Eliminating the Chase: Fourth Amendment Implications of Warrantless Use of Cell-Site Simulators to Search for Criminal Offenders

Eliminating the Chase: Fourth Amendment Implications of Warrantless Use of Cell-Site Simulators to Search for Criminal Offenders

Katie A. Monin, Staff Editor[1]

In 2008, the Executive Office for United States Attorneys produced several documents in response to a request for records under the Freedom of Information Act.[2] The documents revealed that the U.S. Government had access to, and had been utilizing, cell-site simulators as a means of electronic surveillance.[3] Before this revelation, government use of cell-site simulators was largely unknown to the public;[4] due, in part, to the fact that the FBI would require law enforcement agencies to sign non-disclosure agreements upon purchase of cell-site simulators.[5] Use of cell-site simulators can have significant Fourth Amendment implications since the devices have the capability to search for and locate an individual by tracking the location of his or her cell phone.[6] Despite these Constitutional implications, courts have only recently begun confronting issues regarding what limits the Fourth Amendment[7] places on government use of cell-site simulators.[8] Until the Supreme Court confronts the issue, warrantless use of cell-site simulators during the course of an investigation is likely to continue.

“Cell-site simulators” are portable devices which have the capability not only to “masquerade” as a cell-tower, but can also intercept content from cellular devices within the vicinity.[9] When the cell-site simulator is activated, it emits signals within a particular area.[10] In response to these signals, a cellular device in proximity of the simulator “identifies the simulator as the most attractive cell tower in the area and thus transmits signals to the simulator that identify the device in that same way that they would in a networked tower.”[11] A cell-site simulator does not function like a GPS locator of a cell phone, but it does provide the relative signal strength and general direction of a subject cell phone.[12] If one of the “unique identifying numbers,” like the telephone number, of a cell phone is known, the law enforcement agency can limit the simulator to obtain the signaling information only of that particular cell phone.[13] If one of the cell phone’s unique identifying number is not known, for example, if the individual is using a “burner phone,” the cell-site simulator can acquire it.[14]

Even more concerning than the fact that cell-site simulators enable the police to determine the general vicinity of the cell phone, is that these cell-site simulators also have the capability to intercept the “contents” of communications,[15] as the term is defined in 18 U.S.C. § 2510(8).[16] Most federal law enforcement agencies have adopted internal policies which prohibit the use of a cell-site simulator in this way.[17] This is to avoid violating Riley, a Supreme Court decision prohibiting a warrantless search of content from cell phones absent exigent circumstances;[18] as well as to comply with the federal Pen Register statute, which requires law enforcement agencies to obtain a warrant before employing “a pen register or a trap and trace device.”[19]

While state and local law enforcement agencies are obligated to comply with the Riley standard[20] and the federal Pen Register statute,[21] and thus are not allowed to intercept contents of communications without a warrant, these agencies’ use of cell-site simulators to search for and locate an individual is governed by internal policies or no policies at all.[22] As of 2015, only 18 out of the 24 states that reported having law enforcement agencies that own cell-site simulators have statutes which prohibit warrantless collection of cell phone location information.[23] For example, according to the ACLU Foundation, as of 2015, Kentucky did not have any such legislation which requires law enforcement agencies to obtain a warrant supported by probable cause before utilizing cell-site simulators to identify the location of a cell phone.[24] It is also unknown whether law enforcement agencies in Kentucky have access to such cell-site simulators.[25] Given that state and local law enforcement agencies are not bound by the same internal policies which govern the use of cell-site simulators by federal law enforcement agencies,[26] individual state and local internal policy guidelines may differ in terms of protocol and training requirements for those who operate cell-site simulators in the course of an investigation.[27] State and local law enforcement agencies are not required to adopt the same policies as the DOJ, which require that only certain trained individuals may operate cell-site simulators, in part to ensure that the devices does not intercept content communications.[28] The Supreme Court has not said that state and local law enforcement agencies are required to obtain a warrant supported by probable cause before utilizing a cell-site simulator to identify the location of an individual’s cell phone, even though some federal circuit courts have ruled as much.[29]

Despite the important Fourth Amendment implications which arise from a warrantless use of cell-site simulators during the course of an investigation or apprehension, this issue has not been analyzed by state or federal courts until recently.[30] When light was shed on the government’s use of cell-site simulators in 2008,[31] criminal defendants began to challenge the warrantless use of cell-site simulators as a violation of the Fourth Amendment, and sought to have any evidence obtained during the search to be suppressed at trial.[32] The most recent case involving this issue was decided in September 2017 by the D.C. Court of Appeals.[33] Defendant, Prince Jones, was convicted in 2013 of various counts related to sexual abuse, kidnapping, armed robbery and threats.[34]After obtaining Jones’ cell phone number, and the general location of Jones’ cell phone from the phone company, D.C. Police used a cell-site simulator to locate Jones sitting in a parked car within the area.[35] The D.C. Court of Appeals held that “the use of a cell-site simulator to locate Mr. Jones’s phone invaded a reasonable expectation of privacy and was thus a search.”[36] The D.C. Court of Appeals, in vacating Jones’ conviction and remanding the case back to the trial court, ruled that any evidence which was obtained as a result of the unlawful search must be suppressed.[37]

Even though some lower courts have ruled on the constitutionality of a warrantless use of cell-site simulators during the course of a criminal investigation,[38] until the Supreme Court makes a final ruling on this issue, defendants in jurisdictions where courts have not confronted this issue will have to continue to challenge the admissibility of evidence obtained during such a warrantless search. It seems to be a matter of consensus among the legal community that, because of the Fourth Amendment implications and a desire to avoid a need for further litigation, a final ruling on this issue by the Supreme Court is desirable.[39] It is possible that the recent decision by the D.C. Court of Appeals could result in such a ruling by the Supreme Court, if the government challenges the D.C. Court’s decision.

