FOR PUBLICATION

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA, 

Plaintiff-Appellant, 

 v. 

DONNELL ARTIS; CHANTA HOPKINS, 

AKA Askari Aquil Mohammed, 

Defendants-Appellees.

No. 18-10246 

D.C. No. 3:16-cr-00477-VC-1 

OPINION

Appeal from the United States District Court

for the Northern District of California

Vince Chhabria, District Judge, Presiding

Argued and Submitted January 11, 2019

Pasadena, California

Before: A. Wallace Tashima and Paul J. Watford, Circuit Judges, and Eduardo C. 

Robreno,* District Judge.

WATFORD, Circuit Judge:

Federal agents may have violated California law when they executed two 

search warrants issued by state court judges. California law authorizes “peace 

officers” to execute search warrants, but excludes federal law enforcement officers 

 

* The Honorable Eduardo C. Robreno, United States District Judge for 

the Eastern District of Pennsylvania, sitting by designation.

FILED

MAR 27 2019

MOLLY C. DWYER, CLERK

U.S. COURT OF APPEALS
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from the definition of that term. This apparent violation of state law, we conclude, 

does not render the warrants invalid under the Fourth Amendment. One of the 

warrants, however, was not supported by probable cause, and the evidence seized 

pursuant to that warrant must be suppressed.

I

At the time of the events relevant to this appeal, defendants Donnell Artis 

and Chanta Hopkins were alleged confederates engaged in credit card fraud and 

identity theft. Both were also fugitives from justice with outstanding warrants for 

their arrest on state law charges. 

Artis and Hopkins came to the attention of Stonie Carlson, a Special Agent 

with the Federal Bureau of Investigation assigned to the Pacific Southwest 

Regional Fugitive Task Force, a joint federal-state task force operating under the 

direction of the United States Marshals Service. See 34 U.S.C. § 41503(a). Agent 

Carlson set out to find the two men, both of whom were believed to be in or around 

Oakland, California. Officers from the Oakland Police Department informed 

Agent Carlson that Artis and Hopkins could often be found hanging out at a 

particular liquor store in Oakland, and Agent Carlson spotted Artis there one day.

When Agent Carlson and his partner tried to arrest Artis, a brief scuffle ensued, 

during which Artis dropped his cell phone. Artis broke away and managed to 

escape on foot, leaving his cell phone behind. Agent Carlson returned to the liquor 
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store and retrieved the phone, a seizure rendered lawful by Artis’ abandonment of

the phone when he fled from agents attempting to arrest him. 

In his capacity as a member of the fugitive task force, Agent Carlson applied 

for a warrant to search Artis’ cell phone. Although he could have asked a federal 

magistrate judge to issue the warrant under Federal Rule of Criminal Procedure 41, 

Agent Carlson submitted the application to a judge of the Alameda County 

Superior Court. Agent Carlson later explained that he did so because Artis’ 

outstanding arrest warrants were for state law offenses and at the time Agent 

Carlson was not contemplating filing federal charges against Artis. For reasons 

unexplained in the record, Agent Carlson did not predicate the warrant application 

on Artis’ status as a known fugitive, which would have provided a basis to search 

his phone for information useful in finding him. Instead, Agent Carlson’s affidavit 

recounted facts establishing probable cause to believe that Artis was engaged (with 

Hopkins) in a conspiracy to commit credit card fraud under state law. He 

requested permission to search Artis’ cell phone for evidence of that offense.

The Alameda County Superior Court judge issued a warrant, directed to 

“any peace officer in Alameda County,” authorizing a search of Artis’ cell phone

for “evidence of a crime”—in particular, for eight specified categories of 

information, such as stored email and text messages “[c]ontaining any references 

to fraud or related criminal activity.” Agent Carlson found that he lacked the 
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technical expertise to execute the warrant himself, but after a few days’ delay he 

enlisted the help of a fellow FBI agent who was able to extract the relevant 

information from Artis’ phone. Based in part on that evidence, the government 

charged Artis with the federal firearms and identity-theft offenses he faces in this 

case. 

