore City] as it relates to . . . the validity of those orders” 
obtained via the application.  
Both detectives testified that they believed that the orders in this case authorized 
them to use the cell site simulator to locate the -4686 phone.  Detective Haley said that he 
assumed that, if the judge to whom the application and draft order was presented had not 
thought them to be sufficient, the judge would not have signed the order.  Although another 
detective had applied for the order in this case, Detective Haley testified that, had he been 
the one submitting the applications, he would have answered any of the judge’s questions.  
19 
 
Detective Haley conceded that, at that time, there was a nondisclosure agreement between 
the Police Department and the FBI that ostensibly prevented disclosure of certain 
information about the cell site simulator.   
Mr. Copes also testified briefly at the hearing to establish his standing to seek 
suppression of the evidence obtained through the cell site simulator.  He stated that he was 
the owner of the -4686 phone.  On cross-examination, he stated that he had let a “dear 
friend” named Ina use the phone.   
3. 
Circuit Court Ruling 
 
The Circuit Court granted Mr. Copes’ motion to suppress.  The court explained its 
reasoning in an oral opinion that relied heavily on the then-recent decision of the Court of 
Special Appeals in State v. Andrews, 227 Md. App. 350 (2016), that had affirmed a circuit 
court decision suppressing evidence derived from use of a cell site simulator.23  The Circuit 
Court stated its belief that “these police officers acted in good faith” and noted some 
distinctions from the facts in Andrews – in Andrews the police used the device to find the 
known cell phone of a known suspect while in this case the suspect was unknown and the 
police believed the phone belonged to the victim.  Nevertheless, the court felt bound to 
follow the decision in Andrews. 
The Circuit Court also considered whether the police would have inevitably 
discovered Mr. Copes without use of the cell site simulator, and opined that “this case is a 
                                              
23 The Andrews decision is discussed in greater detail below.  See Part II.B.2-3 of 
this opinion. 
20 
 
much closer call than Andrews.”  However, it reasoned that, even if the detectives had 
eventually found Mr. Copes at 4014 Penhurst Avenue, it might have been at a later time 
when the incriminating evidence in the apartment was gone.  The court also rejected an 
argument that the pen register and other CSLI data (apart from the use of the cell site 
simulator) would have independently led the detectives to Mr. Copes, noting that the CSLI 
data “didn’t pinpoint this particular location.”  
The court reiterated its finding that “these officers operated in good faith,” but held 
that the use of the cell site simulator without a warrant was an unconstitutional search.  As 
a result, it held that evidence derived from that search – all evidence seized from Mr. 
Copes’ apartment as well as his statements to police – should be suppressed as fruit of an 
illegal search.  The State appealed. 
4. 
Appeal to Court of Special Appeals 
 
In an unpublished opinion issued October 25, 2016, the Court of Special Appeals 
affirmed the Circuit Court ruling.  Citing its previous decision in Andrews, the intermediate 
appellate court held that the use of the cell site simulator was a Fourth Amendment search 
and that the order based on the Pen Register Statute was not a constitutionally-sufficient 
authorization for that search.  It also rejected the State’s arguments as to why the 
exclusionary rule should not be applied.  It held that the discovery of Mr. Copes – and the 
evidence in his apartment – was not inevitable or sufficiently attenuated from the use of 
the cell site simulator to avoid application of the exclusionary rule.24  Similarly, it rejected 
                                              
24 Because the State did not raise an attenuation argument in the Circuit Court, the 
Court of Special Appeals held that this argument was waived on appeal.  Nevertheless, the 
21 
 
the State’s argument that the police officers believed, in good faith, that the order 
authorized the use of the cell site simulator, because, when applying for the order, they 
“did not provide clearly what technology [they] sought to use, nor the manner in which the 
technology operated.”    
The State petitioned this Court for a writ of certiorari, which we granted.   
II 
Discussion 
A. 
Standard of Review 
In reviewing a trial court’s decision to grant or deny a motion to suppress evidence 
based on a constitutional violation, we generally accept any fact findings made by the trial 
court unless they are clearly erroneous.  The ultimate question as to whether there was a 
constitutional violation is a legal question on which we accord no special deference to the 
trial court.  See Sinclair v. State, 444 Md. 16, 27 (2015).  Similarly, the application of the 
exclusionary rule – and whether there is an applicable exception to that rule in the particular 
case – is a question of law that we decide without deference to the lower court.  Marshall 
v. State, 415 Md. 399, 408 (2010); see also McDonald v. State, 347 Md. 452, 470 n.10 
                                              
intermediate appellate court concluded that, even if the State had preserved that argument, 
it would be unavailing because (1) the discovery of Mr. Copes in his apartment occurred 
shortly after the detectives used the cell site simulator, (2) Mr. Copes’ decision to allow 
Detective Kershaw into his apartment was a direct result of the use of the cell site simulator, 
and (3) the Police Department and the State’s Attorney’s Office were operating under the 
nondisclosure agreement with the FBI, which the court viewed as an affirmative effort “to 
hide this technology from public and judicial oversight.”  
22 
 
(1997) (ultimate question whether good faith exception to exclusionary rule applies is a 
legal issue).   
B. 
Whether Evidence Obtained by Use of a Cell Site Simulator Should be Suppressed 
The State presents one question for review:  Did the lower courts err in excluding 
the evidence?  The facial simplicity of this single question belies its multi-layered 
complexity.  It can be broken down into three parts:   
(1) Search – Was use of the cell site simulator in this case a search for 
purposes of the Fourth Amendment? 
 
(2) Warrant – If use of the cell site simulator was a search, did the court order 
obtained by the police serve the function of a warrant for purposes of the 
Fourth Amendment? 
 
(3) Exception to Suppression – If the court order was not equivalent to a 
warrant, is there an applicable exception to the warrant requirement or 
to the exclusionary rule that allows for admission of the evidence at trial? 
 
We shall not answer the first two questions.  With respect to the first question, the 
State has conceded, for purposes of this case, that the use of the cell site simulator 
constituted a search.  There is no reason to deviate from the usual rule against providing an 
advisory opinion in order to give a definitive answer to that question, particularly when the 
issue concerns a rapidly changing technology and shifting legal landscape.   
The State does ask us to answer the second question as to the sufficiency of the court 
order as a warrant for purposes of the Fourth Amendment.  This, however, is a close 
question – and one that is not likely to recur, at least with respect to the format of this 
particular order.  As noted earlier, the General Assembly enacted a statute three years ago 
that specifically addresses court orders authorizing law enforcement use of devices such as 
23 
 
cell site simulators.  Presumably any orders issued in the interim have been based on that 
statute.  In any event, it is not necessary to answer this question to resolve this case. 
We will answer the third question.  In particular, we will decide whether the good 
faith exception to the exclusionary rule applies in these circumstances, even if one 
considers use of the cell site simulator to locate a cell phone to be a search and the court 
order in this case inadequate as a warrant.  In doing so, we will discuss factors bearing on 
each of the first two questions, as they affect the assessment of whether the good faith 
exception applies here.  For the reasons set forth below, we conclude that it does.25 
 
1. 
The Exclusionary Rule and the Good Faith Exception 
The Fourth Amendment to the United States Constitution states that “[t]he right of 
the people to be secure in their persons, houses, papers, and effects, against unreasonable 
searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable 
cause, supported by Oath or affirmation, and particularly describing the place to be 
searched, and the persons or things to be seized.”26  To vindicate this guarantee and deter 
violations by law enforcement, the Supreme Court has developed the “exclusionary rule.” 
Under the exclusionary rule, evidence obtained in violation of the Fourth Amendment is 
ordinarily excluded from the criminal trial of a defendant whose rights were violated by an 
                                              
25 Because our resolution of this case turns on the good faith of the officers, we need 
not – and do not – address the State’s arguments on inevitable discovery and attenuation. 
26 This Court has held that the Maryland Constitution provides the same protection 
in Article 26 of the Maryland Declaration of Rights.  See Givner v. State, 210 Md. 484 
(1956); see also D. Friedman, The Maryland State Constitution:  A Reference Guide (2006) 
36-37.  
24 
 
illegal search or seizure.  Weeks v. United States, 232 U.S. 383 (1914) (establishing the 
exclusionary rule in federal courts); Mapp v. Ohio, 367 U.S. 643 (1961) (extending 
exclusionary rule to state courts). 
The exclusionary rule is not itself an individual right; therefore, suppression of 
evidence “is not an automatic consequence of a Fourth Amendment violation.”  Herring v. 
United States, 555 U.S. 135, 137, 141 (2009).  The Supreme Court has cautioned that 
suppression “has always been our last resort, not our first impulse.” Hudson v. Michigan, 
547 U.S. 586, 591 (2006).  The rule’s sole purpose is to deter future Fourth Amendment 
violations by law enforcement.  United States v. Leon, 468 U.S. 897, 916 (1984).  It is to 
be applied only when this “deterrent effect [is] substantial and outweigh[s] any harm to the 
justice system.”  Herring, 555 U.S. at 147; see also United States v. Calandra, 414 U.S. 
338, 348 (1974).  Because the rule imposes a “costly toll upon truth-seeking and law 
enforcement objectives,” those arguing for its application face a “high obstacle.”  
Pennsylvania Bd. Of Probation and Parole v. Scott, 524 U.S. 357, 364 (1998) (internal 
quotations and citations omitted). 
The exclusionary rule is not applied when law enforcement officials engage in 
“objectively reasonable law enforcement activity,” even if that activity is later found to be 
a violation of the Fourth Amendment.  Leon, 468 U.S. at 919.  This exception to the 
exclusionary rule is also known as the “good faith exception” because it depends on 
whether law enforcement officers acted in good faith.  Davis v. United States, 564 U.S. 
229, 238 (2011).  For example, the Supreme Court has held the good faith exception 
applicable when law enforcement officers (1) conducted a search pursuant to a facially 
25 
 
valid search warrant that was later found to lack probable cause,27 (2) conducted a search 
pursuant to a statute authorizing warrantless administrative searches that was later held to 
be unconstitutional,28 (3) made an arrest pursuant to a warrant listed in a judicially-
maintained database that was later revealed to be inaccurate because the warrant had been 
quashed,29 (4) made an arrest pursuant to a warrant listed in a law enforcement-maintained 
database that was later revealed to be inaccurate because the warrant had been recalled,30 
and (5) conducted a search in reliance on binding appellate precedent that was later 
overruled.31  This Court has applied the good faith exception in similar circumstances.32 
The Supreme Court has described four situations in which the good faith exception 
would not be applied:  (1) the magistrate is misled by information in the application for the 
warrant that the officer knew was false or would have known was false, except for a 
reckless disregard for the truth; (2) the magistrate wholly abandons a detached and neutral 
role; (3) the affidavit is so lacking in probable cause so to render official belief in its 
                                              
27 Leon, 468 U.S. 897. 
28 Illinois v. Krull, 480 U.S. 340 (1987). 
29 Arizona v. Evans, 514 U.S. 1 (1995). 
30 Herring v. United States, 555 U.S. 135 (2009). 
31 Davis v. United States, 564 U.S. 229 (2011). 
32 See, e.g., Spence v. State, 444 Md. 1, 10-13 (2015) (applying good faith exception 
where law enforcement officers conducted a search in reliance on binding appellate 
precedent that was later overruled); Patterson v. State, 401 Md. 76, 104-11 (2007) 
(applying good faith exception when law enforcement officers conducted a search pursuant 
to a facially valid search warrant that was later found to lack probable cause).  
26 
 
existence entirely unreasonable; (4) the warrant is so facially deficient, by failing to 
particularize the place to be searched or the things to be seized, that the executing officers 
cannot reasonably presume it to be valid.33   
Relevant to the application of the good faith exception here – and whether the 
suppression of evidence under the exclusionary rule would deter future unlawful conduct  
by investigators – is the extent to which it should have been clear to the detectives in this 
case (1) that the courts would determine that use of a location tracking device like the cell 
site simulator was a search and (2) that a court order in the format similar to that used for 
pen registers and trap and trace orders would be inadequate to authorize use of the device. 
 
