A Green Bay minister and the Wisconsin Council of Churches have brought a petition before the state's top court, seeking a ruling that law enforcement agencies obtain a warrant before accessing license plate reader records — data that, they contend, can expose patterns of religious attendance, including whether individuals are present at Sunday worship.

Several advocacy groups have petitioned the Wisconsin Supreme Court to mandate judicial warrants before law enforcement may access data gathered by automatic license plate readers, contending that the technology accumulates location records that officers can currently retrieve without any court approval. Filed against automated license-plate scanning networks in Green Bay, Milwaukee, Racine, and Kenosha, the petition arrives as a number of Wisconsin localities — stretching from Sheboygan to Milwaukee County — have already begun removing the cameras in response to data-privacy objections.

Two civil liberties organisations — the American Civil Liberties Union of Wisconsin and the Electronic Frontier Foundation — brought the lawsuit on behalf of Green Bay pastor Melissa Pagel and the Wisconsin Council of Churches, a body whose membership spans more than 2,000 congregations across the state.

According to ACLU of Wisconsin attorney Wes Haslam, once this data is shared with police departments or other government bodies nationwide, those receiving agencies hold the ability to reconstruct where a particular person has been over time. Haslam drew attention to the congregations' own programming — among them Alcoholics Anonymous gatherings and support groups for survivors of domestic violence — contending that people who attend those services hold a reasonable expectation that government agencies are not tracking their presence.

No request for a complete prohibition on the cameras forms part of the relief sought through the lawsuit. The organisations have put forward a legal position calling for judicial warrants before authorities can draw on automated license-plate reader archives, contending that unrestricted access to stored location histories raises constitutional privacy concerns.

The lawsuit Haslam described calls for court-imposed limits on mass surveillance tools while also contesting the notion that law enforcement agencies can adequately oversee their own conduct — a position grounded in documented cases of officers in Wisconsin exploiting the data for purposes that included stalking. Law enforcement personnel in both Kenosha and Menasha faced criminal misconduct proceedings in 2026 after an investigation found they had accessed Flock camera databases while off duty to monitor private individuals, among them former romantic partners.

Following an internal review of unauthorised searches, the Milwaukee Police Department reduced access to its Flock database from 370 officers down to 100 during May 2026.

Flock Safety provides the surveillance cameras operating in Green Bay, and municipal representatives have indicated they do not address matters tied to active legal proceedings. In a written statement, Flock noted that its technology captures only static, moment-in-time photographs of vehicles passing through publicly accessible areas — recording licence plates and a narrow set of vehicle attributes — and that neither facial recognition nor identification of vehicle occupants falls within the system's capabilities.

Judicial rulings in over 45 proceedings have held that stationary license plate readers neither breach Fourth Amendment protections nor constitute a means of comprehensively tracking a person's movements, according to the firm's account. To support that position, Flock pointed to a ruling by a Santa Clara County judge who had dismissed a warrant-based challenge to San José's automated license plate reader programme — a case brought jointly by the ACLU of Northern California and the Electronic Frontier Foundation. That ruling established that people driving on public roads hold no protected privacy interest in photographs of their vehicle's licence plates.

In a statement, Flock expressed backing for well-defined laws that would establish accountability measures, oversight mechanisms, and responsible handling of data tied to license plate reader technology.

On October 1, a federal judge sitting in Oklahoma's Northern District handed down a ruling in United States v. Kyle, holding that a police officer's use of Flock Safety's historical license plate reader data without a warrant ran afoul of Fourth Amendment protections. The ruling places state and federal courts on opposite sides of a legal question — namely, whether stitching together fragmented camera footage into a trackable location record amounts to a constitutionally protected privacy interest requiring a warrant.

Cases of this kind — including the one unfolding in Wisconsin — draw heavily on a 2018 ruling the U.S. Supreme Court handed down in Carpenter v. United States, which established that compiling location data over an extended period breaches reasonable privacy expectations, even when each individual movement observed in public would not.

The Wisconsin petition, grounded in the state's own constitutional framework, draws a line between two distinct legal questions: whether a street-mounted camera recording a passing license plate is permissible on its own, and whether aggregating tens of millions of those captures into a time-stamped, queryable database constitutes a separate act requiring a court's prior approval.

A lawsuit lodged by the Wisconsin Institute for Law and Liberty on September 10 named Waukesha County and 11 municipalities as defendants, with the filing contending that external law enforcement bodies conducted approximately three million database queries against local Flock camera records without warrants across a three-month period in 2026.

Legislation prohibiting Flock camera installations throughout Milwaukee County's park system received David Crowley's signature, with data-privacy considerations driving the county executive's decision, according to a news outlet. Prior to that point, camera-based traffic enforcement had already been wound down across three Wisconsin localities — Sheboygan having decommissioned all 15 of its devices, Stevens Point having suspended activity at each of its 10 installations, and Dane County having allowed its contractual arrangement to expire without renewal.

On September 15, two House members — Raja Krishnamoorthi of Illinois and Michael Cloud of Texas, crossing party lines — put forward legislation that would instruct the U.S. Secretary of Transportation to hold back 10 percent of federal surface transportation funds from any state that does not confine automated license plate reader use to five designated public-safety purposes.

The fate of the warrant requirement in Wisconsin now rests on a single procedural step — a petition awaiting action from the state supreme court. The organisations expressed a desire for the lawsuit to push law enforcement agencies toward clearer public disclosure and stronger oversight of how surveillance tools of this kind are put to use.