Two days after obtaining the warrant to search Artis’ phone, but before he 

had been able to execute it, Agent Carlson applied for a second search warrant, this 

one targeting Hopkins. Agent Carlson again applied for the warrant in his capacity 

as a member of the fugitive task force, and he again submitted the application to an 

Alameda County Superior Court judge rather than a federal magistrate judge. 

Agent Carlson predicated the Hopkins warrant application solely on Hopkins’ 

status as a fugitive with an outstanding warrant for his arrest. The application 

sought authorization to use a cell-site simulator to track the location of a cell phone 

assigned the number (832) 763-5555. Agent Carlson’s affidavit recounted facts 

establishing probable cause to believe that Hopkins was then using the targeted cell 

phone. 

An Alameda County Superior Court judge issued a search warrant, also 

directed to “any peace officer in the County of Alameda,” authorizing use of a cellsite simulator for a period of 30 days to track the location of the targeted cell 
Page 5 of 22

phone. The warrant stated that federal agents “employed by the United States 

Marshals Service are authorized to assist in the service of this search warrant.” 

A federal agent working as part of the fugitive task force deployed the cellsite simulator in accordance with the warrant. Through use of the device and 

additional investigative work, task force agents determined that Hopkins lived in a 

particular apartment building in San Francisco. They arrested him as he left the

apartment and found incriminating evidence during a search incident to arrest. 

That evidence formed the basis for a search warrant issued by a San Francisco 

County Superior Court judge authorizing a search of Hopkins’ apartment. The 

apartment search yielded much of the evidence underlying the federal drugtrafficking and identity-theft charges filed against Hopkins in this case. 

Artis and Hopkins filed separate motions to suppress that challenged the 

validity of their respective Alameda County Superior Court search warrants. Both 

motions argued that: (1) the warrants were invalid because they were executed by 

officials not authorized to execute warrants under California law; and (2) the

warrants were not supported by probable cause. 

After conducting an evidentiary hearing at which Agent Carlson testified, 

the district court granted both motions to suppress. The court agreed with the 

defendants that “under California law, federal law enforcement officers are not 

permitted to execute search warrants issued by California state judges.” United 
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States v. Artis, 315 F. Supp. 3d 1142, 1145 (N.D. Cal. 2018). The court concluded 

that federal agents impermissibly executed both warrants but recognized that 

suppression would not be justified on the basis of this state law violation alone. Id.

at 1143–44. In addition, though, the court held that neither warrant was supported 

by probable cause, and it declined to apply the good-faith exception to the 

exclusionary rule in view of a “string of errors” embodied in the two warrant 

applications submitted by Agent Carlson. 

As permitted under 18 U.S.C. § 3731, the government filed an interlocutory 

appeal from the district court’s suppression ruling.

II

The outcome of this appeal turns on whether the challenged searches 

violated the Fourth Amendment, which protects the people’s right “to be secure in 

their persons, houses, papers, and effects, against unreasonable searches and 

seizures.” Certain searches must be conducted pursuant to a warrant to be deemed 

reasonable. The search of Artis’ cell phone definitely required a warrant, see Riley 

v. California, 573 U.S. 373 (2014), and we will assume (as the government has) 

that use of a cell-site simulator to track the location of Hopkins’ cell phone also 

required a warrant. But both of the searches in question were conducted pursuant 

to a warrant. To establish a Fourth Amendment violation, then, the defendants 

must succeed in showing either that the warrants were invalid under the Fourth 
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Amendment or that, even if valid, the warrants were executed in a manner that

rendered the searches unreasonable.

The defendants have confined themselves to the first line of argument, 

framing their challenge solely as an attack on the validity of their respective 

warrants. They do not contend that anything about the manner of execution 

rendered the searches unreasonable. They have not asserted, for example, that the 

scope of the searches conducted by the agents exceeded what the warrants 

authorized, or that the agents seized evidence not described in the warrants. Their 

only complaint about the manner in which the warrants were executed is that 

federal agents conducted the searches instead of officials designated as “peace 

officers” under state law. But the identity of the executing officers—federal agents 

versus peace officers—does not implicate any interest protected by the Fourth 

Amendment. No greater intrusion upon protected privacy or property interests 

occurred by virtue of the fact that the searches were conducted by federal agents as 

