The lawsuit argues that the U.S. Constitution’s Supremacy Clause “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.”

Illinois Democratic Gov. JB Pritzker says the state follows the law. President Donald Trump has often singled out Chicago and Illinois, which have some of the strongest sanctuary laws in the U.S.