by Nelson S. Ebaugh, Nelson S. Ebaugh, P.C.

The law is always one step behind technology. In connection with cell site location information (“CSLI”), the law is starting to catch up.  However, there are still many unanswered questions.  For instance, how long can the government track a person’s cell phone before it becomes a Fourth Amendment search?

In sum, CSLI is a time-stamped record identifying which antenna on which cell tower provided a connection for a cell phone.  A smartphone connects to a cell tower several times a minute, even when the owner is not using the device.  Consequently, cell phones and smartphones leave a breadcrumb trail of CSLI identifying almost everywhere they have been.  Such information can confirm a suspect’s presence at the scene of the crime. It can also help law enforcement locate a suspect in real time. To be sure, use of CSLI in this manner also raises significant privacy concerns. Accordingly, the U.S. Supreme Court and the Texas Court of Criminal Appeals (“TCCA”) have each taken steps to rein in law enforcement’s access to such information without a warrant.

In Carpenter v. United States, 138 S.Ct. 2206 (2018), the U.S. Supreme Court held that law enforcement officers must obtain a warrant in order to obtain seven days or more of historical CSLI. In Sims v. State, 569 S.W.3d 634 (Tex. Crim. App. 2019), the TCCA applied Carpenter’s reasoning to extend the warrant requirement to real-time CSLI, too. Both courts recognize that long term surveillance conducted through CSLI entails a Fourth Amendment search. Simply put, long term tracking via CSLI “provides 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.’”[i]  Accordingly, law enforcement ordinarily must obtain a warrant to seize such information.

In Texas, long term surveillance through either historical or real-time CSLI infringes on a person’s expectation of privacy. However, it is unclear whether such infringement occurs after only a few hours of CSLI surveillance or if infringement does not occur until after several days of CSLI surveillance.  Although Texas courts have not provided much guidance on this issue, courts in other states have begun to tackle the issue. Decisions from other states may indicate how a Texas court would decide what length or method of CSLI surveillance infringes on a person’s legitimate expectation of privacy.

In short, this article discusses guidance from the U.S. Supreme Court and from the TCCA on how long the government may track a person’s cell phone before it becomes a Fourth Amendment search.  Then it considers recent cases from other states that have either adopted or rejected the “short-term” CSLI exception to the warrant requirement.

Historical CSLI: long term v. short term

In Carpenter, the U.S. Supreme Court decided “how to apply the Fourth Amendment to a new phenomenon: the ability to chronicle a person’s past movements through the record of his cell phone signals.”[ii]  A majority agreed that even though CSLI is kept by a third-party wireless carrier, “an individual maintains a legitimate expectation of privacy in the record of his physical movements as captured through CSLI.”[iii]  In other words, because cell phones are “indispensable to participation in modern society” and cell phone location is “not truly ‘shared’ as one normally understands the term,”[iv] a person has a reasonable expectation of privacy in CSLI generated from the use of his mobile device even if it is entrusted with a wireless carrier, i.e., a third party.

After Carpenter, courts have struggled to determine how long the government may track a person’s historical CSLI before it violates a person’s reasonable expectation of privacy in those records.  In such cases, each court makes at least a passing reference to the Supreme Court’s holding that “accessing seven days of CSLI constitutes a Fourth Amendment search.”[v]  However, what the Supreme Court meant by this holding is up for debate.

For instance, in State v. Snowden, 2019-Ohio-3006, — N.E.3d —- (2d Dist.), the Ohio Second District Court of Appeals rejected “the State’s argument that Carpenter explicitly limited its holding to the collection of seven days or more of CSLI.”[vi]  According to the Snowden court, the following language used by the U.S. Supreme Court in Carpenter “arguably suggests just the opposite . . . . :” [vii]

***[W]e need not decide whether there is a limited period for which the Government may obtain an individual’s historical CSLI free from Fourth Amendment scrutiny, and if so, how long that period might be. It is sufficient for our purposes today to hold that accessing seven days of CSLI constitutes a Fourth Amendment search.[viii]

Based upon this comment in Carpenter, the Ohio Second District Court of Appeals held as follows:

[A]lthough the State’s request for CSLI was limited to a two-day period, there is no rationale that such a request is not a ‘search.’  Before compelling a wireless carrier to turn over a subscriber’s CSLI, the State’s obligation is a familiar one – obtain a warrant. This is logically true whether it is one day, two days, three days, or seven days or more of data obtained.[ix]

However, in People v. Edwards, 63 Misc.3d 827, 97 N.Y.S.3d 418 (N.Y. Sup. Ct. 2019), the Bronx County Supreme Court took the converse position when law enforcement in that case likewise sought CSLI for a two-day period.  In Edwards, the court held that obtaining CSLI over a period of only two days was not a Fourth Amendment search under “Carpenter‘s apparent ‘short-term’ CSLI exception.”[x]  According to the court, “the Carpenter court . . . expressly declined to say whether a Fourth Amendment ‘search’ takes place where the government obtains CSLI data for a limited period of seven days or less.”[xi]  From this observation, the court proceeded to elaborate on “Carpenter‘s apparent ‘short-term’ CSLI exception.”

The Supreme Court had good reason to expressly exempt short-term CSLI data from its Carpenter decision. Gathering long-term CSLI data is much more clearly an invasion of a cellular telephone holder’s legitimate expectation of privacy; it is, in a sense, the modern day electronic equivalent of sending a government spy out to follow the defendant both day and night, wherever he or she goes, in public or in private.

By way of contrast, in this Court’s view, short-term CSLI data that is carefully targeted to a specific time in order to determine whether defendant was present at the scene of a crime that was committed in a public place is not a search, and is therefore not subject to Fourth Amendment warrant requirements.

The difference between long-term and short-term CSLI data is stark: long-term data can be likened to filming a person’s entire life for weeks, or months, or even years; short-term CSLI data is like taking a single snapshot of that person on the street.[xii]

After expounding on “Carpenter‘s apparent ‘short-term’ CSLI exception,” the court denied the defendant’s motion to suppress two days of historical CSLI.[xiii]

In sum, there is already a difference of opinion as to whether obtaining two days of historical CSLI constitutes a Fourth Amendment search.  Courts in Texas and across the nation must now decide whether there is “short-term CSLI exception” that would exempt a request for a two-day period of historical CSLI.

Real-time CSLI: long term v. short term

In Carpenter, the Supreme Court stated: “Our decision today is a narrow one. We do not express a view on matters not before us: real-time CSLI . . . .”[xiv]  Less than a year later, however, the TCCA held that Carpenter’s reasoning applies not only to historical CSLI but to real-time CSLI, too.

In Sims, the TCCA observed that “unlike historical CSLI, which is maintained by cell phone service providers for business purposes, but which are occasionally accessed by law enforcement, real-time CSLI records are generated solely at the behest of law enforcement.”[xv]  In any event, the TCCA concluded that “[t]he nature of real-time CSLI records are not meaningfully different [from historical CSLI records]: Real time CSLI records show location information, which is catalogued through no action of the subscriber.”[xvi]  Under the circumstances of the case, however, the TCCA held that tracking defendant Sims by CSLI for less than three hours by pinging his phone only occasionally was not a Fourth Amendment search.

In reaching the conclusion that defendant Sims “did not have a legitimate expectation of privacy in his physical movements or his location as reflected in the less than three hours of real-time CSLI records accessed by police by pinging his phone less than five times,”[xvii] the TCCA held as follows:

Whether a particular government action constitutes a “search” or “seizure” does not turn on the content of the CSLI records; it turns on whether the government searched or seized “enough” information that it violated a legitimate expectation of privacy. There is no bright-line rule for determining how long police must track a person’s cell phone in real time before it violates a person’s legitimate expectation of privacy in those records.  Whether a person has a recognized expectation of privacy in real-time CSLI records must be decided on a case-by-case basis.[xviii]

In other words, the TCCA employed an analysis like the “‘short-term’ CSLI exception” utilized by the Bronx County Supreme Court in Edwards.  In conclusion, the TCCA held that “[f]ive justices on the United States Supreme Court have supported the idea that longer-term surveillance might infringe on a person’s legitimate expectation of privacy if the location records reveal the ‘privacies of [his] life,’ but this is not that case.”[xix]

