RECOMMENDED FOR FULL-TEXT PUBLICATION

Pursuant to Sixth Circuit I.O.P. 32.1(b)

File Name: 19a0126p.06

UNITED STATES COURT OF APPEALS

FOR THE SIXTH CIRCUIT

UNITED STATES OF AMERICA,

Plaintiff-Appellee,

v.

TIMOTHY IVORY CARPENTER,

Defendant-Appellant.

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No. 14-1572

On Remand from the United States Supreme Court.

United States District Court for the Eastern District of Michigan at Detroit.

No. 2:12-cr-20218-4—Sean F. Cox, District Judge.

Decided and Filed: June 11, 2019

Before: GUY, KETHLEDGE, and STRANCH, Circuit Judges.

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OPINION

_________________

JANE B. STRANCH, Circuit Judge. This case returns on remand from the Supreme 

Court. In our prior opinion, the majority held that the Government’s warrantless collection of 

Timothy Ivory Carpenter’s cell-site location information (CSLI) did not violate the Fourth 

Amendment. The Supreme Court disagreed. The unconstitutionality of the Government’s 

search was not clear until after the Supreme Court reversed our decision, which leads us to the 

question of whether the FBI agents who obtained Carpenter’s CSLI acted in good faith. Because 

these agents reasonably relied on the Stored Communications Act (SCA), we AFFIRM the 

judgment of the district court.

>
No. 14-1572 United States v. Carpenter Page 2

I. BACKGROUND

A. CSLI and the SCA

We begin with the basics of CSLI and the related legal framework. CSLI refers to the 

time-stamped location records generated each time a wireless device communicates with a 

carrier’s network by connecting to the nearest antenna, known as a “cell site.” Carpenter v. 

United States (Carpenter II), 138 S. Ct. 2206, 2211 (2018). As cell phone usage has become 

ubiquitous, cell sites have proliferated. Id. Each new cell site, in turn, enhances the precision of 

cell phone owners’ CSLI. Even in the time elapsed between Carpenter’s trial and the Supreme 

Court’s decision in Carpenter II, CSLI had “rapidly approach[ed] GPS-level precision.” Id. at 

2219; see also id. (“[W]ith new technology measuring the time and angle of signals hitting their 

towers, wireless carriers already have the capability to pinpoint a phone’s location within 50 

meters.”). 

The imminent launch of fifth-generation wireless technology, known as 5G, promises to 

multiply the number of cell sites in this country. Wireless networks once designed to carry cell 

phone traffic will soon support an unprecedented number of devices connected across industries, 

including autonomous vehicles, smart homes, wearable devices, industrial machinery, and 

drones. See Jill C. Gallagher & Michael E. DeVine, Cong. Research Serv., R45485, FifthGeneration (5G) Telecommunications Technologies: Issues for Congress 2–6 (2019). To handle 

all the wireless data transmitted by these new technologies, carriers must greatly increase the 

number of cell sites nationwide. Verizon, for example, recently estimated that upgrading the 

nation’s wireless infrastructure to prepare for 5G will require “100 times more antenna locations 

than currently exist,” and AT&T projected “that providers will deploy hundreds of thousands of 

wireless facilities in the next few years alone—equal to or more than the number providers have 

deployed in total over the last few decades.” In the Matter of Accelerating Wireless Broadband 

Deployment by Removing Barriers to Infrastructure Inv., F.C.C. No. 18-133, 2018 WL 4678555, 

at *17 (Sept. 27, 2018). 

Against the backdrop of this new era of connected devices, § 2703(d) of the SCA—a 

provision first drafted 25 years ago—permits law enforcement to obtain certain records of a 
No. 14-1572 United States v. Carpenter Page 3

person’s wireless communications whenever the government “offers specific and articulable 

facts showing that there are reasonable grounds to believe” the records sought “are relevant and 

material to an ongoing criminal investigation.” See Communications Assistance for Law 

Enforcement Act, Pub. L. No. 103-414, 108 Stat. 4279, 4292 (1994). Unlike other provisions of 

the SCA, the court-ordered production mechanism in § 2703(d) does not require law 

enforcement to get a warrant before acquiring these records. Compare 18 U.S.C. § 2703(d) with 

id. § 2703(a), (c)(1)(A). In this case, the Government collected Carpenter’s CSLI under 

§ 2703(d); it did not obtain a warrant. 

