MINNEAPOLIS (WCCO) — President Donald Trump reiterated his threat to take away funding sanctuary cities ahead of Tuesday’s visit to California.

“Lawless sanctuary jurisdictions are nullifying federal law, obstructing immigration enforcement and releasing thousands of criminal aliens into U.S. communities to prey on innocent victims,” Trump said during his weekly radio address.

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But supporters say sanctuary cities do not prevent Homeland Security from making arrests, and allow immigrants to more safely interact with their community and police.

So, what exactly are sanctuary cities, and how are they defined? Virgil Wiebe, professor at the University of St. Thomas School of Law, says it is an emotional, political and legally-murky term.

(credit: CBS)

“At the very basic level, there’s not a definition,” Wiebe said. “The issue is what level are local jurisdictions cooperating with immigration enforcement.”

What some consider limited cooperation can range from a number of different actions, including jurisdictions not asking about immigration status, not deputizing local law enforcement as ICE agents, not giving ICE advance notice when immigrants are released from jail and not detaining people for extra time so ICE can get them.

Many of those detainers have been ruled unconstitutional by the courts.

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Counting sanctuary cities can be difficult because there are so many different definitions and law.

Five states — California, Oregon, Rhode Island, Connecticut and Vermont — have state laws that limit cooperation between local law enforcement and ICE. The conservative Center for Immigration Studies lists what it considers 300 sanctuary jurisdictions across the country.

Attorney General Jeff Sessions put 23 cities — including Los Angeles, New York and Chicago — on its sanctuary city list earlier this year.

Neither St. Paul or Minneapolis call themselves sanctuary cities. Instead, the city of Minneapolis prefers to call itself a “Welcoming City.”

In an op-ed to the Pioneer Press, former St. Paul Mayor Chris Coleman wrote, “The City of Saint Paul wants all its residents to feel comfortable.” He also said St. Paul does not provide safe harbor to criminals.

Both cities have a “separation ordinance,” which prohibits city employees — including police — from asking people their immigration status.

As for Hennepin County, a spokesperson said the county does cooperate with immigration officials, but will not hold people for ICE after local charges have been settled.

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“In many ways, it’s being battled out in the courts as to what this means,” Wiebe said. “But it’s also a perception battle as well.”

Heather Brown