A Minnesota judge has issued a temporary restraining order that bars the Nobles County Sheriff's Office from relying on arrest warrants from immigration officials to keep individuals detained.
The southern Minnesota county is appealing the order.
The Minnesota chapter of the American Civil Liberties Union sued Nobles County this year, alleging the sheriff's office didn't release some immigrants from jail when required, then re-arrested them for Immigrations and Customs Enforcement.
An attorney for the county said it doesn't arrest people for ICE. But Nobles County has a contract to house ICE detainees, and transitions into ICE custody were done if paperwork was in order.
Friday's order says the county can't rely on ICE arrest warrants because they aren't signed by a judge.
The order means that the county must now release individuals and an ICE official must re-arrest them if they are to be placed in federal custody.
In a statement, an attorney for Nobles County said this case, like others filed by the ACLU across the country, is intended to force counties to become "sanctuary counties."
MPR News contributed to this report.