B. Factual and Procedural History

Because we and the Supreme Court summarized the facts of this case in prior decisions, 

see Carpenter II, 138 S. Ct. at 2211–13; United States v. Carpenter (Carpenter I), 819 F.3d 880, 

884–85 (6th Cir. 2016), we focus on the information most relevant to the analysis on remand. 

First, a housekeeping matter: Carpenter I addressed the consolidated appeals of both Carpenter 

and a codefendant, Timothy Michael Sanders, see 819 F.3d at 884, but only Carpenter sought 

Supreme Court review. Carpenter limited his petition for certiorari to the question of whether 

the Fourth Amendment permits the warrantless acquisition of CSLI, see Petition for Writ of 

Certiorari, Carpenter II, 138 S. Ct. 2206 (No. 16-402), and did not include the other grounds for 

appeal that he raised (and we rejected) in Carpenter I, see 819 F.3d at 890–93. We adopt 

Carpenter I’s treatment of those issues not considered in Carpenter II. Our task here is only to 

apply the Supreme Court’s Fourth Amendment analysis to Carpenter’s case. 

A federal jury convicted Carpenter of robbery and gun charges after he and others 

committed a string of robberies in Michigan and Ohio between 2010 and 2012. During its 

investigation, the Government sought court orders under § 2703(d) for Carpenter’s CSLI. In 

response to the Government’s applications, two magistrate judges ordered Carpenter’s wireless 

carriers to provide “the locations of cell/site sector (physical addresses) for the target telephones 

at call origination and at call termination for incoming and outgoing calls.” Carpenter II 

described the scope of the CSLI turned over by Carpenter’s carriers: 
No. 14-1572 United States v. Carpenter Page 4

The first order sought 152 days of cell-site records from MetroPCS, which 

produced records spanning 127 days. The second order requested seven days of 

CSLI from Sprint, which produced two days of records covering the period when

Carpenter’s phone was “roaming” in northeastern Ohio. Altogether the 

Government obtained 12,898 location points cataloging Carpenter’s

movements—an average of 101 data points per day.

138 S. Ct. at 2212. Carpenter joined Sanders’s motion in limine to suppress the cell phone data, 

which the district court denied. 

At trial, the Government used Carpenter’s CSLI to create a record of his physical 

proximity to many of the alleged robberies:

With the cell-site data provided by Carpenter’s and Sanders’s wireless carriers, 

[FBI agent Christopher] Hess created maps showing that Carpenter’s and 

Sanders’s phones were within a half-mile to two miles of the location of each of 

the robberies around the time the robberies happened. Hess used MetroPCS calldetail records, for example, to show that Carpenter was within that proximity of a 

Detroit Radio Shack that was robbed around 10:35 a.m. on December 13, 2010. 

Specifically, MetroPCS records showed that at 10:24 a.m. Carpenter’s phone 

received a call that lasted about four minutes. At the start and end of the call, 

Carpenter’s phone drew its signal from MetroPCS tower 173, sectors 1 and 2, 

located southwest of the store and whose signals point north-northeast. After the 

robbery, Carpenter placed an eight-minute call originating at tower 145, sector 3, 

located northeast of the store, its signal pointing southwest; when the call ended, 

Carpenter’s phone was receiving its signal from tower 164, sector 1, alongside 

Interstate 94, north of the Radio Shack. Hess provided similar analysis 

concerning the locations of Carpenter’s and Sanders’s phones at the time of a 

December 18, 2010 robbery in Detroit; a March 4, 2011 robbery in Warren, Ohio; 

and an April 5, 2011 robbery in Detroit. 