opposed to, say, city police officers. Cf. Wilson v. Layne, 526 U.S. 603, 614

(1999) (holding that police violated the Fourth Amendment by allowing members 

of the news media into a home during the execution of a warrant, due to the 

heightened intrusion upon privacy interests caused by their unauthorized presence 

and non-law-enforcement purpose).
Page 8 of 22

To succeed here, the defendants must demonstrate that their respective

search warrants were invalid under the Fourth Amendment. The Amendment’s 

Warrant Clause provides that a warrant may be issued only “upon probable cause, 

supported by Oath or affirmation, and particularly describing the place to be 

searched, and the persons or things to be seized.” The Supreme Court has held that 

this language imposes three requirements for issuance of a valid search warrant. 

First, the warrant must be issued by a neutral and detached magistrate. Dalia v. 

United States, 441 U.S. 238, 255 (1979).1 Second, the warrant must be supported 

by “probable cause to believe that the evidence sought will aid in a particular 

apprehension or conviction for a particular offense.” Id. (internal quotation marks 

omitted). And third, the warrant must describe the things to be seized and the 

place to be searched with particularity. Id.

Only the second of these requirements—whether the warrants were 

supported by probable cause—is open to serious challenge. (We address that issue 

in the next section.) As to the first requirement, both warrants were issued by 

neutral and detached judges of the Alameda County Superior Court who were 

authorized to issue search warrants in the jurisdiction where the warrants were to 

 

1 Our court has recently held that, in addition, the magistrate must be authorized by 

law to issue warrants in the jurisdiction where the warrant will be executed. 

United States v. Henderson, 906 F.3d 1109, 1117 (9th Cir. 2018). 
Page 9 of 22

be executed.2 Neither Artis nor Hopkins challenges the third requirement 

demanding sufficient particularity.

The defendants argue that we should add a fourth requirement to the list. 

They contend that a state court warrant is valid for Fourth Amendment purposes 

only if the officers who execute it are authorized to do so under state law, and that 

the warrants at issue here are invalid because they were issued to and executed by 

federal agents in contravention of California law. 

Before addressing the defendants’ argument, it is useful to separate the 

warrant process into its three distinct phases: application, issuance, and execution. 

See United States v. Freeman, 897 F.2d 346, 348 (8th Cir. 1990). First, someone 

applies for a warrant, typically a law enforcement officer or an attorney for the 

government. Second, the magistrate issues the warrant, directing it to a particular 

person or class of people. Finally, someone executes the warrant by conducting the

search or seizure that the warrant authorizes.

 

2 Hopkins contends that the judge who issued his warrant exceeded the scope of 

her authority because agents ended up deploying the cell-site simulator in 

neighboring San Francisco County. But Hopkins points to no provision of 

California law that limits a Superior Court judge’s authority to issue a search 

warrant to the territorial boundaries of the county in which the judge sits. The few 

California cases addressing similar issues seem to point in the opposite direction. 

See, e.g., People v. Fleming, 631 P.2d 38, 42 (Cal. 1981). The district court has 

not yet addressed this argument, however, and Hopkins remains free to renew it on 

remand. 
Page 10 of 22

The defendants really contest only the third phase of this process. They do 

not contend that Agent Carlson violated California law by applying for the 

warrants, nor could they, for California law places no limits on who may apply for 

a search warrant. See People v. Bell, 53 Cal. Rptr. 2d 156, 170–71 (Ct. App. 

1996). Nor can they contend that the warrants were improperly issued under state 

law. It’s true that under California law a search warrant must be directed to a 

“peace officer,” Cal. Penal Code §§ 1523, 1528(a), 1530, and that federal law 

enforcement officers do not qualify as peace officers, § 830.8(a). But the warrants 

in this case were directed, as state law requires, “to any peace officer” in Alameda 

County. The defendants are thus wrong in asserting that the warrants were 

improperly issued to a federal agent.