The TCCA is not the only court to conclude that use of real-time CSLI to conduct surveillance over a short period of time does not require a warrant.  For instance, in People v. Bui, No. H044430, 2019 WL 1325260 (Cal. App. 6th Dist. 2019), the California Sixth District Court of Appeal “conclude[d] that defendant did not have a legitimate expectation of privacy, i.e., one that society is prepared to recognize as reasonable, in the real-time CSLI that was accessed by law enforcement for a brief period—approximately an hour and a half—as an aid in visually locating him on public streets and arresting him pursuant to a warrant.”[xx]  However, the Bui court stressed the “very limited nature of [its] conclusion,” emphasizing that it had “not decided that obtaining real-time CSLI is never a search or that real-time CSLI can be used to track a cell phone, and presumably its user, into a private home or business.”[xxi]

In connection with real-time CSLI surveillance, one other issue merits attention.  When the police are investigating in real time, they can ask a cellular service provider to “ping” a cell phone to “actively induce it to divulge its identifying information for their own investigatory purposes.”[xxii]

In Commonwealth v. Almonor, 482 Mass. 35, 120 N.E.3d 1183 (2019), the Supreme Judicial Court of Massachusetts considered “whether police action causing an individual’s cell phone to reveal its real-time location constitutes a search in the constitutional sense under either the Fourth Amendment or art. 14” of the Massachusetts Declaration of Rights.[xxiii]  Significantly, the court held that pinging a cell phone, even once, constituted a search under art. 14 of the Massachusetts Declaration of Rights, triggering the warrant requirement.  The court reasoned as follows:

The intrusive nature of police action that causes an individual’s cell phone to transmit its real-time location raises distinct privacy concerns. When the police ping a cell phone, as they did in this case, they compel it to emit a signal, and create a transmission identifying its real-time location information. Matter of an Application of the U.S.A. for an Order Authorizing Disclosure of Location Info. of a Specified Wireless Tel., 849 F.Supp.2d 526, 534 (D. Md. 2011) (Matter of an Application) (describing that ping of cell phone “send[s] a signal directing the built-in satellite receiver in a particular [cell phone] to calculate its location and transmit the location data back to the service provider”). This action and transmission is initiated and effectively controlled by the police, and is done without any express or implied authorization or other involvement by the individual cell phone user.  See id. (noting that cell phone ping is “undetectable to the [cell phone] user”).  Without police direction, such data would also not otherwise be collected and retained by the service provider. See id. (noting that service providers “typically do not maintain records of the GPS coordinates of [cell phones] operating on their network”).  Accordingly, in pinging a cell phone, the police “actively induce[ ] [it] to divulge its identifying information” for their own investigatory purposes.  Jones v. United States, 168 A.3d 703, 713 (D.C. 2017).

We confidently conclude that such police action implicates reasonable expectations of privacy.  Indeed, society reasonably expects that the police will not be able to secretly manipulate our personal cell phones for any purpose, let alone for the purpose of transmitting our personal location data.[xxiv]

To be sure, the Almonor court concluded that a ping is a search under art. 14 of the Massachusetts Declaration of Rights.  That is, it did not hold that a ping qualified as a search under the Fourth Amendment to the United States Constitution, too.[xxv]  In any event, the Almonor court’s analysis is persuasive and can be invoked to argue that when the government pings a cell phone, even once, such activity entails a search under the Fourth Amendment.  In fact, in Reed v. Commonwealth, 2018-CA-001574-MR, 2020 WL 594084, — S.W.3d —- (Ky. App. 2020), the Kentucky Court of Appeals recently adopted Almonor’s reasoning to hold that “because pinging a cell phone enables the police almost instantaneously to track individuals far beyond the public thoroughfare into areas where they would have a reasonable, legitimate expectation of privacy, we conclude that a warrant is required to acquire real-time CSLI.”[xxvi]

