A GOP-led committee questioned mayors Wednesday on their limited cooperation with federal immigration authorities. Boston's Mayor Wu has argued the policy keeps the city safe and builds trust with diverse communities.

Mayors from Boston, Chicago, Denver and New York are set to testify in Congress as Republicans take aim at “sanctuary cities” policies

Democratic mayors of four major cities say Congress and the Trump administration are exaggerating crime committed by immigrants and attacking so-called sanctuary cities simply to score political points,