Surveillance State: How Stingray Technology Undermines Fourth Amendment Rights

Surveillance State: How Stingray Technology Undermines Fourth Amendment Rights

By Maxwell Mrus | Staff Editor

April 30, 2024

The freedom against unreasonable searches and seizures is a keystone of American civil liberties. The Fourth Amendment prevents governmental actors from unreasonably invading Americans’ homes, cars, effects, or persons without probable cause to do so.[1] But what about at protests? Obviously, police officers have the ability to search an individual suspected of criminal behavior at protests. But, what about warrantless searches of a wide swath of individuals without their knowledge?

With cell-site simulator (or “Stingray”) technology, police departments can search and seize a variety of data from the cellphones of any individuals in the technology’s vicinity entirely inconspicuously.[2] Stingray technology, in essence, acts as a fake cell-phone tower and forces cellphones in its area to automatically connect to it.[3] Once connected, Stingray technology can obtain the locational information, identifying data, and metadata of that cellphone.[4] Put simply, this military-grade technology[5] can track a phone, identify its unique identification number, and view a variety of personal communications—all without the user’s knowledge.[6]

Further, this technology is a brute. Especially when used at protests, anyone with a cellphone in attendance is likely being tracked and farmed for data – even without presenting a suspicion of probable cause. Chances are, if you have attended a protest in recent years, you have likely been subject to such a search. And, in most states, police departments do not even need a warrant to use Stingray technology.[7] As a result, American police departments can trample the constitutional rights of countless Americans simply to search a haystack for a single needle.

Historically, police surveillance has disproportionately targeted marginalized communities.[8] These historic trends continue today.[9] Policing biases are further entrenched by use of surveillance technologies.[10] And these technologies are disproportionately deployed in marginalized, overpoliced communities.[11]

There are few instances of case law dealing directly with Stingray technology. The Supreme Court, however, has encountered this issue—yet, only from afar. Carpenter established the rule that Americans have a “reasonable expectation of privacy” in their locational data that can be gleaned from a Stingray search.[12] As a result, if an American has their locational data searched and seized, then it becomes a Fourth Amendment violation.[13]

Regulation of this technology is sparse and typically enacted on a state-by-state basis, usually following a court case. With no federal regulation, procedures and practices governing the use of Stingray technology differ greatly – allowing some states to skirt constitutional protections. To account for this patchwork regime of regulation, the federal government must step in. Regulation at the federal level would eliminate “confusing” and “overlapping” policies and laws at the state and local levels while providing “clear legal standards” for use of Stingray technology by any government agency.[14]

The Cell-Site Simulator Warrant Act of 2021 provided a model for such federal regulation.[15] This Act established a warrant requirement for use of Stingray technology by any governmental agency. Further, on the warrant application, the agency would have to disclose the data to be collected, any potential third-parties that may be inadvertently impacted by the search, and whether it was to be used at an event with constitutionally-protected activity, such as a protest.[16]

Despite being a bipartisan issue, this Act unfortunately died in committee,[17] leaving no practical alternative at the federal level. Thus, for the foreseeable future, it appears that the state-by-state regulation regime will continue, being spurred only by judicial challenges after constitutional violations have already occurred.

But the American people deserve more. Instead of relying on a retroactive vindication of their constitutional rights, state and federal governments must provide proactive protections for protestors. Further, police departments have a multitude of other resources to rely on to catch criminals; most of which do not subject the masses to unconstitutional searches merely for participating in the expression of grievances.

During our tumultuous time, Americans must be able to freely express their grievances without fear of being tracked and farmed for data. Otherwise, protestors, regardless of their intentions, come to be viewed under an air of suspicion, can be freely searched without their knowledge, and fall victim to the surveillance state.

[1] U.S. Const. amend. IV.

[2] Street-Level Surveillance: Cell-Site Simulators/ IMSI Catchers, Electronic Frontier Foundation (last updated on Aug. 28, 2017),

[3] Id.

[4] Id.

[5] See John Haystead, Optical Warfare: Technology Emerges to See the Enemy, and to Blind Him, Military Aerospace Electronics (Mar. 1, 1997),

[6] Street-Level Surveillance: Cell-Site Simulators/ IMSI Catchers, Electronic Frontier Foundation (last updated on Aug. 28, 2017),

[7] See Status of Location Privacy Legislation in the States, American Civil Liberties Union (Aug. 26, 2015),

[8] See Jeffrey L. Vagle, Tightening the OODA Loop: Police Militarization, Race, and Algorithmic Surveillance, 22 Mich. J. Race & L. 101, 124–26 (2016).

[9] See George Joseph, Racial Disparities in Police ‘Stingray’ Surveillance, Mapped, Bloomberg (Oct. 18, 2016),

[10] See supra note 8.

[11] Id.

[12] Carpenter v. U.S., 138 S. Ct. 2206, 2217 (2018).

[13] See id. at 2219.

[14] Press Release, Ron Wyden: United States Senator for Oregon, Wyden, Lieu, Daines and McClintock Introduce Bipartisan Legislation to Require Warrants for Government Use of “Stingray” Phone Surveillance (June 17, 2021),

[15] S. 2122, 117th Cong. § 3119.

[16] S. 2122, 117th Cong. § 3119(a)(1)(A)–(C).

[17] Congressional Research Service, S.2122 – Cell-Site Simulator Warrant Act of 2021,,

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