It appears to be the first Justice Department lawsuit against local officials for allegedly interfering with the Trump administration’s immigration crackdown.

The lawsuit argues the U.S. Constitution’s Supremacy “prohibits Illinois, Chicago, Cook County, and their officials from obstructing the Federal Government’s ability to enforce laws that Congress has enacted or to take actions entrusted to it by the Constitution.”

Federal officials are asking a judge to bar the Illinois, Chicago, Cook County and the Cook County Sheriff from using local laws that protect migrants to hamper law enforcement.