Carpenter I, 819 F.3d at 885. The Government emphasized the importance of Carpenter’s CSLI 

during its closing argument, saying: “Then there’s another overlay of corroboration and that is 

the phone data tracking. Little Tim[othy Carpenter]’s phone just happened to be right where the 

first robbery was at the exact time of the robbery, the exact sector.” 

A jury convicted Carpenter of Hobbs Act robbery and related gun charges in violation of 

18 U.S.C. §§ 924(c) and 1951(a). The district court sentenced him to more than 100 years in 

prison, and he appealed. We affirmed in a divided opinion, with the majority rejecting 

Carpenter’s claim that the Government’s collection of his CSLI was a warrantless search in 
No. 14-1572 United States v. Carpenter Page 5

violation of the Fourth Amendment. Carpenter filed a petition for certiorari, which the Supreme 

Court granted. 

C. Carpenter II

Carpenter II begins by situating the Government’s acquisition of Carpenter’s CSLI at 

“the intersection of two lines” of Fourth Amendment precedent. 138 S. Ct. at 2214–15. The first 

line “addresses a person’s expectation of privacy in his physical location and movements,” while 

the second holds that “a person has no legitimate expectation of privacy in information he 

voluntarily turns over to third parties.” See id. at 2215–16 (citation omitted); see also Carpenter 

I, 819 F.3d at 895 (Stranch, J., concurring in the judgment).

As for the first line of precedent, Carpenter II explained that “when the Government 

tracks the location of a cell phone it achieves near perfect surveillance, as if it had attached an 

ankle monitor to the phone’s user.” 138 S. Ct. at 2218. Key to the Court’s reasoning was the 

inability of CSLI to distinguish between public and private life: because a cell phone “faithfully 

follows its owner beyond public thoroughfares and into private residences, doctor’s offices, 

political headquarters, and other potentially revealing locales,” any collection of CSLI risks 

opening “an intimate window into a person’s life, revealing not only his particular movements, 

but through them his ‘familial, political, professional, religious, and sexual associations.’” Id. at 

2217 (quoting United States v. Jones, 565 U.S. 400, 415 (2012) (Sotomayor, J., concurring)). 

The Court found that Carpenter had a “reasonable expectation of privacy in the whole of his 

physical movements” as recorded by his CSLI. Id. at 2219. 

Under the second line of cases, the Court held that the third-party doctrine did not shield 

the Government’s collection of CSLI from Fourth Amendment safeguards. That doctrine 

originated decades ago, when “few could have imagined a society in which a phone goes 

wherever its owner goes[.]” Id. at 2217. Nor could prior courts have anticipated the “depth, 

breadth, and comprehensive reach” of the CSLI used by law enforcement today. Id. at 2223. 

Because cell phone owners do not, in any “meaningful sense,” choose to turn over such a 

thorough record of their public and private lives, the Court found that the acquisition of 
No. 14-1572 United States v. Carpenter Page 6

Carpenter’s CSLI was a Fourth Amendment search regardless of whether the Government 

obtained the data from a third party. Id. at 2220. 

With the Supreme Court’s guidance in mind, we reevaluate whether the district court 

properly permitted the Government to introduce Carpenter’s CSLI at trial.

II. ANALYSIS

“When reviewing the denial of a motion to suppress, we will set aside the district court’s 

factual findings only if they are clearly erroneous, but will review de novo the court’s 

conclusions of law.” United States v. Lee, 793 F.3d 680, 684 (6th Cir. 2015). The Supreme 

Court’s decision in Carpenter II leaves no doubt that the Government’s collection of Carpenter’s 

CSLI was a search under the Fourth Amendment. The Government needed a warrant to obtain 

that information, and the district court erred in concluding otherwise. As Carpenter II explained: 

“Before compelling a wireless carrier to turn over a subscriber’s CSLI, the Government’s 

obligation is a familiar one—get a warrant.” 138 S. Ct. at 2221.