Whether the warrants were improperly executed by federal agents is a closer 

question. California law requires search warrants to be executed by “peace 

officers,” but federal agents may assist a peace officer in executing a search 

warrant, provided the federal agent is acting “in aid of the officer on his requiring 

it, he being present and acting in its execution.” Cal. Penal Code § 1530. As the 

defendants argue, it seems doubtful that this requirement was satisfied here, 

although California courts do not appear to have addressed how strictly this 
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provision should be construed when federal agents execute a search warrant as 

members of a joint federal-state task force that includes peace officers.3

We find it unnecessary to decide whether federal agents violated California 

law by executing the Artis and Hopkins warrants. Even if such a violation 

occurred, the warrants would still be valid under the Fourth Amendment. An 

otherwise properly issued search warrant is not rendered void for Fourth 

Amendment purposes merely because it was executed by law enforcement officers 

who lacked warrant-executing authority under state law. See United States v. 

Green, 178 F.3d 1099, 1106 (10th Cir. 1999); United States v. Gilbert, 942 F.2d 

1537, 1540–41 (11th Cir. 1991); Freeman, 897 F.2d at 348–49.

4

Alternatively, the defendants argue that the validity of the warrants should 

be assessed under Federal Rule of Criminal Procedure 41, which establishes the 

procedures for issuance of search warrants in federal court. This argument lacks 

merit as well. Rule 41 applies only when a search is “federal in character.” United 

 

3 The Hopkins cell-site simulator warrant, as noted above, did provide that federal 

agents “employed by the United States Marshals Service are authorized to assist in 

the service of this warrant.”

4

In Perry v. United States, 14 F.2d 88 (9th Cir. 1926), we held that the Fourth 

Amendment was violated when officers without statutory authorization executed a 

search warrant. Id. at 89. But Perry rested on the Prohibition-era view that a 

lawful Fourth Amendment search or seizure required compliance with an 

authorizing statute. See Orin S. Kerr, Cross-Enforcement of the Fourth 

Amendment, 132 Harv. L. Rev. 471, 501 (2018). Perry’s holding on that point did 

not survive Virginia v. Moore, 553 U.S. 164, 168 (2008).
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States v. Martinez-Garcia, 397 F.3d 1205, 1213 (9th Cir. 2005). The fact that 

federal agents were involved in conducting the search is a relevant consideration,

but not sufficient on its own to trigger the rule’s application. United States v. 

Palmer, 3 F.3d 300, 303 (9th Cir. 1993). The search must be tied to an 

investigation into potential violations of federal law. See United States v. Duval, 

742 F.3d 246, 254 (6th Cir. 2014); United States v. Claridy, 601 F.3d 276, 282–83 

(4th Cir. 2010). The searches in question here do not fit that bill. Agent Carlson 

sought the warrants in furtherance of an investigation into state law violations 

alone—in Artis’ case, to investigate an alleged conspiracy to commit credit card 

fraud under state law, and in Hopkins’ case, to aid in locating a fugitive wanted on 

state law charges. At the time Agent Carlson applied for the warrants, no 

discussions were underway about bringing federal charges against either Artis or 

Hopkins. The provisions of Rule 41 therefore do not apply.

III

The sole remaining issue is whether the warrants are invalid under the 

Fourth Amendment because they were not supported by probable cause. The 

district court held both warrants invalid on this basis, and further held that the 

government could not rely on the good-faith exception to the exclusionary rule. 

We agree with the district court’s conclusion only as to the Artis warrant, which 

we address first.
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A

Agent Carlson’s application for the Artis warrant requested authorization to 

search his cell phone for evidence of his involvement in a conspiracy to commit 

credit card fraud, and the supporting affidavit accordingly sought to establish 

probable cause to believe that Artis was engaged in that offense. In reviewing the 

adequacy of the probable cause showing, we must assess whether probable cause 

has been shown with respect to the offense asserted as the basis for issuing the 

warrant; whether Agent Carlson’s affidavit established probable cause with respect 

to some other offense is irrelevant. See United States v. $186,416.00 in U.S. 

Currency, 590 F.3d 942, 948 (9th Cir. 2010). We therefore reject the 

government’s assertion that the warrant may be upheld because Agent Carlson’s 

affidavit established probable cause to believe that Artis was a fugitive and that a 

search of his cell phone would yield evidence useful in finding him.