2. 
Location Tracking and Fourth Amendment Searches 
Two basic principles governing application of the Fourth Amendment are that it 
“protects people, not places”34 and that a “Fourth Amendment search occurs [only] when 
the government violates a subjective expectation of privacy that society recognizes as 
reasonable.”35  The Supreme Court has reached varying conclusions about the application 
of these principles to the use of location tracking devices, and has recently agreed to 
consider such an issue related to cell phones.  A number of lower courts have discussed the 
Fourth Amendment implications of location tracking by means of CSLI and cell site 
simulators. 
                                              
33 Leon, 468 U.S. at 923; see also Patterson v. State, 401 Md. 76, 104 (2007). 
34 Katz v. United States, 389 U.S. 347, 352 (1967). 
35 Kyllo v. United States, 533 U.S. 27, 33 (2001). 
27 
 
a.  Real-Time Location Tracking Not Involving Cell Phones 
Beepers – to the home v. in the home   
In a pair of cases from the 1980s involving then-contemporary technology, the Court 
reached different conclusions on whether the clandestine use of a radio transmitter – a 
“beeper” – by law enforcement officers to track a suspect or contraband in the suspect’s 
control constituted a search for purposes of the Fourth Amendment.  The difference 
appeared to turn on whether the device tracked movement in a public place or within a 
private dwelling.   
In one case,36 law enforcement officers installed a beeper in a container of chemicals 
purchased by the suspect and then tracked the container as the suspect transported it via 
automobile to the area around a cabin where he operated a drug laboratory.  The Court held 
that the use of the beeper was not a Fourth Amendment search.  The Court observed that, 
by travelling over the public streets, the suspect “voluntarily conveyed to anyone who 
wanted to look the fact that he was travelling over particular roads in a particular direction,” 
and that the beeper was not used to reveal information as to the movement of the container 
within the cabin. The Court concluded that the suspect had no reasonable expectation of 
privacy in the container’s movements.37  
                                              
36 United States v. Knotts, 460 U.S. 276, 277-79 (1983). 
37 Knotts, 460 U.S. at 281, 285.  The defendant did not challenge the physical 
installation of the beeper, only its tracking by law enforcement.  Id. at 279, n.**. 
28 
 
In the other case,38 law enforcement officers installed a beeper in a container of 
chemicals purchased by the suspect and again tracked the container, this time into – and 
not just to the area around – a home.  Unlike the previous case, where the beeper “told the 
authorities nothing about the interior of [the] cabin,” the Court noted that the tracking in 
the second case indicated that the beeper was inside the suspect’s house, “a fact that could 
not have been visually verified.”39  Because individuals have privacy interests in their 
homes, the Court concluded that this tracking was a Fourth Amendment search.40   
GPS trackers – trespass v. reasonableness   
Nearly 30 years later, the Court considered law enforcement use of a Global 
Positioning System (GPS) device to track a suspect for an extended period of time.  In that 
case,41 law enforcement officers attached a GPS device to the suspect’s automobile and 
tracked the vehicle’s movements for 28 days.  The Court unanimously agreed that these 
actions constituted a Fourth Amendment search, but the justices differed on the rationale 
for this conclusion.  A majority of five justices attributed the violation to the fact that the 
officers had committed a common law trespass when they installed the device on the car.42  
The majority opinion declined to delve into the “thorny problems” that might be posed if 
                                              
38 United States v. Karo, 468 U.S. 705, 707-10 (1984).   
39 Id. at 715.   
40 Id. at 718. 
41 United States v. Jones, 565 U.S. 400, 402-03 (2012).   
42 Id. at 404-07 (Scalia, J.) (concluding that the government “physically occupied 
private property for the purpose of obtaining information”).   
29 
 
the tracking involved only the transmission of electronic signals, but noted that such a case 
would be subject to a reasonableness analysis.43  The other four justices would have 
resolved the case by applying a reasonableness test under which short-term monitoring of 
movements on a public street by means of a GPS device would be reasonable as in “accord 
with expectations of privacy that our society has recognized as reasonable” while longer 
term monitoring would violate those expectations.44  Two concurring opinions in Jones 
predicted that advances in personal technology would enhance location tracking 
capabilities, affect expectations of privacy, and raise additional questions under the Fourth 
Amendment.45 
b.  Retrospective Location Tracking via Cell Phone – Historical CSLI 
As described earlier in this opinion, the location of a cell phone can be approximated 
by analyzing service provider records of the cell towers with which the phone connected 
                                              
43 Id. at 411-13. 
44 565 U.S. at 418-30 (Alito, J., concurring in the judgment).  
45 Writing for four justices, Justice Alito noted that “cell phones and other wireless 
devices now permit wireless carriers to track and record the location of users” without a 
physical trespass; that such features are offered to and desired by consumers; and that “the 
availability and use of these and other new devices will continue to shape the average 
person’s expectations about the privacy of his or her daily movements.”  565 U.S. at 428-
29 (Alito, J., concurring in the judgment).  
In a separate concurrence, Justice Sotomayor, who joined the five-justice majority 
subscribing to the trespass theory, warned that “GPS monitoring generates a precise, 
comprehensive record of a person’s public movements that reflects a wealth of detail about 
her familial, political, professional, religious, and sexual associations.”  She nevertheless 
conceded that “the same technological advances that have made possible nontrespassory 
surveillance techniques will also affect the Katz test by shaping the evolution of societal 
privacy expectations.”  565 U.S. at 415 (Sotomayor, J., concurring). 
30 
 
to make and receive calls and text messages.  Appellate courts have reached different 
conclusions as to whether the warrantless collection of historical CSLI implicates the 
Fourth Amendment.  The United States Supreme Court recently agreed to consider whether 
a search warrant is required for law enforcement officers to obtain historical CSLI from a 
service provider.  United States v. Carpenter, ___U.S. ___, 2017 WL 2407484 (June 5, 
2017). 
Most courts have concluded that law enforcement access to historical CSLI is not a 
search for purposes of the Fourth Amendment.  They have cited the “third party doctrine,” 
which the Supreme Court elucidated in concluding that law enforcement officers do not 
conduct a search for purposes of the Fourth Amendment when they request a telephone 
company to install a pen register46 or obtain a depositor’s bank records from a financial 
institution.47  For example, in United States v. Graham, 824 F.3d 421, 427 (2016) (en banc), 
the Fourth Circuit concluded that an individual does not have a reasonable expectation of 
privacy in a cell phone’s historical CSLI.  The Fourth Circuit reasoned that, because a cell 
phone user voluntarily shares that information with third parties – i.e., cell phone service 
providers – whenever the cell phone user makes a call or sends a text message, the user 
cannot reasonably expect it to remain private.  824 F.3d at 427-28.  Accordingly, the 
collection of such data by law enforcement officers is not a Fourth Amendment search.    
                                              
46 Smith v. Maryland, 442 U.S. 735 (1979); see Part I.A.2 of this opinion above. 
47 United States v. Miller, 425 U.S. 435 (1976). 
31 
 
 
Many other federal appellate courts have come to the same conclusion as the Fourth 
Circuit in Graham based on the same reasoning.  See, e.g., United States v. Carpenter, 819 
F.3d 880 (6th Cir. 2016), cert granted, ___U.S. ___, 2017 WL 2407484 (June 5, 2017); 
United States v. Davis, 785 F.3d 498 (11th Cir. 2015) (en banc); In re application of the 
United States for historical cell site data, 724 F.3d 600 (5th Cir. 2013); see Graham, 824 
F.3d at 428-29 & nn.6-7 (collecting cases); see also Zanders v. Indiana, 73 N.E.3d 178 
(Ind. 2017).  
The Third Circuit, however, has reached a different conclusion, and rejected 
application of the third party doctrine to historical CSLI.  In re Application of the United 
States for an Order Directing a Provider of Electronic Communication Service to Disclose 
Records to the Government, 620 F.3d 304, 317 (3rd Cir. 2010).  In that case, the court 
reasoned that a cell phone user does not share location information with a service provider 
“in any meaningful way.”  Nevertheless, that court held that federal law enforcement 
officers need not demonstrate probable cause – the standard for obtaining a search warrant 
– in order to obtain historical CSLI.  Rather, the officer need only make a showing required 
by the federal Stored Communications Act – that is, “specific and articulable facts showing 
that there are reasonable grounds to believe that [the historical CSLI is] relevant and 
material to an ongoing investigation.”  Id. at 315 (citing 18 U.S.C. §2703(d)); see also In 
re Application of the United States for an Order Authorizing the Release of Historical Cell 
Site Information, 809 F.Supp.2d 113 (E.D.N.Y. 2011) (holding that third party doctrine 
does not apply to historical CSLI). 
32 
 
The Massachusetts Supreme Judicial Court has also rejected the third party doctrine 
with respect to historical CSLI and, construing its state constitutional analog to the Fourth 
Amendment, has looked to the duration of the location tracking to assess whether the cell 
phone user has a reasonable expectation of privacy in historical CSLI.  See Commonwealth 
v. Augustine, 4 N.E.3d 846 (Mass. 2014) (holding that law enforcement access to historical 
CSLI for a two-week period is a search under state constitutional provision, although a 
warrant may not be needed for a period of shorter duration); Commonwealth v. Estabrook, 
38 N.E.3d 231 (Mass. 2015) (confirming that law enforcement officers may obtain 
historical CSLI relating to a period of six hours or less without need for a search warrant).  
c.  Real-Time Location Tracking via Cell Phone 
Real-time tracking of the location of a cell phone – and, presumably the cell phone’s 
owner or user – can occur via data from the cell phone’s GPS, via information about the 
cell towers currently being utilized by the cell phone (i.e., real-time CSLI), and – as in this 
case – via the use of a cell site simulator.  As with historical CSLI, the courts have reached 
different conclusions as to whether such real-time tracking is a search for purposes of the 
Fourth Amendment and the Supreme Court has not yet had occasion to analyze the issue.  
GPS data   
In United States v. Skinner, 690 F.3d 772, 774-76 (6th Cir. 2012), cert. denied, 133 
S.Ct. 2851 (2013), law enforcement officers located the defendant at a roadside truck stop 
33 
 
by tracking, in real time and without a warrant, GPS data broadcast by his cell phone.48  
The Sixth Circuit, noting that the defendant was “traveling on a public road before he 
stopped at a public rest stop,” held that the defendant had no reasonable expectation of 
privacy in the location of his cell phone.  Id. at 778.  Moreover, the tracking took place 
over three days, which the court characterized as the “relatively short-term monitoring” 
that four justices in Jones had believed to be reasonable.  Therefore, in the Sixth Circuit’s 
view, the collection of such data is not a Fourth Amendment search.   
Real-time CSLI   
In Tracey v. State, 152 So.3d 504, 506-07 (Fla. 2014), law enforcement officers 
located the defendant by tracking, in real time and without a warrant, his cell phone’s real-
time CSLI.  The Florida Supreme Court, emphasizing that real-time – and not historical – 
CSLI was at issue, held that a cell phone user has a reasonable expectation of privacy in 
such data, “even on public roads.”  Id. at 516, 526.  Therefore, in that court’s view, the 
collection of that data was a Fourth Amendment search.49  See also In re Application of the 
United States for an Order Authorizing Disclosure of Location Information of a Specified 
Wireless Telephone, 849 F.Supp.2d 526 (D. Md. 2011) (“the subject here has a reasonable 
                                              
