Warrantless use of a cell site simulator to capture cell phone calls violates the Fourth Amendment. That information was used to get a search warrant for CSLI. State v. Sylvestre, 2018 Fla. App. LEXIS 12671 (Fla. 4th DCA Sep. 6, 2018):
Generally, a cell-site simulator “transform[s] a cell phone into a real time tracking device.” Staff of Comm. on the Oversight and Government Reform, 114th Cong., Law Enforcement Use of Cell-Site Simulation Technologies: Privacy Concerns and Recommendations (Dec. 19, 2016), https://oversight.house.gov/wp-content/uploads/2016/12/THE-FINAL-bipartisan-cell-site-simulator-report.pdf. It “‘tricks’ nearby cell phones into thinking that it’s a cell tower, thereby causing nearby cell phones to send signals to the device, which allows the operator of the device to locate the phone being sought.” United States v. Artis, 315 F. Supp. 3d 1142, 2018 WL 3241400, at *2 (N.D. Cal. 2018) (citations omitted); see also Lambis, 197 F. Supp. 3d at 609.
Thus, cell-site simulators present significant privacy concerns. At the same time, they “are invaluable law enforcement tools that locate or identify mobile devices during active criminal investigations.” U.S. Dep’t of Homeland Security, Department Policy Regarding the Use of Cell-Site Simulator Technology 1 (Oct. 19, 2015), https://www.dhs.gov/sites/ default/files/publications/Department%20Policy%20Regarding%20the% 20Use%20of%20Cell-Site%20Simulator%20Technology.pdf.
These competing interests are not novel. Technological advancement often collides with the Fourth Amendment. When balancing these interests, we must “ensure that the ‘progress of science’ does not erode Fourth Amendment protections.” Carpenter, 138 S. Ct. at 2223 (quoting Olmstead v. United States, 277 U.S. 438, 473-74, 48 S. Ct. 564, 72 L. Ed. 944 (1928) (Brandeis, J., dissenting)). To do so, the Supreme Court appears to “adjust legal rules to restore the preexisting balance of police power” as technology advances. Orin S. Kerr, An Equilibrium-Adjustment Theory of the Fourth Amendment, 125 HARV. L. REV. 476, 482 (2011).
. . .
Following Riley, the Florida Supreme Court held that a defendant
had a subjective expectation of privacy in the location signals transmitted solely to enable the private and personal use of his cell phone, even on public roads, and that he did not voluntarily convey that information to the service provider for any purpose other than for its intended purpose.
Tracey, 152 So. 3d at 525.
And recently, the United States Supreme Court recognized the “deeply revealing nature of CSLI, its depth, breadth, and comprehensive reach, and the inescapable and automatic nature of its collection[.]” Carpenter, 138 S. Ct. at 2223. The Supreme Court stated:
[T]he progress of science has afforded law enforcement a powerful new tool to carry out its important responsibilities. At the same time, this tool risks Government encroachment of the sort the Framers, “after consulting the lessons of history,” drafted the Fourth Amendment to prevent.
Id. (quoting United States v. Di Re, 332 U.S. 581, 595, 68 S. Ct. 222, 92 L. Ed. 210 (1948)). Thus, the Supreme Court applied Professor Kerr’s equilibrium-adjustment theory and held that the government “must generally obtain a warrant supported by probable cause before acquiring such records.” Id. at 2221.
Together these cases hold that, without a warrant, the government cannot: use technology to view information not visible to the naked eye, attach a device to property to monitor your location, search a cell phone in your possession without a warrant, or obtain real-time location information from the cell carrier.
With a cell-site simulator, the government does more than obtain data held by a third party. The government surreptitiously intercepts a signal that the user intended to send to a carrier’s cell-site tower or independently pings a cell phone to determine its location. Not only that, a cell-site simulator also intercepts the data of other cell phones in the area, including the phones of people not being investigated.
If a warrant is required for the government to obtain historical cell-site information voluntarily maintained and in the possession of a third party, see Carpenter, 138 S. Ct. at 2221, we can discern no reason why a warrant would not be required for the more invasive use of a cell-site simulator. See, e.g., United States v. Ellis, 270 F. Supp. 3d 1134, 1145 (N.D. Cal. 2017). This is especially true when the cell phone is in a private residence, Karo, 468 U.S. at 718, or other private locations “beyond public thoroughfares” including “doctor’s offices, political headquarters, and other potentially revealing locales.” Carpenter, 138 S. Ct. at 2218.
Accord: Ferrari v. State, 2018 Fla. App. LEXIS 12672 (Fla. 4th DCA Sep. 6, 2018).