The first obstacle the government faces in attempting to defend the adequacy 

of the probable cause showing is that the most probative evidence mentioned in 

Agent Carlson’s affidavit must be disregarded. The affidavit describes an earlier 

search that occurred when officers attempted to execute a warrant for Artis’ arrest

at his girlfriend’s apartment. According to the affidavit, when the officers knocked 

on the front door to the apartment, it swung open. Concerned that someone might 

be inside and in need of help, the officers performed what Agent Carlson termed a 
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“safety sweep” of the apartment. Although the officers found no one inside, in the 

course of the safety sweep they observed “several counterfeit credit cards” bearing 

Artis’ name on a kitchen counter. (The affidavit does not explain how the officers 

were able to determine, from the face of the cards alone, that they were indeed 

counterfeit.) The officers’ observation of the counterfeit credit cards obviously 

provided strong support for the conclusion that Artis was engaged in some sort of 

credit card fraud, and the judge who issued the warrant no doubt relied heavily on 

that evidence in deciding that probable cause had been shown.

Artis contends here, as he did below, that the search of his girlfriend’s 

apartment violated his Fourth Amendment rights. He asserts as a factual matter 

that he was an overnight guest in his girlfriend’s apartment. Thus, as a legal 

matter, the officers could not rely on Artis’ arrest warrant alone as authorization to 

enter his girlfriend’s apartment: They needed a search warrant or probable cause 

to believe he was present at the time of the search, neither of which, he contends, 

they had. See United States v. Gorman, 314 F.3d 1105, 1114–15 (9th Cir. 2002). 

Artis further suggests that the officers lied when they stated the front door to the 

apartment had been left ajar, eliminating any basis for their claim that exigent 

circumstances justified a warrantless entry. 

The government conceded below that the district court should disregard the 

evidence discovered during the apartment search when assessing whether probable 
Page 15 of 22

cause had been shown, albeit not on the ground that the officers’ entry was 

unlawful but rather because the counterfeit credit cards may not have been found in 

plain view, as Agent Carlson’s affidavit asserted. In light of the government’s 

refusal to defend the legality of the apartment search, the district court properly 

struck from Agent Carlson’s affidavit any reference to the counterfeit credit cards. 

We will follow the same course here. Having excised evidence from the 

supporting affidavit, we do not defer, as we normally would, to the issuing 

magistrate’s determination that probable cause existed. In that scenario, we have 

nothing to which we could defer, as the magistrate made no determination about 

whether probable cause exists on the set of facts now before us. See United States 

v. Kelley, 482 F.3d 1047, 1051 (9th Cir. 2007). Instead, we must “determine on 

our own whether the remaining portions of the affidavit support a finding of 

probable cause.” United States v. Job, 871 F.3d 852, 864 (9th Cir. 2017).

The remaining portions of Agent Carlson’s affidavit fail to support a finding 

of probable cause that Artis was engaged in credit card fraud. The affidavit 

recounts the following facts: (1) Artis had outstanding arrest warrants for, among

other offenses, identity theft; (2) Artis fled from Agent Carlson and his partner 

when they attempted to arrest him; and (3) Artis is a close associate of Hopkins, 

who also had an outstanding warrant for his arrest. Considered together, these 
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facts fall far short of establishing probable cause regarding credit card fraud. They

establish little more than Artis’ status as a fugitive from justice.

The affidavit included one additional piece of evidence that merits separate 

discussion. Agent Carlson stated, without further elaboration, that a cooperating 

witness had informed him that “Artis and Hopkins are involved in a conspiracy to 

commit credit card fraud and that they are in constant communication with each 

other in furtherance of the crime.” If credited, this information would obviously 

suffice to establish probable cause to believe that Artis was engaged in credit card 

fraud. But other than the evidence obtained from the unlawful search of Artis’ 

girlfriend’s apartment, which we must disregard, the affidavit offers no basis for 

concluding that the information provided by the unnamed informant was reliable. 

The affidavit does not state the informant’s basis of knowledge or provide any 

information about the informant’s reliability in the past. See Illinois v. Gates, 462 

U.S. 213, 233 (1983); United States v. Bishop, 264 F.3d 919, 925 (9th Cir. 2001). 

Nor does the affidavit contain any information corroborating what the informant 

said. See Gates, 462 U.S. at 242–43; Bishop, 264 F.3d at 925–26. 