48 Law enforcement officers also utilized real-time CSLI, but the defendant 
apparently did not challenge the use of that data on Fourth Amendment grounds.  Skinner, 
690 F.3d at 776-77. 
49 The court also rejected the state’s reliance on the third party doctrine, noting that 
“[s]imply because the cell phone user knows or should know that his cell phone gives off 
signals that enable the service provider to detect its location for call routing purposes ... 
does not mean that the user is consenting to use of that location information by third parties 
for any other unrelated purposes.”  Tracey, 152 So.3d at 522.   
34 
 
expectation of privacy both in his location as revealed by real-time location data [i.e., 
CSLI] and in his movement where his location is subject to continuous tracking over an 
extended period of time, here thirty days”); but see In re Application of the United States 
for an Order for the Disclosure of Telecommunications Records and Authorizing the Use 
of a Pen Register and Trap and Trace Device, 405 F.Supp.2d 435 (S.D.N.Y. 2005) 
(holding, pursuant to the third party doctrine, that the collection of certain real-time CSLI 
is not a Fourth Amendment search). 
Cell Site Simulator   
In United States v. Patrick, 842 F.3d 540, 541 (7th Cir. 2016), law enforcement 
officers located and arrested the defendant – for whom they had a valid arrest warrant – in 
a car on a public street with the assistance of a cell site simulator.  Although the officers 
had obtained a warrant to track the defendant through cell phone data, the application for 
the warrant did not specifically inform the issuing magistrate that a cell site simulator 
would be used.  842 F.3d at 542, 544.  The defendant argued that the warrant was invalid 
and that evidence found on his person at the time of his arrest should be suppressed.  Id. at 
541.  The Seventh Circuit disagreed.  Because the defendant was in a public place at the 
time of the arrest and because “probable cause alone is enough for an arrest in a public 
place,” the court held that the defendant “did not have any privacy interest in his location 
35 
 
at the time” and “[could not] complain about how the police learned his location.”  Id. at 
542, 545.50 
In Patrick, as in this case, the government conceded for purposes of that case that 
use of the cell site simulator was a Fourth Amendment search.  The court’s conclusion that 
the defendant “did not have any privacy interest in his location at the time” seems to imply 
– at least under Katz – that it would not be a search, so long as the defendant was tracked 
in a public place.  In any event, the court demurred on resolving that question in the case 
before it: 
Questions about whether use of a [cell site] simulator is a search, if so 
whether a warrant authorizing this method is essential, and whether in a 
particular situation a [cell site] simulator is a reasonable means of executing 
a warrant, have yet to be addressed by any United States court of appeals.  
We think it best to withhold full analysis until these issues control the 
outcome of a concrete case. 
842 F.3d at 545.  But see United States v. Lambis, 197 F.Supp.3d 606, 611(S.D.N.Y. 2016) 
(use of cell site simulator is search for purposes of Fourth Amendment). 
 
d.  The Andrews Case 
 
As noted above, the Court of Special Appeals has had occasion to consider whether 
law enforcement use of a cell site simulator is a search for purposes of the Fourth 
Amendment in State v. Andrews, 227 Md. App. 350 (2016).  The Andrews decision 
concerned events roughly contemporaneous with those in this case.  The opinion was 
                                              
50 The court noted that the cell site simulator was not used to generate the probable 
cause for the arrest of the defendant, only to find his location.  842 F.3d at 545 (“A fugitive 
cannot be picky about how he is run aground.”). 
36 
 
issued shortly before the Circuit Court’s ruling in this case and was relied upon the Circuit 
Court.   
In Andrews, the defendant had been charged with first-degree murder related to a 
shooting during an illicit drug transaction.  A warrant was issued for his arrest, but police 
were initially unable to locate him.  Officers learned the number of the defendant’s cell 
phone through a confidential informant.  The officers applied for – and obtained – a court 
order based in part on the Pen Register Statute, similar to the order in this case.  Using a 
cell site simulator, officers were able to locate the cell phone – and the defendant – at a 
home in Baltimore.  They arrested the defendant and then obtained a search warrant for the 
home where they found a gun in the cushions of the couch where the defendant had been 
sitting.  The circuit court granted the defendant’s motion to suppress the gun and other 
evidence as fruits of an illegal search – i.e., the use of the cell site simulator without a 
search warrant.51   
The Court of Special Appeals upheld the circuit court’s decision in a comprehensive 
opinion.  After an extensive review of the case law and legal literature, the intermediate 
appellate court concluded that cell phone users have an objectively reasonable expectation 
that the users’ cell phones “will not be used as real-time tracking devices through the direct 
and active interference of law enforcement.”  227 Md. App. at 394-95.  It rejected 
application of the third party doctrine, noting that the particular data intercepted by the cell 
                                              
51 Unlike this case, the circuit court did not conduct a full-fledged hearing on the 
motion to suppress but, with the consent of the parties, held a truncated hearing that 
incorporated testimony from a hearing concerning a discovery dispute. 
37 
 
site simulator had never been transmitted to a service provider.  Id. at 398-99.52  
Consequently, it held that the officers’ use of a cell site simulator to locate the defendant 
was a search for purposes of the Fourth Amendment. 
e.  Summary 
It is evident that, in assessing whether law enforcement use of location tracking data 
and devices is a search for purposes of the Fourth Amendment, courts have looked to a 
variety of factors – whether use of a device involves a physical trespass, whether the device 
is used for long-term or short-term tracking, whether the device tracks movements within 
a private dwelling or on a public street, and whether the information conveyed is also 
knowingly shared with a third party.  In this case, some of those factors – the short duration 
of tracking, its use in this case to identify a building rather than movements within the 
building, and the absence of any physical trespass – favor a conclusion that use of the 
device to find the -4686 phone was not a search.   
On the other hand, as the Court of Special Appeals observed in Andrews, a cell site 
simulator provides law enforcement officers with information not originally collected by 
the service provider and, thus, there is a strong argument that the third party doctrine does 
not apply.  Moreover, depending on the precision of the particular device, it may have the 
capability of providing detailed information about movements within a dwelling.   
                                              
52 In that regard, the court also relied on the panel decision in United States v. 
Graham, 796 F.3d 332, 355-56 (4th Cir. 2015), which rejected the third party doctrine and 
held that law enforcement access to historical CSLI was a search.  Two months after the 
Court of Special Appeals decided Andrews, that decision was overruled by the Fourth 
Circuit sitting en banc.  United States v. Graham, 824 F.3d 421 (2016) (en banc).   
38 
 
 
One of the key cases relied upon in Andrews has since been overruled by the Fourth 
Circuit en banc.53  Moreover, the Supreme Court has now agreed to take up the question 
whether law enforcement access to CSLI implicates the Fourth Amendment54 and thus 
there may be a decision in the near future providing authoritative guidance for that closely-
related issue.  None of this means that the analysis in Andrews is wrong.  Indeed, the 
analysis in Andrews and the other cases summarized above may well prove useful when 
we inevitably must consider the use of a cell site simulator pursuant to the General 
Assembly’s recently-enacted statute.  But, given that the State has conceded for purposes 
of this case that use of the cell site simulator was a search, it seems “best to withhold full 
analysis until these issues control the outcome of a concrete case.”55  
In any event, for purposes of the question whether the detectives in this case acted 
in objectively reasonable good faith, it is enough to note that the holding of the Court of 
Special Appeals post-dated the use of the cell site simulator in this case by two years, and 
the case law in other jurisdictions concerning real-time location tracking did not make it a 
foregone conclusion that use of a cell site simulator would be considered a search in all 
instances under the Fourth Amendment.   
 
                                              
53 See footnote 51. 
54 United States v. Carpenter, ___ U.S.___, 2017 WL 2407484 (June 5, 2017). 
55 Patrick, 842 F.3d at 545; see also City of Ontario, Cal. v. Quon, 560 U.S. 746, 
759 (2010) (“[t]he judiciary risks error by elaborating too fully on the Fourth Amendment 
implications of emerging technology before its role in society has become clear”). 
39 
 
3. 
Court Order as Equivalent to Warrant 
The Fourth Amendment’s prohibition against unreasonable searches is generally 
satisfied when law enforcement officers obtain a warrant authorizing the search in question.  
Riley v. California, 134 S.Ct. 2473, 2482 (2014).56  Here, the State contends that the order 
obtained by the officers based in part on the Pen Register Statute functioned as 
constitutionally-sufficient authorization for the use of the cell site simulator – in other 
words, it was a warrant for purposes of the Fourth Amendment.   
a.  Requirements for a Warrant 
In order to obtain a search warrant, a law enforcement officer must demonstrate 
probable cause in sworn testimony presented to a “neutral and detached magistrate.”  
Illinois v. Gates, 462 U.S. 213, 238-240 (1983).  “Probable cause,” in turn, is “a fair 
probability that contraband or evidence of a crime will be found in a particular place,” id., 
or a showing “that the evidence sought will aid in a particular apprehension or conviction 
for a particular offense,” Dalia v. United States, 441 U.S. 238, 255 (1979).  As for the 
Fourth Amendment’s particularity requirement, although the Supreme Court has not had 
to squarely rule on how it applies to real-time location tracking, the Court suggested that, 
in the context of location tracking by electronic beeper, it would be sufficient for law 
                                              
56 Searches may also be constitutionally “reasonable” if there is an applicable 
exception to the warrant requirement.  Riley, 134 S.Ct. at 2482.  One such exception covers 
searches conducted with the individual’s consent.  Schneckloth v. Bustamonte, 412 U.S. 
218, 219 (1973).  In the Circuit Court, the State claimed that Mr. Copes consented to the 
search of his apartment.  The State, however, did not raise this argument in the Court of 
Special Appeals or this Court.  Therefore, we do not address it. 
40 
 
enforcement officers applying for a warrant to “describe the object into which the beeper 
is to be placed, the circumstances that led agents to wish to install the beeper, and the 
length of time for which beeper surveillance is requested.”57 
b.  Warrants for Location Tracking with Cell Site Simulator 
Two federal district court decisions illustrate the specificity that may be required for 
a warrant authorizing the use of a cell site simulator to locate or track a suspect.  In both 
cases, law enforcement officers obtained a warrant for location tracking and used a cell 
site simulator, and in both cases the defendant later asserted that the use of the cell site 
simulator exceeded the scope of the warrant.  In one case, the officers notified the court 
in the application that they intended to use a “mobile tracking device.”  In the second case, 
the officers did not.  The court denied the motion to suppress in the first case, but granted 
it in the second case. 
In United States v. Ringmaiden, 2013 WL 1932800 (D. Ariz. 2013), law 
enforcement officers obtained a warrant authorizing the “use and monitoring of a mobile 
tracking device” in order to track an “aircard” in the defendant’s computer.  The aircard, 
which allowed the defendant’s computer to wirelessly connect to the internet through a 
service provider’s cell towers, was identified in the warrant by its assigned phone number 
and device serial number.  Id. at *14.  After it was revealed that the officers used a cell 
site simulator to track the aircard, the defendant moved to suppress evidence gathered as 
a result of that tracking.  He argued, among other things, (1) that use of a cell site simulator 
                                              
