In the wake of a San Francisco shooting that garnered national attention, the immigration debate has centered on sanctuary cities.

Sanctuary policies differ from city to city, but generally the policies instruct city employees and law enforcement to not ask the immigration status of criminal suspects.

According to the Center for Immigration Studies, more than 200 cities and counties in the United States have policies that make them immigration sanctuaries.

>>> Is Your City a Sanctuary City? This Map Has the Answer.

Proponents of sanctuary cities say this policy is necessary in balancing public safety with a respect for civil rights, maintaining trust in immigrant communities to continue to fight crime.

Opponents argue that sanctuary policies endanger local communities. By ignoring a criminal’s immigration status, it shields convicted criminals from deportation, releasing some back into the community.

But what exactly is a sanctuary city? Learn more in the video above.

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