President Trump imposed a new federal policy on Wednesday that could lead to the stripping of federal funds to state and local jurisdictions that refuse to comply with federal immigration laws, known broadly as “sanctuary cities.”

Republicans have been fuming for years over President Obama’s acceptance of sanctuary cities, even after events in which illegal immigrants are set lose by local jurisdictions and commit violent crimes. The murder of Kate Steinle in San Francisco by a man who had been deported several times before became a rallying point for conservatives who were demanding zero tolerance for sanctuary cities.