57 Karo, 468 U.S. at 718. 
41 
 
exceeded the scope of the warrant because it was not specifically authorized by the 
warrant, and (2) that the warrant lacked particularity, because it did not describe the place 
to be searched.   
The federal district court rejected those arguments.  Holding that the use of a cell 
site simulator did not exceed the scope of the warrant, the court first noted that “[t]here is 
no legal requirement that a search warrant specify the precise manner in which the search 
is to be executed.”  Id. at *16.  The court reasoned that the warrant’s reference to a “mobile 
tracking device” reasonably described the equipment used to track signals from the aircard 
– i.e., the cell site simulator.  Id. at *17.  In finding that the warrant was sufficiently 
particular, the court observed that a warrant to locate a particular item need not specify 
the place to be searched, if the warrant provides other information.  Id. at *22.  In the case 
before the court, the particularity requirement was satisfied as the warrant precisely 
identified the aircard to be located by description, telephone number, and device serial 
number.  Id. at *17, 22. 
By contrast, in United States v. Lambis, 197 F.Supp.3d 606 (S.D.N.Y. 2016), 
officers obtained a warrant to track a suspect via CSLI for a target phone.58  The 
application for the warrant made no mention of a “cellular tracking device,” much less a 
cell site simulator.  As in the instant case, the officers first used CSLI to determine the 
                                              
58 It is not clear from the opinion whether the warrant authorized the collection of 
historical or real-time CSLI.  However, the law enforcement officers apparently used the 
CSLI to identify the phone’s location after the warrant was issued, which presumably 
would be real-time CSLI. 
42 
 
phone’s general vicinity and then used a cell site simulator to pinpoint the phone to a 
specific apartment within an apartment building.  The court suppressed the evidence 
discovered in that apartment on the ground that the use of the cell site simulator exceeded 
the scope of the search permitted by the warrant.  The court opined that, because the 
government was able to demonstrate probable cause to obtain a warrant for CSLI, it could 
have also obtained a warrant to use a cell site simulator, if it had wished to do so. 
c.  Orders Based on Pen Register Statute 
As noted earlier, many law enforcement agencies, like the detectives in this case, 
have sought court authorization to use cell site simulators through applications and orders 
based in part on a pen register statute.  Unlike a search warrant, there is no requirement 
that there be a showing of probable cause as a predicate to an order under a pen register 
statute.  However, as in this case, many such applications related to use of cell site 
simulators have purported to make some showing of probable cause. 
Using Real-Time CSLI Pursuant to Order Based on Pen Register Statute 
In United States v. Wilford, 961 F.Supp.2d 740, 744 (D. Md. 2013), law enforcement 
officers obtained an order based in part on the Maryland Pen Register Statute and 
proceeded to “ping”59 the defendant’s cell phone in order to generate real-time CSLI.  The 
                                              
59 As noted above, a cell phone reveals its general geographical location whenever 
it sends or receives a call or text message.  If one “pings” a cell phone – that is, sends 
signals to the phone – the phone may reveal its general geographical location at frequent, 
predictable intervals.  United States v. Wilford, 961 F.Supp.2d 740, 747 (citing Susan 
Friewald, Cell Phone Location Data and the Fourth Amendment: A Question of Law, Not 
Fact, 70 Md. L. Rev. 681, 702-03 (2011)).  In Wilford, law enforcement officers pinged 
the defendant’s phone every 15 minutes.  961 F.Supp.2d at 747. 
43 
 
court assumed that the pinging constituted a Fourth Amendment search and that such 
surveillance was not “embraced” by the Pen Register Statute.  Nevertheless, it held that the 
order satisfied the Fourth Amendment’s warrant requirement.  961 F.Supp.2d at 770-72.  
The court stated that it was immaterial that the order was not titled as a “warrant” and 
looked to the substance of the order and supporting application.   Id. at 773.  The court 
noted that the application was submitted under oath, identified a specific cell phone, and 
“generally provided adequate information obtained through the investigation to establish 
probable cause.”  Id. at 772-73.  
In a case in which the officers provided less detail in an application for an order 
based on a pen register statute, the Florida Supreme Court reached a different result.  
Tracey v. Florida, 152 So.3d 504 (Fl. 2014).  In order to satisfy the relevance standard of 
the pen register statute, the application for the order noted merely that a confidential 
informant told law enforcement that the defendant (1) transports drugs from one location 
to another and (2) uses a certain cell phone number.  The application did not seek authority 
to track the location of the defendant’s cell phone, nor did it seek access to real-time CSLI.  
Nevertheless, the officers used real-time CSLI to track the defendant inside a private home.  
The court held that the information provided in the application did not amount to probable 
cause and that the order, therefore, did not provide constitutionally-sufficient authorization 
for the location tracking.  See also In re Application of the United States for an Order 
Authorizing (1) Installation and Use of a Pen Register and Trap and Trace Device or 
Process, (2) Access to Customer Records, and (3) Cell Phone Tracking, 441 F.Supp.2d 816 
44 
 
(S.D. Texas 2006) (denying application for order submitted under 18 U.S.C. §3121 that 
sought authorization for the collection of CSLI). 
Using Cell Site Simulator Pursuant to Order Based on Pen Register Statute  
In a case with facts very similar to this case, the Wisconsin Supreme Court assumed 
that law enforcement use of a cell site simulator is a search for purposes of the Fourth 
Amendment and that a warrant would be required because use of the cell site simulator led 
to the defendant’s apprehension in a private dwelling.  That court concluded that an order 
based on the state pen register statute sufficed as a warrant in light of the content of the 
application for that order and the order itself.  Wisconsin v. Tate, 849 N.W.2d 798 (Wis. 
2014), cert. denied, 135 S.Ct. 1166 (2015).   
In Tate, officers were investigating a murder that occurred outside a grocery store.  
Surveillance camera footage from the store showed the murderer purchasing a prepaid cell 
phone from the store shortly before committing the crime.  The police obtained identifying 
information about the phone, and obtained an order based on the Wisconsin pen register 
statute, which is similar in pertinent respects to the Maryland statute.  The application for 
the order summarized the facts of the investigation and the purpose in tracking the cell 
phone.  The order authorized the officers to obtain not only information provided by a pen 
register, but also CSLI from the service provider, as well as GPS location information and 
“the identification of the physical location of a target cellular phone.”  849 N.W.2d at 802 
n.6.  As in this case, the officers then used a cell site simulator in combination with CSLI 
in order to locate the phone within a specific apartment building.  Id. at 804.  The officers 
45 
 
canvassed the apartments in the building, eventually finding the individual from the 
grocery store video in one of the apartments.  Id. 
In holding that the trial court properly denied the defendant’s motion to suppress 
evidence and statements, the Wisconsin Supreme Court held that the order functioned as a 
warrant for purposes of the Fourth Amendment and that the officers’ use of the cell site 
simulator was not an unreasonable search.  Id. at 801 & n.3.  The court noted that the 
application for the order described sufficient facts to support a finding of probable cause, 
even though the Wisconsin statute, like the Maryland Pen Register Statute, required only a 
showing that the information sought would be relevant to an ongoing criminal 
investigation.  In addition, it held that the order was sufficiently particular because it 
identified a particular phone and “permit[ted] a particularized collection of cell site 
information for only [that] phone.”  Id. at 810. 
 
As noted above, in Andrews, the police obtained an order – similar to the order in 
this case – under the Maryland Pen Register Statute.  The Court of Special Appeals 
concluded that the order did not suffice as a warrant in that case.  The court compared the 
functionality of a pen register and trap and trace device to the functionality of a cell site 
simulator.  It also looked to federal court decisions holding that the government was not 
entitled to obtain real-time CSLI under the federal pen register statute without a showing 
of probable cause60 and a federal court decision declining to issue such an order with 
                                              
60 In re Application of the United States for an Order Authorizing Installation & 
Use of a Pen Register, 415 F.Supp.2d 211 (W.D.N.Y. 2006); In re Application for Pen 
46 
 
respect to a cell site simulator.61  The court also noted that, unlike the standards for a search 
warrant, the Pen Register Statute does not require a showing of probable cause, nor does it 
contain a particularity requirement.62  The intermediate appellate court concluded that the 
Pen Register Statute was limited in its reach and not intended to apply to “other, newer 
technologies.”  227 Md. App. at 406.  Finally, the court stated that the order was not “based 
on sufficient information about the technology to allow [the issuing] court to contour 
reasonable limitations on the scope and manner of the search” and did not “provide[] 
adequate protections in case any third-party cell phone information might be 
unintentionally intercepted.”  Id. at 413.63 
 
                                              
Register &Trap/Trace Device with Cell Location Auth., 396 F.Supp.2d 747 (S.D. Tex. 
2005). 
61 In the Matter of the Application of the United States for an Order Authorizing the 
Installation and Use of Pen Register and Trap and Trace Device, 890 F.Supp.2d 747 (S.D. 
Tex. 2012). 
62 The court contrasted the showing required under the Pen Register Statute with the 
stricter showing required under the statute that now governs real-time location tracking 
through cell phones.  227 Md. App. at 406-7.  That statute is described briefly in Part I.A.3 
of this opinion above. 
63 The court related the perceived lack of detail to a nondisclosure agreement 
between the FBI and the State’s Attorney’s Office concerning cell site simulators.  The 
nondisclosure agreement stated that use of the equipment “shall be protected from potential 
compromise by precluding disclosure of this information to the public in any manner 
including ... during judicial hearings.”  227 Md. App. at 374.  It also stated that the Police 
Department “shall not, in any civil or criminal proceeding, use or provide any information 
concerning the [equipment] ... during pre-trial matters, in search warrants and related 
affidavits ... without the prior written approval of the FBI.”  Id. at 374-75.  In the view of 
the Court of Special Appeals, the agreement rendered the application for the order 
misleading and the resulting order “overreaching.”  
47 
 
d.  Summary 
There is significant support in the case law for the position that an order under a pen 
register statute that is modified appropriately may function as a warrant for purposes of the 
Fourth Amendment.  This is true when, in addition to being sworn, the application for the 
order demonstrates probable cause, and the order satisfies the particularity requirement of 
the Fourth Amendment.  When these criteria are met, it does not matter whether the order 
is labeled a “warrant.”  The constitutional requirements are addressed to substance, not 
form. 
In this case, the detectives submitted to the court a sworn application64 based on the 
Pen Register Statute that purported to provide probable cause by summarizing evidence 
they had developed concerning the crime under investigation.  In particular, the application 
identified a particular cell phone by number that was linked to the victim of the crime, but 
not found with her body.  The application detailed the basis for the belief that location of 
the cell phone would lead to apprehension of the murderer.  It requested authorization for 
“interception of real-time cell site information.”  The resulting order was issued by a 
“neutral magistrate” (a circuit court judge), stated that “the Court finds that probable cause 
                                              
