The ACLU of Colorado said it filed suit Monday against Teller County Sheriff Jason Mikesell, alleging that he violated the law by detaining a suspected illegal immigrant strictly at the request of federal immigration authorities.

The suit over inmate Leonard Canseco Salinas alleges that an Immigration and Customs Enforcement detainer falls short of what the law requires before incarcerating someone: a warrant or sentencing order signed by a judge.

The 12-page complaint was filed in Teller County District Court and names no other defendants. It marks the civil liberties group’s latest attack on what it has called illegal detention practices in which ICE asks jailers to hold suspected illegal immigrants until federal agents can take them into custody. Mikesell wasn’t available for comment.

This year, the ACLU won a judge’s preliminary injunction barring the El Paso County jail from honoring ICE detention requests pending an earlier lawsuit over the practice in Colorado Springs.

That class-action suit argued that county Sheriff Bill Elder illegally jailed dozens of inmates without orders signed by a judge. The County Attorney’s Office has called the detainers lawful and denies wrongdoing.

In the Teller County case, Canseco, 44, was arrested July 14 on suspicion of two misdemeanors. He should be eligible to post an $800 bond, the ACLU said, but authorities won’t allow his release because ICE has asked that he be detained.

The ACLU of Colorado said numerous Colorado sheriffs in 2014 said they would not honor ICE detainers. That year, the organization negotiated a $30,000 settlement with Arapahoe County on behalf of Claudia Valdez, a domestic violence victim who was held for three days under an ICE detainer until a judge ordered her release.