Shortly after his inauguration, President Trump signed an executive order designed to cut off federal funding to sanctuary cities.

Via the Los Angeles Times:

The Justice Department on Friday fired an opening shot in the Trump administration’s crackdown on so-called sanctuary cities, sending letters to nine jurisdictions asking for proof that they are cooperating with immigration enforcement, and indicating they are at risk of losing federal grants.

The letters went to the California Department of Corrections and Rehabilitation, as well as officials in Chicago, New Orleans, Philadelphia, Las Vegas, Miami, Milwaukee, New York and Cook County, Ill.
…
The letters say a lack of cooperation might mean the jurisdictions are in violation of their agreements concerning Justice Department grants.

The department hands out $2.2 billion each year to localities to support anti-crime efforts.

Some cities already have begun an effort to resist the pressure from the Trump administration. Seattle has already filed a federal lawsuit asking a court to declare that it can refuse to help the new immigration crackdown.

This is not a new problem, in fact, the underlying authority used by Justice for these warning letters is a Clinton-era federal law:

Recipients of the letters were warned that to receive certain fiscal year 2016 grants, they must certify by June 30 that they have complied with a 1996 federal law that bars local authorities from forcing officials to withhold information from federal immigration authorities about people’s immigration status.

Sanctuary cities are a problem but cutting off funding is not as easy as it sounds. A lot of federal money is apportioned out to states or to regional transportation cartels or metropolitan areas comprising multiple jurisdictions so removing funding from a city can be very difficult. As a result, Ground Zero in this battle against legitimized lawlessness has become Justice Department grants. These are targeted at the municipal level and it is easy to crosswalk grantees to immigration policies. Plus, as grant applications are a voluntary exercise on the part of the municipality, if the Justice Department makes cooperating with ICE a factor in awarding the grant there is no conflict with Printz vs. US. They aren’t being deprived of funds they are legally entitled to, like, perhaps, gasoline tax revenues. If the municipality does not want to abide by the grant provision it doesn’t have to.