64 Mr. Copes has suggested that the order was not a sworn document because the 
detective submitting the application refers to himself as “your applicant” and the 
application at various place indicates that he “states” or “offers” information.  This ignores 
the fact that the detective also uses the verb “certify” and the signature page indicates that 
the application was “sworn,” although the date is missing.  Moreover, there is no question 
that the application and order are based on the requirements of the Pen Register Statute 
which provides for applications under oath or affirmation.  Mr. Copes has not provided 
sufficient evidence to defeat the “presumption of regularity” that normally attaches to court 
proceedings.  Black v. State, 426 Md. 328, 337 (2012).   
48 
 
exists,” identified a specific cell phone to be tracked, and authorized the actions requested 
in the application. 
Nevertheless, we need not decide whether the order did, in the end, provide 
constitutionally-sufficient authorization for law enforcement use of the cell site simulator 
in this case.  We recognize the strength the State’s argument on this issue, however, because 
it is relevant to the analysis whether it is appropriate to apply the good faith exception to 
the exclusionary rule in this case. 
4. 
Whether the Good Faith Exception Applies 
 
In our view, the detectives investigating the murder of Ms. Jenkins were engaged in 
“objectively reasonable law enforcement activity” when they used the cell site simulator 
pursuant to the order based on the Pen Register Statute.  According to Detective Kershaw, 
applications for similar orders had been approved “many, many times,” and never denied.  
On their face, the application and order likely satisfy the requirements for a warrant that 
complies with the Fourth Amendment. There is a strong – perhaps even conclusive – 
argument that the order obtained under the Pen Register Statute provided constitutionally-
sufficient authorization for use of the cell site simulator.  Both Detective Haley and 
Detective Kershaw testified that they believed that the order authorized them to use the cell 
site simulator.   
The Circuit Court reiterated twice that it believed that the detectives investigating 
Ms. Jenkins’ murder were “operat[ing] in good faith” when they used the cell site simulator 
pursuant to a court order in order to locate the suspect.  Indeed, at the conclusion of the 
motions hearing, the court complimented Detective Kershaw on his “fine work” in the case.  
49 
 
Yet in suppressing the evidence obtained in that investigation, the court appeared to 
believe, without articulating it, that the use of the cell site simulator foreclosed any 
application of the good faith exception.  
 
In its opinion in this case, the Court of Special Appeals did explicitly address the 
good faith exception and concluded that it did not apply, reasoning that application for the 
order “did not provide clearly what technology it sought to use, nor the manner in which 
the technology operated.”  In doing so, the court referred not to the record of this case, but 
to a passage in Andrews concerning the nondisclosure agreement between the FBI and the 
State’s Attorney’s Office.  To the extent that the Andrews decision is interpreted as a 
categorical denial of a good faith exception when police used a cell site simulator pursuant 
to a court order based on the Pen Register Statute, we reject such an interpretation.65   
 
None of the reasons identified by the Supreme Court or this Court for discounting 
law enforcement reliance on an apparently valid warrant apply here.  There is no allegation 
that the issuing judge “abandon[ed] a detached and neutral role” or that the detectives 
provided knowingly false information.  Nor can it be said that probable cause was so 
lacking as “to render official belief in its existence entirely unreasonable” or that it was 
                                              
65 The Andrews decision did not explicitly consider whether the good faith exception 
applied to the use of the cell site simulator in the case before it.  It did consider whether the 
State could rely on the good faith exception to save from suppression the evidence that was 
recovered pursuant to a search warrant following use of the cell site simulator.  It concluded 
that the search warrant was tainted by the illegal search conducted with the cell site 
simulator.  227 Md. App. at 417-21. 
50 
 
“facially deficient” with respect to the particularity requirement.66  See Leon, 468 U.S. at 
923. 
The alleged defect in the application and order is not that they failed to apprise the 
issuing judge that a cellular tracking device would be used to do real-time tracking that 
involved initiating a signal, but that they failed to go into greater detail about that 
technology.67  However, search warrants need not “include a specification of the precise 
                                              
66 See United States v. Karo, 468 U.S. at 718 (warrant for location tracking will 
likely satisfy the Fourth Amendment’s particularity requirement if law enforcement 
“describe the object into which the beeper is to be placed, the circumstances that led agents 
to wish to install the beeper, and the length of time for which beeper surveillance is 
requested”); see also State v. Tate, 849 N.W.2d at 810 (particularity requirement was met 
when an order identified the tracked cell phone by its assigned phone number); see also 
United States v. Ringmaiden, 2013 WL 1932800 at *17 (D. Ariz. 2013) (particularity 
requirement was met when a warrant identified the aircard to be tracked by description, 
telephone number, and device serial number). 
 
67 The Dissenting Opinion argues that the good faith exception cannot be applied in 
this case because the order was “facially deficient” as a search warrant in that it was “silent” 
regarding the details of how a cell site simulator works.  Dissenting Opinion at 11.  
However, statutes that implement the requirements of the Fourth Amendment for searches 
arguably more intrusive than one undertaken with a cell site simulator do not require an 
officer explain in detail the technical specifications of a particular device used to carry out 
a proposed search.  For example, the statutes governing the authorization of a wiretap – 
essentially, a search warrant that allows for the interception of private communications in 
real time – do not require such detail.  See CJ §10-401 et seq. (Maryland wiretap statute); 
18 U.S.C. §2510 et seq. (federal wiretap statute).  (As the excerpts from the Maryland 
Wiretap Statute quoted in the Dissenting Opinion illustrate, those statutes do not specify 
the technology used to effect a wiretap other than to refer to it as an “electronic, mechanical 
or other device.”  Dissenting Opinion at 13-20).  Rather, an application for a wiretap under 
those statutes describes the probable cause supporting the issuance of the order, the crimes 
under investigation, the period of the proposed interception, the type of communications 
sought to be intercepted, the persons likely to be involved in those communications, the 
efforts to minimize the interception of non-pertinent communications, and related matters.  
See ABA Standards for Criminal Justice – Electronic Surveillance (3d ed. 2001) at 91-166 
(detailing standards for wiretap application and order); United States Attorneys’ Manual, 
Criminal Resource Manual, Chapters 28 (Electronic Surveillance – Title III Applications), 
51 
 
manner in which they are to be executed.”  Dalia, 441 U.S. at 257.  It is true that the 
application and the related order suffer from vices endemic to many legal documents – 
grammatically-challenged prose, repetitive phrasing, multi-paragraph sentences, numerous 
subordinate clauses, parades of synonyms, legions of commas interspersed with semi-
colons.  Yet the application and order clearly inform a reasonably diligent reader of what 
the officers seek to do and how they plan to do it (even if they do not describe the technical 
details). 
The application states that the detectives wished to use, in addition to the pen 
register and trap and trace device, a “Cellular Tracking Device” and “Real Time Tracking 
Tool”; among other things, that they would employ “surreptitious or duplication of 
facilities” and “initiate a signal to determine the location of the subject’s mobile phone”; 
and that they will be engaged in “real time tracking” of a particular cell phone identified 
by number.  A fair reading of this order would encompass a cell site simulator.  Certainly, 
there could have been more detail.  Undoubtedly, the application could have been clearer.  
But that hardly means that the order is “facially invalid” as clearly lacking particularity. 
With respect to the nondisclosure agreement discussed in Andrews, the testimony at 
the hearing in this case was that the detectives would have answered any questions of the 
                                              
https://www.justice.gov/usam/criminal-resource-manual-28-electronic-surveillance-title-
iii-applications [https://perma.cc/6EDW-MPYD], 92 (Title III Procedures – Attachment C 
– 
Title 
III 
Wire 
Affidavit 
Checklist 
for 
Law 
Enforcement 
Agents), 
https://www.justice.gov/usam/criminal-resource-manual-92-title-iii-procedures-
attachment-c [https://perma.cc/P2ZU-Q84X].  Nor do law enforcement officers typically 
go beyond the requirements of those statutes to detail the particular technology utilized to 
effect a wiretap when applying for one.  Id.  Indeed, the Supreme Court has explicitly held 
that there is no requirement that they do so.  Dalia, 441 U.S. at 257. 
52 
 
issuing judge about what they planned to do.  Even if we ignore that testimony, Dalia 
rejects any requirement that law enforcement officials spell out, in precise detail, their 
intended method of surveillance when applying for a warrant.  This does not mean that the 
authorizing judge was required to sign the order if the detectives had declined to answer 
questions about the details.68  But it does mean that the absence of greater detail does not 
render the order that was issued so fatally deficient that the detectives could not execute it 
in good faith. 
III 
Conclusion 
 
For the reasons explained above, we hold that, based on existing case law, it was 
objectively reasonable for the detectives to believe that their use of the cell site simulator 
pursuant to the court order was permissible under the Fourth Amendment.  Given that the 
Supreme Court has instructed that suppression should be a “last result” and not a “first 
impulse,” this is an appropriate case for application of the good faith exception.  We hold, 
therefore, that evidence obtained as a result of detectives’ use of the cell site simulator 
should not be suppressed because of use of that device. 
 
JUDGMENT OF THE COURT OF SPECIAL 
APPEALS REVERSED.  COSTS TO BE PAID BY 
RESPONDENT. 
                                              
68 The judge to whom an application is presented can certainly ask for technical 
information, if the judge believes that it will be helpful to the decision whether to approve 
the warrant.  If the judge does so, the officers may not mislead the judge.  But, in the 
absence of such a request, the failure to provide technical details in an application is not 
fatal to a warrant. 
Circuit Court for Baltimore City 
Case No. 11409005 
Argued: April 3, 2017 
 
IN THE COURT OF APPEALS 
 
OF MARYLAND 
 
No. 84 
 
September Term, 2016 
 
__________________________________ 
 
STATE OF MARYLAND 
v. 
ROBERT L. COPES, JR. 
__________________________________ 
 
Barbera, C.J., 
Greene, 
Adkins, 
McDonald, 
Watts, 
Hotten, 
Getty, 
 
JJ. 
__________________________________ 
 
Dissenting opinion by Hotten, J., which 
Greene and Adkins, JJ., join. 
__________________________________ 
 
Filed:  July 28, 2017
 
 
 
 
 
 
 
 
 
 
Respectfully, I dissent from the majority opinion in this case.  I agree with my 
brethren on the Court of Special Appeals that “… the use of a cell site simulator requires a 
valid search warrant, or an order satisfying the constitutional requirements of a warrant, 
unless an established exception to the warrant requirement applies[,]” and that the use of a 
pen register/trap and trace order to use a cell site simulator in this case was insufficient to 
satisfy that threshold.  State v. Andrews, 227 Md. App. 350, 355, 134 A.3d 324, 327 (2016).   
 
