MILWAUKEE (CBS 58) -- A lawsuit challenging immigration enforcement activity in Wisconsin is headed to the state Supreme Court. 

According to the ACLU of Wisconsin, federal ICE agents have been detaining immigrants in Wisconsin jails until ICE can pick them up. 

The ACLU has filed a lawsuit on behalf of the advocacy group Voces de la Frontera. 

The suit argues that ICE detention is the same as an arrest, and Wisconsin law enforcement officers do not have the legal authority to make arrests based on ICE warrants. 

The Wisconsin Supreme Court will now consider that argument.