One can only wonder if the outcomes in Sims and Bui would have been different if the defendant in each of those cases had argued, as in Almonor and Reed, that even one ping to determine a suspects whereabouts is “a degree of intrusion that a reasonable person would not anticipate[.]”[xxvii]  In Sims and Bui, law enforcement requested a cell service provider to ping the defendant’s phone, too.[xxviii]  However, the defendants in Sims and Bui each apparently declined to make the argument that pinging a cell phone, alone, is a degree of intrusion that a reasonable person would not anticipate.  Accordingly, the courts in those two cases largely focused on the length of the real time surveillance.  In Texas, it may behoove a defendant to argue that the intrusiveness of a ping itself, regardless of the length of the real-time surveillance, entails a Fourth Amendment search.

Conclusion

It has been less than two years since the U.S. Supreme Court issued its seminal decision in Carpenter.  In that brief period, courts have been all over the map on the issue of whether a “short-term” exception exists for either historical CSLI or real-time CSLI.  In Texas, only one thing is certain: There is a “short-term” CSLI exception applicable to real-time monitoring.  However, a defendant can make the argument that the intrusiveness of a ping itself, regardless of the length of the real-time surveillance, entails a Fourth Amendment search.

[i] Carpenter v. United States, 138 S.Ct. 2206, 2217 (2018).

[ii] Id. at 2216.

[iii] Id. at 2220.

[iv] Id.

[v] Id. at 2217 n. 3.

[vi] State v. Snowden, 2019-Ohio-3006, — N.E.3d —-, ¶ 32 (2d Dist.).

[vii] Id.

[viii] Id. (citing Carpenter at 2272, fn. 3).

[ix] Id. at ¶ 33 (citation omitted).

[x] People v. Edwards, 63 Misc.3d 827, 833, 97 N.Y.S.3d 418, 422 (N.Y. Sup. Ct. 2019).

[xi] Edwards, 63 Misc.3d at 831, 97 N.Y.S.3d 421 (citing Carpenter, 138 S.Ct. at 2217, note 3).

[xii] Edwards, 63 Misc.3d at 832, 97 N.Y.S.3d 421-22 (italics in original) (citations and parentheticals omitted).

[xiii] Edwards, 63 Misc.3d at 833, 97 N.Y.S.3d 422 (citations and parentheticals omitted).

[xiv] Carpenter, 138 S.Ct. at 2220.

[xv] Sims v. State, 569 S.W.3d 634, 645 n. 15 (Tex. Crim. App. 2019) (citation omitted).

[xvi] Id. (citation omitted).

[xvii] Id. at 646.

[xviii] Id. at 645-46 (footnote omitted).

[xix] Id. at 646 (quoting Carpenter, 138 S.Ct. at 221.).

[xx] People v. Bui, No. H044430, 2019 WL 1325260, at *21 (Cal. App. 6th Dist. 2019).

[xxi] Id.

[xxii] Commonwealth v. Almonor, 482 Mass. 35, 44, 120 N.E.3d 1183, 1193 (2019) (cleaned up).

[xxiii] Almonor, 482 Mass. at 36-37, 120 N.E.3d at 1188.

[xxiv] Almonor, 482 Mass. at 43-44, 120 N.E.3d at 1192 (footnotes omitted).

[xxv] Almonor, 482 Mass. at 42 n. 9, 120 N.E.3d at 1192 n. 9.

[xxvi] Reed v. Commonwealth, 2018-CA-001574-MR, 2020 WL 594084, at *5, — S.W.3d —- (Ky. App. 2020).

[xxvii] Id. (quoting Commonwealth v. Almonor, 482 Mass. 35, 120 N.E.3d 1183, 1195 (2019) (quoting State v. Earls, 214 N.J. 564, 70 A.3d 630, 642 (2013))).

[xxviii] Sims, 569 S.W.3d at 636 (defendant “filed a pretrial motion to suppress evidence of real-time location information used to track his cell phone by ‘pinging’ it without a warrant”); Bui, 2019 WL 1325260, at *12 (using “the process of ‘pinging’ a cell phone with the assistance of the service provider” to locate the defendant).