Court Cases

The ACLU of Colorado filed a class action lawsuit in federal court seeking to declare that ICE and DHS’s new practice of denying release on bond to groups of noncitizens violates federal law.

The ACLU of Colorado filed a class-action lawsuit against the Trump administration to enjoin ICE from conducting warrantless arrests in Colorado without probable cause that the person is a flight risk and in the country without proper legal documentation. On November 25, 2025, a federal judge found ICE had unlawfully arrested each of the named plaintiffs, certified a class of similarly situated individuals, and enjoined ICE from arresting anyone in Colorado without a warrant without first making the probable cause findings required by law.

The ACLU of Colorado sued the Elizabeth School District because it banned and removed at least 19 books from school libraries based on the school board’s disagreement with the ideas they contain. The plaintiffs include students who have a right to access those books.

ACLU of Colorado filed a lawsuit against ICE to obtain additional records regarding the agency’s ramp-up plans to expand immigration detention across Colorado and Wyoming. The government has since produced heavily redacted documents revealing some new information about ICE's plans.

The ACLU of Colorado moved to intervene on behalf of Common Cause and individual Colorado voters in a federal lawsuit over the federal government’s demand that Colorado turn over its entire voter registration rolls, including voters’ sensitive personal data.

The ACLU of Colorado filed an amicus brief arguing that Colorado’s Sexually Violent Predator designation is punishment.