Wisconsin Supreme Court puts ICE detainers suit on hold pending appeal

• The Wisconsin Supreme Court has paused a case challenging the legality of ICE detainers.
• This hold will remain until a federal appeals court decides which court has jurisdiction.
• The lawsuit, filed by the ACLU, seeks to stop Wisconsin sheriffs from holding immigrant detainees for federal authorities.

MADISON – The Wisconsin Supreme Court is putting on hold a case challenging the legality of ICE detainers in Wisconsin until federal judges determine whether they will reconsider where the case should be tried.

In its July 6 order, the state Supreme Court also held off on deciding whether to allow the U.S. government to join the case, which seeks to block county jails from holding immigrant detainees at federal authorities’ request.

The case continues to sit in jurisdictional uncertainty. It’s currently under the state Supreme Court’s purview, but the county sheriffs being sued have asked a federal appeals court to take it.

The court’s order seeks to “avoid potential uncertainty and conflict” as the federal appeal plays out.

The American Civil Liberties Union of Wisconsin filed the lawsuit in September 2025, on behalf of the immigrant advocacy group Voces de la Frontera, against five Wisconsin sheriffs who have partnered with U.S. Immigration and Customs Enforcement to house immigrant detainees, an action known as a detainer.

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The state’s highest court agreed to take the case in December 2025, but the five sheriffs named in the lawsuit – Dave Gerber of Walworth County, Todd Delain of Brown County, Chad Billeb of Marathon County, David Zoerner of Kenosha County and Chip Meister of Sauk County – sought to have the case moved to federal court.

U.S. District Judge William Conley on May 15 issued an order remanding the case back to the state Supreme Court, and the sheriffs filed an appeal of Conley’s ruling with the 7th Circuit Court of Appeals on May 26.

Last month, Voces de la Frontera asked the state Supreme Court to set a briefing schedule to run simultaneously with the federal appeal, while the sheriffs asked the state’s high court to grant a stay pending the resolution of their appeal.

And last week, the federal government filed a motion to intervene in the case at the state level.

The state Supreme Court’s July 6 order denies Voces de la Frontera’s request to allow the case to proceed at the same time as the federal appeal and does not address the U.S. government’s motion to intervene.

The case now awaits action from the 7th Circuit Court of Appeals.

When a sheriff honors a detainer from ICE, they agree to hold a person for 48 hours after they would have been released under state law to give ICE time to pick up and take custody of the person.

The ACLU is asking the state Supreme Court to declare that civil immigration violations are outside the authority of a law enforcement officer in Wisconsin, and to prohibit the sheriffs from holding people on ICE detainers.

The sheriffs said in their response to the lawsuit last year that their offices have worked with ICE for decades and some have been trained by ICE to serve administrative warrants on their behalf.

Attorney Sam Hall, who represents the sheriffs, has argued throughout the case that the issue should be resolved at the federal judicial level. ACLU of Wisconsin attorney Tim Muth has accused the sheriffs of using “repeated delay tactics.”

Jessie Opoien can be reached at jessie.opoien@jrn.com.