[1] J.D. expected 2019, University of Kentucky College of Law; B.A. in Sociology, 2016, Western Kentucky University.
[2] Interim Reply from the Executive Office for United States Attorneys’ Offices, Am. Civil Liberties Union (Aug. 12, 2008), https://www.aclu.org/files/pdfs/freespeech/cellfoia_release_074130_20080812.pdf.
[3] Id.
[4] James B. Astrachan & Christopher J. Lyon, Cell-Site Simulators and the Fourth Amendment: Government Surveillance (May 10, 2017), LexisNexis.
[5] Id. (“The news reports similar non-disclosure agreements entered into by law enforcement agencies seeking to purchase cell-site simulators… Typically, the terms of a non-disclosure agreement prohibit the acting law enforcement agency from disclosing any information about the device to the public, and to judges, defense lawyers, and juries.”)
[6] Id.; Daniel Wenner, Stringray Revealed: Cell-Site Trackers and the 4th Amendment, L. 360 (Jan. 25, 2017, 1:51 PM), https://www.law360.com/articles/883130/stingray-revealed-cell-site-trackers-and-the-4th-amendment.
[7] U.S. Const. amend. IV.
[8] See Wenner, supra note 6.
[9] A National Association of Criminal Defense Lawyers Primer: Cell Site Simulators, Berkley L., https://www.law.berkeley.edu/wp-content/uploads/2015/04/2016-4-28_Cell-Site-Simulator-Primer_Final.pdf (last visited Oct. 23, 2017).
[10] Department of Justice Policy Guidance: Use of Cell-Site Simulator Technology at 2 (Sept. 5, 2015), available at https://www.justice.gov/opa/file/767321/download.
[11] Id.
[12] Id.
[13] Id.
[14] A National Association of Criminal Defense Lawyers Primer: Cell Site Simulators, supra note 9.
[15] Astrachan & Lyon, supra note 4.
[16] 18 U.S.C. § 2510(8) (2012) (“‘Contents’, when use with respect to any wire, oral, or electronc communication, includes any information concerning the substance, purport, or meaning of that communication.”).
[17] See Department of Justice Policy Guidance: Use of Cell-Site Simulator Technology, supra note 10 at 3.
[18] Riley v. California, 134 S.Ct. 2473, 2493-94 (2014).
[19] 18 U.S.C. § 3121(a) (2011) (“Except as provided in this section, no person may install or use a pen register or a trap and trace device without first obtaining a court order under section 3123 of this title or under the Foreign Intelligence Surveillance Act of 1978.”).
[20] Riley, 134 S.Ct. at 2493-94.
[21] 18 U.S.C. § 3121(a) (2011).
[22] A National Association of Criminal Defense Lawyers Primer: Cell Site Simulators, supra note 9.
[23] Peter Cihon, Status of Location Privacy Legislation in the States: 2015, Am. Civil Liberties Union (Aug. 26, 2015, 1;15 PM), https://www.aclu.org/blog/free-future/status-location-privacy-legislation-states-2015.
[24] Id.
[25] Stingray Tracking Devices: Who’s Got Them?, Am. Civil Liberties Union, https://www.aclu.org/issues/privacy-technology/surveillance-technologies/stingray-tracking-devices-whos-got-them (last visited Oct. 25, 2017).
[26] See, e.g., Department of Justice Policy Guidance: Use of Cell-Site Simulator Technology, supra note 10 at 2-3 (outlining certain required “management control and approval processes” the DOJ agencies must follow to “help ensure that only knowledgeable and accountable personnel will use the technology.”).
[27] A National Association of Criminal Defense Lawyers Primer: Cell Site Simulators, supra note 9.
[28] See, Department of Justice Policy Guidance: Use of Cell-Site Simulator Technology, supra note 26.
[29] A National Association of Criminal Defense Lawyers Primer: Cell Site Simulators, supra note 9; Tom Jackman, Police Use of ‘StingRay’ Cellphone Tracker Requires Search Warrant, Appeals Court Rules (Sept. 21, 2017), https://www.washingtonpost.com/news/true-crime/wp/2017/09/21/police-use-of-stingray-cellphone-tracker-requires-search-warrant-appeals-court-rules/?utm_term=.fdb533833a87.
[30] Astrachan & Lyon, supra note 4.
[31] Interim Reply from the Executive Office for United States Attorneys’ Offices, Am. Civil Liberties Union (Aug. 12, 2008), https://www.aclu.org/files/pdfs/freespeech/cellfoia_release_074130_20080812.pdf.
[32] See, e.g., State v. Andrews, 227 Md. App. 350, 134 A.3d 324 (2015); see also United States v. Patrick, 842 F.3d 540 (7th Cir. 2016).
[33] Jackman, supra note 29.
[34] Id.
[35] Id.
[36] Id.
[37] Id.
[38] Id.
[39] Wenner, supra note 6; Astrachan & Lyon, supra note 4.

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