For an issuing judge to appreciate the gravity of the exercise of the requirements 
and parameters of the Fourth Amendment and any intrusion on a person’s privacy rights, 
the issuing judge must appreciate the scope and manner of the search proposed to be 
conducted. The more an issuing judge understands the technology associated with the 
device sought to be used, the better the issuing judge can appreciate the constitutional 
impact of the search request, particularly when the device has the capacity to conduct a 
very broad, intrusive search impacting the Fourth Amendment.  As the Court of Special 
Appeals eloquently stated, “[t]he analytical framework requires analysis of the 
functionality of the surveillance device and the range of information potentially revealed 
by its use.”  Andrews, 227 Md. App. at 376, 134 A.3d at 338.   
I. 
The Order In this Case Was Not A Search Warrant Within the Dictates 
of the Fourth Amendment 
 
In the case at bar, the Baltimore City Police Department (“BCPD”) relied on Courts 
& Judicial Proceedings Article (“Cts. & Jud. Proc.”) §10-4B-03 as its basis for seeking an 
order to use the Hailstorm device to locate a cell phone that was associated with the victim, 
Ina Jenkins.  Cts. & Jud. Proc. §10-4B-03 states: 
 
2 
 
Application or extension of order by investigative or law enforcement 
officers 
 
(a) An investigative or law enforcement officer may make application for an 
order or an extension of an order under §10-4B-04 of this subtitle or 
approving the installation and use of a pen register or a trap and trace 
device, in writing, under oath or equivalent affirmation, to a court of 
competent jurisdiction of this State. 
 
Contents of application 
 
(b) An application under subsection (a) of this section shall include: 
(1) The identity of the State law enforcement or investigative officer 
making the application and the identity of the law enforcement agency 
conducting the investigation; and 
(2) A statement under oath by the applicant that the information likely to 
be obtained is relevant to an ongoing criminal investigation being 
conducted by that agency. 
 
Cts. & Jud. Proc. §10-4B-01 defines “pen register” and “trap and trace” as follows: 
 
(c) (1) “Pen register” means a device or process that records and decodes  
dialing, routing, addressing or signaling information transmitted by an 
instrument or facility from which a wire or electronic communication 
is transmitted. 
 
* 
* 
* 
(d) (1) “Trap and trace device” means a device or process that captures the 
incoming electronic or other impulses that identify the originating 
number or other dialing, routing, addressing, and signaling 
information reasonably likely to identify the source of a wire or 
electronic communication. 
 
* 
* 
* 
 
 
The cell site simulator (hereinafter “Hailstorm device”) used by the BCPD in this 
case differs from both a pen register and trap & trace because it actively seeks out and 
provides real time location, and other information, regarding a cell phone and, presumably, 
the person using it.   
 
3 
 
Detective John Haley (“Det. Haley”), a member of BCPD’s Advanced Technical 
Team, asserted at the suppression hearing that the Hailstorm device “acts like a cell 
tower[,]” but then explained that when a police officer inputs the unique electronic serial 
number (“ESN”) associated with a specific cell phone into the Hailstorm device, the device 
then actively seeks out the location of that cell phone – unlike a cell phone tower, which 
passively awaits connection to a cell phone.  Det. Haley also explained that once the 
Hailstorm device locates the target cell phone, “the phone thinks that the Hailstorm is the 
tower, the cell site. So the phone is going to connect with the Hailstorm.”  Upon connecting 
to the Hailstorm device, the target cell phone cannot be used, except to call 9-1-1, until the 
cell phone is disconnected from the Hailstorm device. Det. Haley also noted that the 
Hailstorm device cannot connect to the target cell phone if the cell phone is in use because 
the phone is already connected to one or more of the service provider’s towers.     
Det. Haley acknowledged that, in addition to locating the target cell phone, the 
Hailstorm device also collects the cell phone information for each cell phone that is located 
within a two-block radius of the device and is located on the same channel1 that the 
Hailstorm device is using.2  Det. Haley also acknowledged that the Hailstorm device sends 
                                              
1 Det. Haley explained that Verizon, the service provider in this case, has about ten 
channels and that cell phones in a given area will seek out the strongest channel to transmit 
signals.  Det. Haley also explained that the Hailstorm device works the same way, it surveys 
the area where it is activated to determine the strongest channel to transmit, and utilizes 
that channel to locate the target cell phone. Det. Haley acknowledged that the Hailstorm 
device can collect the information of anywhere between dozens to hundreds of cell phones 
that are not the target phone the Hailstorm device is searching for.  
 
2 Det. Haley testified that at the end of each night the police delete all the cell phone 
information that was stored on the Hailstorm device from its use during the day. 
 
4 
 
a signal that “goes inside” private homes in search of the target cell phone, and that the 
police did not obtain a separate warrant for 4014 Penhurst Avenue – where the target cell 
phone in this case was ultimately located.  Thus, the Hailstorm device collects far more 
information than what is authorized by the statutory scope of the Maryland Pen Register 
statute. 
Although the Majority does not hinge its analysis on the question of whether the 
Pen Register/Trap & Trace and Cellular Tracking Device order relied on in this case was 
constitutionally sufficient – it assumes that the order was inadequate for the purposes of 
the opinion – the Majority, nonetheless recognizes the strength of the State’s argument 
regarding that issue.  See Maj. Slip Op. at 48.  The Majority notes that in Wisconsin v. Tate, 
849 N.W.2d 798 (Wis. 2014), cert. denied, 135 S. Ct. 1166 (2015), the Wisconsin Supreme 
Court considered a case similar to the case at bar, which concluded that an order based on 
the state’s pen register statute was sufficient to constitute a warrant in light of the content 
of the application and the order itself. See id. at 810.  Central to the Tate Court’s holding 
was its determination that the Wisconsin pen register statute only required a showing that 
the information sought would be relevant to an ongoing criminal investigation, and the 
Court determined that the order was sufficiently particular because it identified a particular 
phone and “permit[ted] a particularized collection of cell site information for only [that] 
phone.” Id.  
Significantly, both the Tate Court and the Majority do not acknowledge that cell site 
simulators not only “search” for the target cell phone, but also “search” the surrounding 
area through the emission of a signal.  In the present case, the Hailstorm device, which 
 
5 
 
technologically presents significant surveillance capabilities, not only searched for the 
target cell phone, but also searched all of the residences in the two block radius of the 
device, including Respondent’s residence at 4014 Penhurst Avenue.  This type of search is 
similar, factually, to the circumstances in Kyllo v. United States, 533 U.S. 27, 121 S. Ct. 
2038 (2001), where the United States Supreme Court held that the use of thermal energy 
technology constituted a search for the purposes of the Fourth Amendment, when the police 
used the technology to detect heat emissions from the defendant’s home.  Id. at 34, 121 S. 
Ct. at 2043.  The Supreme Court concluded in Kyllo that “[w]here … the Government uses 
a device that is not in general public use, to explore the details of the home that would 
previously have been unknowable without physical intrusion, the surveillance is a ‘search’ 
and is presumptively unreasonable without a warrant.”  Id. at 40, 121 S. Ct. at 2046.  Here, 
the police utilized the Hailstorm device – technology that was not available to the public – 
to actively seek out the location of a cell phone through the emission of a signal that 
“explore[d] the details” of the residences within a two-block radius of the Hailstorm device 
“that would have previously been unknowable without” the intrusion of the signal.  See id. 
The State concedes for the purposes of this case that the use of the Hailstorm device 
to locate the target phone constituted a “search” within the meaning of the Fourth 
Amendment, but argues that the Pen Register/Trap & Trace and Cellular Tracking Device 
order was constitutionally sufficient to authorize the use of the Hailstorm device to search 
 
6 
 
for the target cell phone, i.e. the equivalent of obtaining a search warrant.  The pen register 
order in this case stated that, pursuant to Cts. & Jud. Proc. §10-4B-04: 3 
                                              
3 Cts. & Jud. Proc. §10-4B-04 states, in relevant part: 
 
 
 
 
 
 
 
 
 
Information obtained relevant to criminal investigations 
 
(a) (1) Upon application made under §10-4B-03 of this subtitle, the court 
shall enter an ex parte order authorizing the installation and use of a pen 
register or a trap and trace device within the jurisdiction of the court if 
the court finds that information likely to be obtained by the installation 
and use is relevant to an ongoing criminal investigation. 
* 
* 
* 
Contents of order 
 
(b) An order issued under this section shall: 
(1) Specify the identity, if known, of the person to whom is leased or in 
whose name is listed the telephone line or other facility to which the 
pen register or trap and trace device is to be attached or applied; 
(2) Specify the identity, if known, of the person who is the subject of the 
criminal investigation;  
(3) Specify the attributes of the communications to which the order 
applies, including the number or other identifier and, if known, the 
location of the telephone line or other facility to which the pen register 
or trap and trace device is to be attached or applied, and, in the case 
of a trap and trace device, the geographic limits of the trap and trace 
order; 
(4) Contain a description of the offense to which the information likely to 
be obtained by the pen register or trap and trace device relates; and 
(5) Direct, upon the request of the applicant, the furnishing of 
information, facilities, and technical assistance necessary to 
accomplish the installation of the pen register or trap and trace device 
under §10-4B-05 of this subtitle. 
 
Duration of order 
 
(c) (1) An order issued under this section shall authorize the installation and 
use of a pen register or a trap and trace device for a period not to exceed 
60 days. 
* 
* 
* 
 
7 
 
that as part of a criminal investigation of Unknown Person or Persons and 
others as yet unknown, the Baltimore Police Department (BPD), Drug 
Enforcement Agency (DEA), Federal Bureau of Investigation (FBI), United 
States Marshals Service (USMS), United States Secret Service (USSS), 
Immigration Customs Enforcement (ICE), Alcohol Tobacco and Firearms 
(ATF), Sytech, or any other designated law enforcement agency (hereinafter 
referred to as “Agencies”) are authorized to use for a period of sixty (60) 
days from the date of installation, a Pen Register \ Trap & Trace and Cellular 
Tracking Device to include cell site information, call detail, without 
geographical limits, which shall be installed and used within the jurisdiction 
of this Court, upon the telephone having the number(s): [XXX-XX] -4686, a 
AT&T Sprint/Nextel; Virgin Mobile; T-Mobile; Cellco Partnership, DBA 
Verizon Wireless, Verizon; Cricket Communications, Inc; and / or any other 
Telecommunication service provider, telephone; and it is further 
 
ORDERED, that the Agencies shall complete the necessary installation of 
the Pen Register \ Trap & Trace and Cellular Tracking Device … to employ 
surreptitious or duplication of facilities, technical devices or equipment to 
accomplish the installation and use of a Pen Register \ Trap & Trace and 
Cellular Tracking Device, unobtrusively and with a minimum interference to 
the service of the subscriber(s) of the aforesaid telephone, and shall initiate a 
signal to determine the location of the subject’s mobile device on the service 
provider’s network or with such other reference points as may be reasonably 
available, Global Position System Tracing and Tracking, Mobile Locator 
tools, R.T.T. (Real Time Tracking Tool), Precision Locations and any and all 
locations, and such provider shall initiate a signal to determine the location of 
the subject’s mobile device on the service provider’s network or with such 
other reference points as may be reasonably available and at such intervals 
and times as directed by the law enforcement agent / agencies serving this 
order[.] 
* 
* 
* 
The Majority notes that the order authorizes the BCPD to use a “Cellular Tracking Device” 
and “Real Time Tracking Tool” to, among other things, employ “surreptitious or 
duplication of facilities” and “initiate a signal to determine the location of the subject’s 
mobile phone” and that they will be engaged in “real time tracking” of the specific cell 
phone identified by number. See Maj. Slip Op. at 51.  The Majority does not take into 
account that the terms “Cellular Tracking Device” and “Real Time Tracking Tool” are 
 
