CHICAGO (AP) — The ACLU of Illinois and other advocacy groups have sued two county sheriffs for alleged violations of the TRUST Act, which limits cooperation between local police and federal immigration authorities.

It’s part of an effort announced Thursday to monitor law enforcement compliance of the 2017 law prohibiting local police from holding a person on an immigration detainer unless there’s a judge-signed warrant.

READ MORE: Mayor Lori Lightfoot Asks Bidders For Chicago Casino To Submit Formal Plans By August 23

The lawsuits allege sheriffs in Stephenson and Ogle counties unlawfully detained immigrants for U.S. Immigration and Customs Enforcement after minor traffic offenses. Stephenson County Sheriff David Snyders’ attorney says it’s clear county employees complied with laws. The Ogle County sheriff didn’t return a Thursday message.

READ MORE: Cook County Health Offers Walk-In COVID Vaccines At Tinley Park, Matteson Mass Vaccination Sites Through Saturday

Activist Mony Ruiz-Velasco says authorities “cannot view the TRUST Act as optional.”

Republican former Gov. Bruce Rauner signed the law in 2017 with backing from law enforcement. Democrats supported the idea.

MORE NEWS: Wrong Vaccine Accidentally Administered At Mariano's In Aurora

(© Copyright 2019 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)