MADISON, Wis. — A federal judge ruled Friday that a lawsuit challenging the legality of ICE detainers in Wisconsin county jails must remain under the jurisdiction of the Wisconsin Supreme Court, rejecting an attempt by five county sheriffs to move the case to federal court, according to the ACLU of Wisconsin.
The petition was originally brought by the ACLU of Wisconsin on behalf of Voces de la Frontera, an immigrant rights organization based in Milwaukee, and was filed directly with the Wisconsin Supreme Court in September 2025.
The justices agreed to hear the case in December, the press release states.
The five sheriffs named as respondents then attempted to remove the case to federal court by filing a notice of removal, according to the ACLU of Wisconsin.
The ACLU responded by filing a motion to remand, arguing the sheriffs’ action was not permitted, the ACLU of Wisconsin reported.
A judge in the Western District of Wisconsin agreed, ordering that the matter must be adjudicated by the state’s high court, the press release states.
“We now know that our litigation challenging ICE detainers will proceed before the Wisconsin Supreme Court,” said Tim Muth, senior staff attorney at the ACLU of Wisconsin, as quoted by the ACLU of Wisconsin.
“Immigrants continue to live in constant fear of being falsely arrested and detained by ICE, so ending this illegal practice is no less urgent now than it was when we brought this case,” Muth added, according to the ACLU of Wisconsin.
Voces de la Frontera Executive Director Christine Neuman-Ortiz said she hoped the ruling brought the case closer to accountability, the press release states.
“Hopefully, we are closer to the day when local sheriffs and police can no longer detain innocent immigrants without cause until ICE comes to arrest and deport them,” Neuman-Ortiz said, as quoted by the ACLU of Wisconsin.
At the heart of the lawsuit is the argument that honoring an ICE detainer constitutes an arrest and that Wisconsin law enforcement does not have the authority to make arrests based solely on ICE’s civil administrative warrants, the ACLU of Wisconsin reported.
ICE continues to send hundreds of detainers to Wisconsin jails, and people throughout the state are being held for days so ICE can take them into custody, according to the ACLU of Wisconsin.
ICE sends detainers even for people with no criminal records or people who still have charges pending in Wisconsin courts, the press release states.
In the first seven months of 2025 alone, ICE sent more than 700 requests to local jails across Wisconsin asking them to hold someone for 48 hours beyond when they were scheduled to be released, according to NBC News.
Wisconsin immigration attorney Grant Sovern described the stakes of the case in clear terms, the Wisconsin Examiner reported.
“It is extremely important for the Wisconsin Supreme Court to determine whether any law enforcement in Wisconsin has the legal authority to put or keep people in jail when they have not committed a crime and when no judge has issued an arrest warrant,” Sovern said, as quoted by the Wisconsin Examiner.
The ACLU wants the Wisconsin Supreme Court to prohibit sheriffs from holding people on ICE detainers and establish that holding someone beyond their scheduled release requires a judicial warrant, according to NBC News.
Holding someone for extra time must be authorized by a court that has determined there is probable cause to continue detention, the lawsuit argues, NBC News reported.
Voces de la Frontera Executive Director Neuman-Ortiz framed the broader significance of the case in direct terms, the Wisconsin Examiner reported.
“They are profiling people, they are just grabbing people without any probable cause,” Neuman-Ortiz said. “So it’s a very racist program that is using violence against people and is trying to hijack, through bribery and through threats, local law enforcement to be part of this mass deportation machinery,” as quoted by the Wisconsin Examiner.
Follow the Vanguard on Social Media – X, Instagram and Facebook. Subscribe the Vanguard News letters. To make a tax-deductible donation, please visit davisvanguard.org/donate or give directly through ActBlue. Your support will ensure that the vital work of the Vanguard continues.