8 
 
neither referenced nor defined in the Maryland Pen Register Statute, and that neither the 
application nor the order in this case provide definitions for those terms.  In fact, the pen 
register application submitted in this case, and the resulting order, omitted any description 
of the Hailstorm device.  Additionally, the description of the activity that the order 
authorizes, specifically the authority to “initiate a signal” does not adequately describe how 
the Hailstorm device works.  As noted, supra, the Hailstorm device not only emits a signal 
to locate the target phone, but it also forcibly connects the target cell phone to the device, 
rendering the phone inoperable by the user for the duration that the phone is connected to 
the Hailstorm device.   
Even ignoring the fact that the order relied on a statute that did not authorize the 
type of technology that was used, the order also did not comply with the particularity 
requirement because it failed to adequately describe “the place to be searched[.]”  See 
United States v. Grubbs, 547 U.S. 90, 97, 126 S. Ct. 1494, 1500 (2006).  While the order 
did identify the specific cell phone that would be targeted by the Hailstorm device, the 
order also also authorized the BCPD to use the “Pen Register \ Trap & Trace and Cellular 
Tracking device to include cell site information, call detail, without geographic limits,” 
thereby, failing to adequately describe “the place to be searched” i.e. the Penhurst 
neighborhood where the search was ultimately conducted.  The breadth of the language in 
the order allows the BCPD to activate the Hailstorm device in an area, for up to 60 days, 
with the potential of intruding on the privacy of thousands of individuals’ privacy in search 
of the target cellphone.  Such an order cannot suffice as a warrant that satisfies the dictates 
of the Fourth Amendment because the Fourth Amendment prohibits general warrants.  See 
 
9 
 
Andresen v. Maryland, 427 U.S. 463, 480, 96 S. Ct. 2737, 2748 (1976) (“General warrants, 
of course, are prohibited by the Fourth Amendment … ‘[T]he problem [posed by the 
general warrant] is not that of intrusion Per se, but of a general, exploratory rummaging in 
a person’s belongings …. (The Fourth Amendment addresses this problem) by requiring a 
‘particular description’ of the things to be seized.’”) (quoting Coolidge v. New Hampshire, 
403 U.S. 443, 467, 91 S. Ct. 2022, 2038 (1971)) (alterations in original). Accordingly, to 
the extent the Majority found the State’s argument persuasive that the pen register order in 
this case was constitutionally sufficient, I respectfully disagree.  See Maj. Slip Op. at 48. 
II. 
The Good Faith Exception to the Exclusionary Rule Cannot Apply 
I also disagree with the Majority’s conclusion that the police officers in this case 
were engaged in “objectively reasonable law enforcement activity” when they used the 
Hailstorm device in reliance on the language contained in the Pen Register/Trap & Trace 
and Cellular Tracking Device order.  The Majority found persuasive Detective Brian 
Kershaw’s (“Det. Kershaw”) testimony that applications for similar orders had been 
approved “many, many times” and were never denied.  See Maj. Slip Op. at 48.  The 
Majority acknowledged that the BCPD was subject to a nondisclosure agreement regarding 
the Hailstorm technology,4 but determined that “the testimony at the hearing in this case 
was that the detectives would have answered any questions of the issuing judge about what 
                                              
4 See Andrews, 227 Md. App. at 374-77, 134 A.3d at 337-339 (discussing the terms 
of the nondisclosure agreement entered into between the State’s Attorney for Baltimore 
City and the Federal Bureau of Investigation as a condition of the Baltimore City Police 
Department’s use of “certain ‘wireless collection equipment/technology manufactured by 
[the] Harris [Corporation].’”). 
 
10 
 
they planned to do.” Maj. Slip Op. at 51-52 (emphasis in original).  While it is true that 
Det. Haley testified that he would have answered any questions that the issuing judge may 
have had regarding the modified language in the application and order, I find it 
disingenuous for Det. Haley to state in 2016 that he would have been forthcoming about 
the Hailstorm technology at the time the order was issued in February 2014, in light of the 
nondisclosure agreement, which he acknowledged required Baltimore City police officers 
“to basically not talk about the – not talk about the Hailstorm.”   
The Supreme Court has held that there are four circumstances where the good faith 
exception to the exclusionary rule does not apply, and suppression remains the appropriate 
remedy if: (1) the magistrate or judge issuing a warrant was misled by information in an 
affidavit that the affiant knew was false or would have known was false except for his or 
her reckless disregard of the truth; (2) the issuing magistrate has wholly abandoned his or 
her judicial role; (3) the warrant is based on an affidavit so lacking in indicia of probable 
cause as to render official belief in its existence entirely unreasonable; and (4) the warrant 
is so facially deficient – i.e. failing to particularize the place to be searched or the things to 
be seized – that the executing officers cannot reasonably presume it to be valid.  See United 
States v. Leon, 468 U.S. 897, 923, 104 S. Ct. 3405, 3421 (1984) (citations omitted).  The 
Majority concluded that none of the four reasons identified by the Leon Court applied in 
the present case. I disagree.  I find that the fourth circumstance is applicable in this case 
because it was unreasonable for the police officers to presume that the Pen Register/Trap 
& Trace and Cellular Tracking Device order was sufficient to authorize their use of the 
Hailstorm device. As discussed, supra, the Pen Register/Trap & Trace and Cellular 
 
11 
 
Tracking Device Order is not a search warrant pursuant to the Fourth Amendment because 
it was neither represented as a warrant when presented to the issuing judge nor did it 
comport with the dictates of the Fourth Amendment requiring that a warrant particularly 
describe the place to be search or the technology to be used in conducting the search.  
Accordingly, for the Pen Register/Trap & Trace and Cellular Tracking Device to be facially 
sufficient to authorize the use of the Hailstorm device it was required to specify the place 
to be searched, i.e. the area where the police officers intended to employ the Hailstorm 
device.  The order does not reference a specific area the police intended to employ the 
Hailstorm device, it only referenced the cell phone number that was subject to the order.   
The order also failed to adequately describe the type of technology that the police 
officers intended to use in this case.  The Majority asserts that the alleged defect in the 
application and order is not that they failed to apprise the issuing judge that a cellular 
tracking device would be used to do real-time tracking that involved initiating a signal, but 
that they failed to go into greater detail about that technology.  See Maj. Slip Op. at 50. The 
Majority then concludes that “the application and order clearly inform a reasonably diligent 
reader of what the officers seek to do and how they plan to do it (even if they do not describe 
the details).” Id.  I disagree.  I find that the application and order are silent regarding the 
Hailstorm technology and how it functions.  As noted, supra, the Hailstorm device does 
not just “initiate a signal” to track a cell phone, it forces the target cell phone to connect to 
the device, rendering the target cell phone inoperable for the duration that it is connected 
to the Hailstorm device.  The Hailstorm device also collects the cell phone information of 
all surrounding cell phones that are located within a two-block radius of the Hailstorm 
 
12 
 
device and use the same channel that the Hailstorm device utilizes to emit its signal.  
Nothing in the language of the application or order in this case suggests that the police 
intended to use this type of invasive technology.   
The Majority observes in a footnote that “statutes that implement the requirements 
of the Fourth Amendment for searches arguably more intrusive than one undertaken with 
a cell site simulator do not require an officer [to] explain in detail the technical 
specifications of a particular device used to carry out a proposed search.”  Maj. Slip Op. at 
50 n. 67.  As an example, the Majority notes that “the statutes governing the authorization 
of a wiretap – essentially, a search warrant that allows for the interception of private 
communications in real time – do not require such [technical] detail.”  Id. (citing Cts. & 
Jud. Proc. §10-401, et seq.; 18 U.S.C. §2510, et seq.).  The Majority summarizes the 
requirements necessary for an application to obtain a wiretap pursuant to the above-
referenced statutes, and concludes that police officers neither “go beyond the requirements 
of those statutes to detail the particular technology utilized to effect a wiretap when 
applying for one[,]” nor are required to do so, pursuant to the U.S. Supreme Court decision 
in Dalia v. United States, 441 U.S. 238, 99 S. Ct. 1682 (1979), which explicitly held there 
was no requirement that they do so. See id. (citing Dalia, 441 U.S. at 257, 99 S. Ct. at 
1693). 
 
In relying on the wiretapping statutes in support of its view, the Majority does not 
consider the fact that, unlike the procedures set forth in the wiretapping statutes, at all times 
relevant to this case, there was no statute governing the use of cell site simulators. Cf. 
Criminal Procedure Article §1-203.1 (effective October 1, 2014).  Additionally, while it is 
 
13 
 
true that the wiretapping statutes, and other statutes implementing the requirements of the 
Fourth Amendment for searches, do not require a detailed recitation of the technical 
specifications of a particular device an officer plans to use, no such detail is required 
precisely because there is a statute that governs the use of the technology and describes the 
technology that is intended to be used to conduct the Fourth Amendment search.  
Considering the Majority’s example of the Maryland wiretapping statute, Cts. & Jud. Proc. 
§10-406(a) states that: 
(a) The Attorney General, State Prosecutor, or any State’s Attorney may 
apply to a judge of competent jurisdiction, and the judge, in accordance 
with the provisions of §10-408 of this subtitle, may grant an order 
authorizing the interception of wire, oral, or electronic communications 
by investigative or law enforcement officers when the interception may 
provide or has provided evidence of the commission of:  
(1) Murder; 
(2) Kidnapping; 
(3) Rape; 
(4) A sexual offense in the first or second degree; 
(5) Child abuse in the first or second degree; 
(6) Child pornography under §11-207, §11-208, or §11-208.1 of the 
Criminal Law Article; 
(7) Gambling; 
(8) Robbery under §3-402 or §3-403 of the Criminal Law Article; 
(9) A felony under Title 6, Subtitle 1 of the Criminal Law Article; 
(10) Bribery; 
(11) Extortion; 
(12) Dealing in a controlled dangerous substance, including a violation of 
§5-617 or §5-619 of the Criminal Law Article; 
(13) A fraudulent insurance act, as defined in Title 27, Subtitle 4 of the 
Insurance Article; 
(14) An offense relating to destructive devices under §4-503 of the 
Criminal Law Article; 
 
14 
 
(15) A human trafficking offense under §11-303 of the Criminal Law 
Article;  
(16) Sexual solicitation of a minor under §3-324 of the Criminal Law 
Article;  
(17) An offense relating to obstructing justice under §9-302, §9-303, or §9-
305 of the Criminal Law Article; 
(18) Sexual abuse of a minor under §3-602 of the Criminal Law Article; 
(19) A theft scheme or continuing course of conduct under §7-103(f) of the 
Criminal Law Article involving an aggregate value of property or 
sources or services of at least $10,000; 
(20) Abuse or neglect of a vulnerable adult under §3-604 or §3-605 of the 
Criminal Law Article; 
(21) An offense relating to Medicaid fraud under §§8-509 through §8-515 
of the Criminal Law Article; or 
(22) A conspiracy or solicitation to commit an offense listed in items (1) 
through (21) of this subsection. 
 