Contrary to the government’s argument, Artis’ outstanding arrest warrant for 

identity theft does not provide the necessary corroboration. Although identity theft 

and credit card fraud are potentially related offenses, without knowing more about 

the age of the warrant and the nature of the underlying conduct, no inferences can 
Page 17 of 22

be drawn about whether the existence of the warrant bolstered the credibility of the 

informant’s bare accusation.

As the district court held, after excising the evidence illegally obtained, the 

remaining portions of Agent Carlson’s affidavit fail to establish a “fair probability” 

that evidence of credit card fraud would be found on Artis’ cell phone. Gates, 462 

U.S. at 238. The search of the phone pursuant to an invalid warrant violated Artis’ 

Fourth Amendment rights, requiring suppression of the fruits of that search unless 

the government can demonstrate that the good-faith exception to the exclusionary 

rule applies.

The good-faith exception precludes suppression of evidence seized by 

officers who acted “in objectively reasonable reliance” on a search warrant that is 

later declared invalid. United States v. Leon, 468 U.S. 897, 922 (1984). However, 

we have held that the good-faith exception may not be invoked when “the search 

warrant was issued in part on the basis of evidence obtained from an illegal 

search.” United States v. Wanless, 882 F.2d 1459, 1466–67 (9th Cir. 1989); see 

also United States v. Vasey, 834 F.2d 782, 789 (9th Cir. 1987). That rule would 

foreclose the government’s reliance on the good-faith exception here.

We acknowledge that the Supreme Court’s precedent on application of the 

good-faith exception has shifted somewhat since we decided Vasey and Wanless. 

When those cases were decided, the good-faith exception had been held to apply 
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only when the police acted in reasonable reliance on mistakes made by others, such 

as the magistrate who issued the defective warrant in Leon. It was not yet clear 

whether the good-faith exception would apply when the police acted in reliance on 

their own mistakes. Thus, in rejecting application of the good-faith exception in 

Vasey, we stressed that “[t]he constitutional error was made by the officer in this 

case, not by the magistrate as in Leon.” 834 F.2d at 789. The good-faith exception 

could not apply to the fruit of that constitutional violation, including evidence 

seized under the resulting warrant.

The Supreme Court has since held that the good-faith exception can apply 

even when the police are responsible for the mistake that led to an unlawful search 

or seizure. In Herring v. United States, 555 U.S. 135 (2009), the Court applied the 

good-faith exception to uphold the admission of evidence seized during a 

concededly unlawful arrest, even though the arrest occurred because law 

enforcement officials negligently failed to remove a recalled warrant from their 

database. Id. at 138, 147–48. The Court held that, to justify suppression as a 

remedy for a Fourth Amendment violation, “police conduct must be sufficiently 

deliberate that exclusion can meaningfully deter it, and sufficiently culpable that 

such deterrence is worth the price paid by the justice system.” Id. at 144. The 

“isolated negligence” at issue in Herring, the Court concluded, did not meet that 

standard. Id. at 137.
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In light of Herring, we can no longer declare the good-faith exception 

categorically inapplicable whenever a search warrant is issued on the basis of 

evidence illegally obtained as a result of constitutional errors by the police. We 

must instead determine whether the police misconduct that led to discovery of the 

illegally obtained evidence is itself subject to the good-faith exception. If it is, 

suppression of the evidence seized pursuant to the warrant will not be justified. 

But if the police misconduct is not protected by the good-faith exception, 

suppression is the appropriate remedy. The misconduct will by definition be 

“sufficiently deliberate” that it can be deterred through application of the 

exclusionary rule, and “sufficiently culpable” to warrant exclusion as a remedy. 

Id. at 144. And because the illegally obtained evidence will necessarily have been 

decisive in establishing probable cause (otherwise there would be no need to resort 

to the good-faith exception), evidence discovered pursuant to the warrant will be 

the fruit of that earlier illegality and subject to suppression for that reason. See 

Wong Sun v. United States, 371 U.S. 471, 485 (1963).

Under this standard, suppression is warranted here. The government bears 

the burden of showing that the good-faith exception applies. See United States v. 

