Use of a Stingray is a “search” and requires a warrant. The court notes the differing approaches of the courts, but this court has already weighed in in favor of the citizen. “Accordingly, the court determines that a warrant was not required to deploy the Stingrays to locate Ellis’s cell phone under the exigent circumstances that existed the morning of January 22, 2013. Ellis’s motion to suppress evidence obtained from use of the Stingrays is therefore DENIED.” United States v. Ellis, 2017 U.S. Dist. LEXIS 136217 (N.D. Cal. Aug. 24, 2017). On the privacy question:
On a related issue, several judges in this district have recognized a right to privacy in historical cell site location information (“CSLI”) that is collected by cellular service providers. CSLI is generated by the radio signals emanated by a cell phone to the closest cell tower in the cellular service network, as described more fully by Judge Koh in In re Application for Telephone Information Needed for a Criminal Investigation, 119 F. Supp. 3d 1011, 1013-15 (N.D. Cal. 2015), No. 15-xr-90304 HRL (LHK), doc. no. 30, appeal dismissed (Feb. 5, 2016). “The resulting CSLI includes the precise location of the cell tower and cell site serving the subject cell phone during each voice call, text message or data connection,” and may be generated even without the user’s interaction with the cell phone. Id. at 1014 (citations omitted).
Judge Illston addressed the privacy interests in such information in United States v. Cooper, 2015 U.S. Dist. LEXIS 25935, 2015 WL 881578 (N.D. Cal., Mar. 2, 2015), No. 13-cr-693 SI, doc. no. 117. There, the defendant moved to suppress evidence obtained from collecting historical and prospective, or real-time, cell site location information without a warrant. Judge Illston recognized that cell phone users have a reasonable expectation of privacy in their physical location as conveyed by historical CSLI that is protected by the Fourth Amendment. 2015 U.S. Dist. LEXIS 25935, [WL] at *6-11 (citing United States v. Davis, 754 F.3d 1205, 1215 (11th Cir.), vacated, 573 Fed. Appx. 925 (11th Cir. 2014), and reheard en banc in part, 785 F.3d 498 (11th Cir. 2015)). Judge Illston did not reach the Fourth Amendment issue with respect to prospective CSLI, but held, as further discussed below at pp. 16-17, that by application of the Communications Assistance of Law Enforcement Act (“CALEA”), 47 U.S.C. § 1002(a)(2), the pen register statute did not authorize access to call-identifying information from telecommunications carriers that may disclose the subscriber’s physical location, and that a showing of probable cause was required to obtain prospective cell site data. 2015 U.S. Dist. LEXIS 25935, [WL] at *3-6. Although the government had not obtained a warrant, the court denied the motions to suppress upon finding that the agents relied in good faith on the magistrate judge’s order authorizing a pen register. 2015 U.S. Dist. LEXIS 25935, [WL] at *11-12.
Judge Koh also held that cell phone users have a reasonable expectation of privacy in historical CSLI, requiring a warrant to obtain such information absent case-specific exceptions. In re Appl. for Tel. Info., 119 F. Supp. 3d at 1025-26. There, the government submitted an application to Magistrate Judge Lloyd for an order authorizing it to obtain both historical and prospective CSLI for target cell phones pursuant to the Stored Communications Act (“SCA”), 18 U.S.C. § 2703(d), which sets forth a “specific and articulable facts” standard that requires a lesser showing than probable cause. Following Cooper, Magistrate Judge Lloyd denied the application and required the government to obtain a search warrant to obtain cell site information, whether historical or prospective. No. 15-xr-90304 HRL (LHK), doc. no. 2.
The government appealed Magistrate Judge Lloyd’s denial with respect to the application for historical CSLI. In affirming that decision, Judge Koh articulated several Fourth Amendment principles based on Supreme Court precedent: …
. . .
The court adopts Judge Koh’s reasoning in In re Application for Telephone Information, 119 F. Supp. 3d at 1026, to hold that cell phone users have an expectation of privacy in their cell phone location in real time and that society is prepared to recognize that expectation as reasonable. While Judge Koh limited her analysis to the privacy interest in historical CSLI, the court determines that cell phone users have an even stronger privacy interest in real time location information associated with their cell phones, which act as a close proxy to one’s actual physical location because most cell phone users keep their phones on their person or within reach, as the Supreme Court recognized in Riley. In light of the persuasive authority of Lambis, and the reasoning of my learned colleagues on this court recognizing a privacy interest in historical cell site location information, the court holds that Ellis had a reasonable expectation of privacy in his real-time cell phone location, and that use of the Stingray devices to locate his cell phone amounted to a search requiring a warrant, absent an exception to the warrant requirement.
d. Privacy Interest in One’s Public Movements
Ellis further argues that because a Stingray can track an individual’s location by locating his cell phone with an accuracy of about two meters, its use infringed upon his reasonable expectation of privacy in one’s public movements, as considered by Justice Sotomayor in her concurring opinion in Jones: “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. … I would take these attributes of GPS monitoring into account when considering the existence of a reasonable societal expectation of privacy in the sum of one’s public movements.” Doc. no. 304 at 16 (citing Jones, 565 U.S. at 415-16 (Sotomayor, J., concurring)). The Court in Jones did not reach the question whether the Fourth Amendment protects a privacy interest in one’s public movements, and even Justice Sotomayor did not attempt to resolve these “difficult questions” because “the Government’s physical intrusion on Jones’ Jeep supplies a narrower basis for decision.” Id. at 418. Accordingly, Ellis fails to establish that a reasonable expectation of privacy in one’s public movements that is protected under the Fourth Amendment has been recognized by any court.