Cts. & Jud. Proc. §10-408 states, in relevant part: 
Applications for interception in writing 
(a) (1) Each application for an order authorizing the interception of a wire, 
oral, or electronic communication shall be made in writing upon oath or 
affirmation to a judge of competent jurisdiction and shall state the 
applicant’s authority to make the application. Each application shall 
include the following information: 
(i) The identity of the investigative or law enforcement officer 
making the application, and the officer authorizing the 
application; 
(ii) A full and complete statement of the facts and circumstances 
relied upon by the applicant, to justify his belief that an order 
should be issued, including: 
1. Details as to the particular offense that has been, is being, or 
is about to be committed; 
2. Except as provided in paragraph (2) of this subsection, a 
particular description of the nature and location of the 
facilities from which or the place where the communication is 
to be intercepted;  
3. A particular description of the type of communications sought 
to be intercepted; and 
 
15 
 
4. The identity of the person, if known, committing the offense 
and whose communications are to be intercepted; 
(iii)  A full and complete statement as to whether or not other 
investigative procedures have been tried and failed or why they 
reasonably appear to be unlikely to succeed if tried or to be too 
dangerous; 
(iv) A statement of the period of time for which the interception is 
required to be maintained. If the nature of the investigation is such 
that the authorization for interception should not automatically 
terminate when the described type of communication has been first 
obtained, a particular description of facts establishing probable 
cause to believe additional communications of the same type will 
occur thereafter; 
(v) A full and complete statement of the facts concerning all previous 
applications known to the individual authoring and making 
application, made to any judge for authorization to intercept wire, 
oral, or electronic communications involving any of the same 
persons, facilities or places specified in the application, and the 
action taken by the judge on each application; and 
(vi) Where the application is for the extension of an order, a statement 
setting forth the results thus far obtained from the interception, or 
a reasonable explanation of the failure to obtain the results. 
(2) (i) In the case of an application authorizing the interception of an oral  
communication, a particular description of the nature and location 
of the facilities from which or the place where the communication 
is to be intercepted is not required if the application: 
1. Is by an investigative or law enforcement officer; 
2. Is approved by the Attorney General, the State Prosecutor, or 
a State’s Attorney; 
3. Contains a full and complete statement as to why 
specification of the nature and location of the facilities from 
which or the place where the communication is to be 
intercepted is not practical; and 
4. Identifies the individual committing the offense and whose 
communications are to be intercepted. 
(ii) In the case of an application authorizing the interception of a wire 
or electronic communication, a particular description of the nature 
and location of the facilities from which or the place where the 
communication is to be intercepted is not required if the 
application: 
1. Is by an investigative or law enforcement officer; 
2. Is approved by the Attorney General, the State Prosecutor, or 
a State’s Attorney; 
 
16 
 
3. Identifies the individual believed to be committing the 
offense and whose communications are to be intercepted; 
4. Makes a showing that there is probable cause to believe that 
the individual’s actions could have the effect of thwarting 
interception from a specified facility; and 
5. Specifies that interception will be limited to any period of 
time when the investigative or law enforcement officer has a 
reasonable, articulable belief that the individual identified in 
the application will be proximate to the communication 
device and will be using the communication device through 
which the communication will be transmitted. 
 
* 
* 
* 
 
Grounds for ex parte interception order 
 
(c) (1) Upon the application the judge may enter an ex parte order, as 
requested or as modified, authorizing interception of wire, oral, or 
electronic communications within the territorial jurisdiction permitted 
under paragraphs (2) and (3) of this subsection, if the judge determines 
on the basis of the facts submitted by the applicant that: 
(i) There is probable cause for belief that an individual is committing, 
has committed, or is about to commit a particular offense 
enumerated in §10-406 of this subtitle; 
(ii) There is probable cause for belief that particular communications 
concerning that offense will be obtained through interception; 
(iii) Normal investigative procedures have been tried and have failed 
or reasonable appear to be unlikely to succeed if tried or to be too 
dangerous; and 
(iv) There is probable cause for belief: 
1. That the facilities from which, or the place where, the wire, 
oral, or electronic communications are to be intercepted are 
being used, or are about to be used, in connection with the 
commission of the offense, or are leased to, listed in the name 
of, or commonly used by this person in accordance with 
subsection (a)(1) of this section; or 
2. That the actions of the individual whose communications are 
to be intercepted could have the effect of thwarting an 
interception from a specified facility in accordance with 
subsection (a)(2) of this section. 
(2) Except as provided in paragraphs (3) and (4) of this subsection, an ex 
parte order issued under paragraph (1) of this subsection may 
authorize the interception of wire, oral, or electronic communications 
 
17 
 
only within the territorial jurisdiction of the court in which the 
application was filed. 
(3) If an application for an ex parte order is made by the Attorney General, 
the State Prosecutor, or a State’s Attorney, an order issued under 
paragraph (1) of this subsection may authorize the interception of 
communications received or sent by a communication device 
anywhere within the State so as to permit the interception of the 
communications regardless of whether the communication device is 
physically located within the jurisdiction of the court in which the 
application was filed at the time of the interception. The application 
must allege that the offense being investigated may transpire in the 
jurisdiction of the court in which the application is filed. 
(4) In accordance with this subsection, a judge of competent jurisdiction 
may authorize continued interception within the State, both within and 
outside the judge’s jurisdiction, if the original interception occurred 
within the judge’s jurisdiction. 
 
Contents of ex parte interception orders 
 
(d) (1) Each order authorizing the interception of any wire, oral, or electronic      
communication shall specify: 
(i) The identity of the person, if known or required under subsection 
(a)(2) of this section, whose communications are to be intercepted; 
(ii) The nature and location of the communications facilities as to 
which, or the place where, authority to intercept is granted, if 
known; 
(iii) A particular description of the type of communications sought to 
be intercepted, and a statement of the particular offense to which 
it relates; 
(iv) The identity of the agency authorized to intercept the 
communications, and of the person authorizing the application; 
and 
(v) The period of time during which the interception is authorized, 
including a statement as to whether or not the interception shall 
automatically terminate when the described communication has 
been first obtained. 
(2) An order authorizing the interception of a wire, oral, or electronic 
communication, upon request of the applicant, shall direct that a 
provider of wire or electronic communication service, landlord, 
custodian or other person furnish the applicant forthwith all 
information, facilities, and technical assistance necessary to 
accomplish the interception unobtrusively and with a minimum of 
interference with the services that the service provider, landlord, 
 
18 
 
custodian, or person is according the person whose communications 
are to be intercepted. Any provider of wire or electronic 
communication service, landlord, custodian or other person 
furnishing the facilities or technical assistance shall be compensated 
therefor by the applicant for reasonable expenses incurred in 
providing facilities or assistance. 
 
* 
* 
* 
 
Motions to suppress by aggrieved persons 
 
(i) (1) Any aggrieved person in any trial, hearing, or proceeding in or before  
any court, department, officer, agency, regulatory body, or other 
authority of this State or a political subdivision thereof, may move to 
suppress the contents of any intercepted wire, oral, or electronic 
communication, or evidence derived therefrom, on the grounds that: 
(i) The communication was unlawfully intercepted; 
(ii) The order of authorization under which it was intercepted is 
insufficient on its face, or was not obtained or issued in strict 
compliance with this subtitle; or 
(iii) The interception was not made in conformity with the order of 
authorization. 
 
* 
* 
* 
 
Cts. & Jud. Proc. §10-401(10) defines “[i]ntercept” as “the aural or other acquisition 
of the contents of any wire, electronic, or oral communications through the use of any 
electronic, mechanical, or other device.”  Cts. & Jud. Proc. §10-401(5)(i) defines 
“[e]lectronic communication” as “any transfer of signs, writing, images, sounds, data, or 
intelligence of any nature transmitted in whole or in part by a wire, radio, electromagnetic, 
photoelectronic, or photooptical system.” Sub-paragraph (ii) also states that “electronic 
communication does not include: (1) [a]ny wire or oral communication; (2) [a]ny 
communication made through a tone-only paging device; or (3) [a]ny communication from 
a tracking device.”  An “[o]ral communication” is defined to mean “any conversation or 
 
19 
 
words spoken to or by any person in a private conversation.” Cts. & Jud. Proc. §10-
401(13)(i).  The statutes also defines “[w]ire communication” as  
any aural transfer made in whole or in part through the use of facilities for 
the transmission of communications by the aid of wire, cable, or other like 
connection between the point of origin and the point of reception (including 
the use of a connection in a switching station) furnished or operated by any 
person licensed to engage in providing or operating such facilities for the 
transmission of communications. 
 
Cts. & Jud. Proc. §10-401(18).  Finally, Cts. & Jud. Proc. §10-401(8) defines “[e]lectronic, 
mechanical, or other device” to mean  
any device or electronic communication other than: 
 
(i) Any telephone or telegraph instrument, equipment or other facility for the 
transmission of electronic communications or any component thereof, 
(a) furnished to the subscriber or user by a provider of wire or electronic 
communication service in the ordinary course of its business and 
being used by the subscriber or user in the ordinary course of its 
business or furnished by the subscriber or user for connection to the 
facilities of the service and used in the ordinary course of its business; 
or 
(b) being used by a communications common carrier[5] in the ordinary 
course of its business, or by an investigative or law enforcement 
officer in the ordinary course of his duties; or 
(ii) A hearing aid or similar device being used to correct subnormal hearing 
to not better than normal. 
 
As noted, supra, and in contrast to the above-quoted statutory scheme for 
wiretapping in the State of Maryland, the order relied on by the police in the present case 
was based on the Maryland Pen Register Statute, which exclusively describes the pen 
register and trap & trace technologies and neither of which remotely describe cell site 
                                              
5 The statute defines a “[c]ommunications common carrier” as “any person engaged 
as a common carrier for hire in the transmission of wire or electronic communications.” 
Cts. & Jud. Proc. §10-401(3). 
 
20 
 
simulator technology.  See Cts. & Jud. Proc. §10-4B-01(c)(1), (d)(1).  Thus, while as a 
general matter it is true that when a law enforcement officer is applying for a search warrant 
pursuant to a statute that “implement[s] the requirements of the Fourth Amendment for 
searches” he or she is not required to “go beyond the requirements of those statutes to detail 
the particular technology utilized.”  See Maj. Slip Op. at 50 n. 67; see also Dalia, 441 U.S. 
at 257, 99 S. Ct. at 1693.  Where, as in this case, however, a law enforcement officer does 
not rely on a statute that details the type of technology the warrant, or order in this case, 
would apply to, he or she is required to provide a description of the technology he or she 
intends to use in sufficient detail for an issuing judge to appreciate the scope of the potential 
infringement on a person’s Fourth Amendment privacy interests, and the officer’s failure 
to do so results in a warrant so deficient on its face that the good faith exception to the 
exclusionary rule should not apply. 
Accordingly, I conclude it was unreasonable for the police officers in this case to 
presume that the Pen Register/Trap & Trace and Cellular Tracking Device order authorized 
them to use the Hailstorm device.  The circuit court correctly suppressed the evidence that 
was subsequently discovered in the Respondent’s home. 
Judges Greene and Adkins have authorized me to state that they join in this opinion.