Although the Government should have obtained a warrant in this case, we may 

nevertheless affirm the district court’s decision if the Government acquired Carpenter’s CSLI in 

good faith reliance on the SCA. “Though evidence obtained in violation of the Fourth 

Amendment is generally excluded, the Supreme Court has held that the exclusionary rule ‘should 

be modified so as not to bar the admission of evidence seized in reasonable, good faith reliance 

on a search warrant that is subsequently held to be defective.’” United States v. Frazier, 423 

F.3d 526, 533 (6th Cir. 2005) (quoting United States v. Leon, 468 U.S. 897, 905 (1984)). In 

Illinois v. Krull, the Court extended Leon’s good faith exception to evidence obtained in 

reasonable reliance on a statute that is later declared unconstitutional, reasoning “that the greatest 

deterrent to the enactment of unconstitutional statutes by a legislature is the power of the courts 

to invalidate such statutes.” 480 U.S. 340, 352 (1987); see also id. at 349 (“The application of 

the exclusionary rule to suppress evidence obtained by an officer acting in objectively reasonable 

reliance on a statute would have as little deterrent effect on the officer’s actions as would the 

exclusion of evidence when an officer acts in objectively reasonable reliance on a warrant.”). 
No. 14-1572 United States v. Carpenter Page 7

That Carpenter II did not invalidate § 2703(d) whole cloth does not meaningfully 

distinguish this case from Krull. What matters is whether it was objectively reasonable for the 

officers to rely on the statute at the time of the search. See id. Here, it was not unreasonable for 

the FBI agents who acquired Carpenter’s CSLI to rely on § 2703(d). The SCA contemplates the 

Fourth Amendment’s protections by specifying some instances where warrants are necessary, 

see 18 U.S.C. § 2703(a), (c)(1)(A), so one can understand why the agents might have believed—

wrongly, it turns out—that a warrant was not required to obtain CSLI under § 2703(d). And it 

was not just these officers who believed that § 2703(d) empowered the Government to acquire 

CSLI without a warrant. Two magistrate judges issued court orders granting the Government’s 

request to compel the production of Carpenter’s CSLI. At the time these requests were granted, 

this circuit had already considered reliance on § 2703(d) to be reasonable. See United States v. 

Warshak, 631 F.3d 266, 288–89 (6th Cir. 2010) (finding that government agents relied on

§ 2703(d) in good faith when compelling a defendant’s internet service provider to produce the 

defendant’s emails).1 And despite Carpenter’s arguments to the contrary, nothing in the record 

suggests that the FBI agents who obtained his CSLI engaged in intentional misconduct. 

Carpenter II confirmed that the SCA does not immunize a government officer’s 

collection of CSLI from the safeguards of the Fourth Amendment. Moving forward, traditional 

Fourth Amendment principles will replace reflexive or mechanical use of § 2703(d). The 

government must either get a warrant or rely on a recognized exception to the warrant 

requirement. 

III. CONCLUSION

Carpenter II teaches that, to avoid “embarrass[ing] the future,” courts must carefully and 

incrementally adapt their Fourth Amendment jurisprudence to advancements in the digital era. 

138 S. Ct. at 2220 (citation omitted). The Government’s acquisition of Carpenter’s CSLI 

violated the Fourth Amendment. The district court nevertheless properly denied suppression 

 

1Although Warshak announced a prospective rule barring the warrantless search of a suspect’s 

private emails under § 2703(d), the court did not address any other circumstances where reliance on 

§ 2703(d) might be unreasonable. The decision in Warshak therefore would not have alerted the agents in 

Carpenter’s case to the unconstitutionality of seeking the CSLI at issue here.
No. 14-1572 United States v. Carpenter Page 8

because the FBI agents relied in good faith on the SCA when they obtained the data. We 

therefore AFFIRM.