The Department of Justice has filed a lawsuit against Colorado and Denver, accusing them of impeding federal efforts to enforce immigration laws, in the latest move by the Trump administration targeting sanctuary cities and policies. The lawsuit alleges that Colorado and Denver have enacted “sanctuary laws” that violate the Supremacy Clause of the U.S. Constitution, which asserts federal authority over immigration matters. Sanctuary policies generally involve limited local cooperation with Immigration and Customs Enforcement (ICE), particularly regarding large-scale deportations.

Notably, the lawsuit claims that Colorado’s sanctuary policies enabled the Venezuelan gang Tren de Aragua to take control of an apartment complex in the Denver suburb of Aurora. While local officials dispute Trump’s claims about the gang’s influence, they acknowledge issues at the complex involving individuals linked to Tren de Aragua.

The lawsuit names Democratic Governor Jared Polis, the state Legislature, Denver Mayor Mike Johnston, and Colorado Attorney General Phil Weiser as defendants. Polis’s spokesperson emphasized that Colorado collaborates with various law enforcement agencies and will abide by court rulings regarding state laws.

Republicans in Congress have been urging officials in Democratic-led cities to cooperate with the Trump administration’s immigration agenda. In response, mayors of major cities like Denver, Boston, New York, and Chicago have defended their communities as welcoming places and advocated for comprehensive immigration reform during a recent congressional hearing.