Underwood, 725 F.3d 1076, 1085 (9th Cir. 2013). In this case, it must show that 

the good-faith exception would have applied to render the counterfeit credit cards

evidence admissible. The government cannot carry that burden because it has 
Page 20 of 22

made no effort to defend the legality of the search that yielded the evidence in 

question. The search violated the Fourth Amendment either because the officers 

lacked authority to enter Artis’ girlfriend’s apartment in the first place, as Artis 

contends, or because the officers did not discover the credit cards in plain view, as 

the government has effectively conceded. Either way, the police discovered the 

evidence through conduct that, on this record at least, is plainly unconstitutional, in 

contrast to the kind of “isolated negligence” at issue in Herring. That misconduct 

is sufficiently deliberate that it can be deterred through exclusion of the fruit of the 

illegal search, and sufficiently culpable to warrant imposition of that sanction.

The evidence seized pursuant to the Artis warrant must be suppressed as the 

fruit of the illegal search of his girlfriend’s apartment. As we have held,

observation of the counterfeit credit cards was crucial to issuance of the warrant, 

since without that illegally obtained evidence probable cause was lacking. We 

therefore affirm the district court’s order granting Artis’ motion to suppress.

B

We next address whether probable cause supported the Hopkins warrant, 

which authorized use of a cell-site simulator to track the location of the cell phone 

using the number (832) 763-5555. 

The Hopkins warrant was predicated solely on his status as a fugitive from 

justice and the government’s legitimate interest in apprehending him. No one 
Page 21 of 22

disputes that tracking the location of a particular cell phone will likely assist in 

locating the person using that phone. The warrant application therefore needed to 

establish probable cause to believe two things: that Hopkins was in fact a fugitive, 

and that he was currently using the targeted cell phone. Hopkins challenges only 

the adequacy of the showing as to his use of the phone. 

Agent Carlson’s affidavit recounts the following facts. After he obtained 

possession of Artis’ cell phone, the phone received “several incoming calls” from 

the number (832) 763-5555. (During the evidentiary hearing, Agent Carlson 

clarified that he saw several notifications on the locked screen of Artis’ phone 

reflecting contacts from the targeted cell phone, at least one of which was an 

incoming call. This clarification does not affect the analysis.) A search of a law 

enforcement database revealed that the number was issued to an unknown 

subscriber with Verizon Wireless. Agent Carlson contacted a cooperating witness 

who told him that Hopkins’ cell phone number was (832) 763-5555 and that the 

cooperating witness had learned this fact from Artis—someone who, as a “known 

associate” of Hopkins, would presumably know the latter’s cell phone number. If 

credited, this information from the informant would easily establish probable cause 

to believe that Hopkins was using the targeted cell phone.

Hopkins contends that the affidavit provided no basis for crediting the 

informant as reliable because nothing disclosed in the affidavit corroborated the 
Page 22 of 22

informant’s tip. We disagree. The informant’s tip was corroborated by the fact 

that someone using the number attributed to Hopkins attempted to contact Artis, 

one of Hopkins’ associates. Had the informant simply made up a phone number 

for Hopkins, it would be a remarkable coincidence to find a missed call from that 

number on Artis’ cell phone. Hopkins assumes that Agent Carlson told the 

informant that several notifications from the number (832) 763-5555 had appeared 

on Artis’ phone and then asked the informant to confirm whether that number 

belonged to Hopkins. If accurate, this sequence of events would undoubtedly 

undermine the corroborative value of the contacts from the targeted cell phone. 

But nothing in the affidavit supports Hopkins’ version of events. And despite 

having had an opportunity to cross-examine Agent Carlson at the evidentiary 

hearing, Hopkins can point to nothing in the record to support his factual narrative. 

The informant’s tip plus the corroborating notifications found on Artis’ phone

sufficed—although barely—to establish probable cause that Hopkins was using the 

targeted cell phone.

Because the Hopkins warrant is valid under the Fourth Amendment, we need 

not address whether the good-faith exception to the exclusionary rule applies as to 

this warrant. We reverse the district court’s order granting Hopkins’ motion to 

suppress.

AFFIRMED IN PART, REVERSED IN PART, and REMANDED.