What is a ‘sanctuary city’ and what do politicians mean by it?

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What is a sanctuary city really? How politicians use a politicized term to frame the immigration debate

When Republican Florida Gov. Ron DeSantis commissioned a plane to fly migrants to Martha’s Vineyard, one of the reasons he chose that location, he said, was because it was a “sanctuary jurisdiction.”

But what is a sanctuary city or state? The concept has no real legal basis and is often thrown around in immigration debate, both by those advocating for more humane treatment for migrants and by those pushing for harsher immigration restrictions. The term “sanctuary city” can mean exactly what the user wants it to mean, depending on their motivations.

Sanctuary cities emerged in the national conversation after the election of Donald Trump in 2016, when cities like Chicago and Washington, D.C., wanted to position themselves as welcoming to migrants — and in opposition to the Republican president’s anti-immigration sentiments. There’s no list of sanctuary cities — but elected officials in blue states and cities began to claim the term as means of opposing Trump. “Chicago has in the past been a sanctuary city. … It always will be a sanctuary city,” the former Chicago Mayor Rahm Emanuel said after the election.

We talked to experts about the oft used (and malleable) term that has become such a part of one of the biggest debates shaping the midterm elections.


It can be a symbolic label

While many jurisdictions, such as Washington, D.C., have declared themselves sanctuaries, they don’t have special power to override U.S. Immigration and Customs Enforcement (ICE).

One of the biggest misconceptions, said Benjamin Gonzalez O’Brien, a political science professor at San Diego State University and co-author of Sanctuary Cities: The Politics of Refuge, is that sanctuary jurisdictions prevent ICE from doing its job — this is not the case. While local law enforcement officers aren’t legally required to assist ICE, they can’t forbid the agency from conducting raids or taking people into custody.

“It doesn’t really shield members of the community who may lack legal status,” he said.

Sanctuary cities exist along a continuum, Gonzalez O’Brien said. A city’s policies can affirm its dedication to diversity and inclusiveness, he said, or specifically forbid police from cooperating with ICE.

What powers cities and states have over what happens to migrants

That said, added Gonzalez O’Brien, there are actions jurisdictions can take — either to support or prosecute migrants.


One of the major aspects of that is how much or how little police on the local level are directed to cooperate with ICE, said Lena Graber, a senior staff attorney at the Immigrant Legal Resource Center, a research and advocacy nonprofit organization for immigrant rights. There are several local policies and state laws that carve out a locality or state’s role in immigration enforcement, which local jurisdictions can opt out of.

For example, under the Illegal Immigration Reform and Immigrant Responsibility Act of 1996, localities can opt to sign (or opt not to sign) what’s called a 287 (g) agreement with ICE. By signing this agreement, local law enforcement officers can be deputized as immigration agents and assist ICE in interrogating, detaining and deporting people.

Jurisdictions can also pass laws preventing police officers from asking about immigration status or sharing information about undocumented immigrants with ICE.

And many sanctuary policies, Gonzalez O’Brien and Graber said, decline to honor immigration detainers (also known as “ICE holds”), which only became popular in the last 15 years or so. These are requests that local jails hold a person, even after someone should be released from jail, until ICE takes them into custody.

As immigration enforcement priorities change, some cities, like San Francisco, have responded accordingly by, for example, updating their sanctuary policies with ordinances declining to cooperate with ICE holds.


The rise of the idea of “sanctuary cities”

While the movement really started in the 1980s when asylum-seekers were arriving in the U.S. from El Salvador and Guatemala, it was on the heels of 9/11 and the formation of ICE and the Department of Homeland Security in the early aughts that it became highly politicized. As ICE ramped up immigration enforcement, many communities pushed back against a spike in detentions and deportations, Graber said.

Before former President Donald Trump’s campaign, presidential administrations and members of Congress generally ignored these “sanctuary city” policies, which they largely viewed as a way to generate national media attention to the plight of asylum-seekers and the nation’s immigration, refugee and asylum policies, said Gonzalez O’Brien.

Sanctuary jurisdictions came to the forefront of the national conversation in 2015, when Kate Steinle was accidentally shot and killed by an undocumented immigrant, later acquitted for homicide charges, who had been released by the San Francisco Police Department under the city’s sanctuary policy months earlier.

A wave of anti-sanctuary laws

Trump vowed to crack down on sanctuary cities by blocking federal funding.

“The former president … really elevated the issue of sanctuary specifically onto the national agenda, and turned it into a highly politically, polarized issue,” Gonzalez O’Brien said. “We see a lot of fear mongering, and historically we’ve seen a lot of fear mongering around undocumented immigrants and immigrants more broadly.”

The White House went so far as to publish a list of “criminal noncitizens shielded from ICE officials” and, even in his 2020 State of the Union address, the former president Trump erroneously claimed that in these cities, “local officials order police to release dangerous criminal aliens to prey upon the public.”

“A lot of Americans didn’t know a lot about these policies,” said Gonzalez O’Brian. “It was really easy to craft a narrative around them that they’re setting dangerous criminals free, that democratically run cities that have sanctuary policies in place are havens for drugs and crime and everything else that the former president claimed was associated with undocumented immigration.”

The politicization of sanctuary policies has tangible impacts on the passage of anti-sanctuary laws, the willingness of residents to interact with the police and report crimes and what immigrations and customs enforcement looks like on the ground.

With Trump came a wave of anti-sanctuary — and generally anti-immigrant — laws, now extending to roughly 97 million people, according to analysis by the Immigrant Legal Resource Center (LRC) from last week.

These policies can range from prohibiting local governments from enacting sanctuary policies or mandating assistance to ICE, the LRC said. Before Trump, just Arizona and a couple of other states passed anti-sanctuary, “show me your papers,” laws.


Texas passed a law called SB4 in May 2017, which required localities and college campuses to assist ICE by sharing information about and helping to detain noncitizens. Conservatives also added a provision to their “show me your papers” laws to let police ask about the immigration status of not just those they arrest, but also those they detain, such as a suspect getting questioned.

The consequences of anti-sanctuary laws

States with anti-sanctuary laws can see serious consequences on interactions with local police. Research from the U.S. Immigration Policy Center at the University of California, San Diego suggests that if immigrant communities believe local law enforcement is cooperating with ICE, they may be less likely to interact with police in general, meaning they may be less likely to report crimes, even as witnesses.

In Texas, for instance, Gonzalez O’Brien and his co-author, Loren Collingwood, an associate professor in the Department of Political Science at the University of New Mexico, wrote in their book that with increased immigration enforcement came a decline in 911 calls, especially around domestic violence or sexual assault. Even before the Texas laws took effect, Houston police said fewer people were willing to interact with law enforcement, the Intercept reported in 2017.

While some of these policies are largely symbolic, perceptions matter. The recent spate of political stunts pulled by politicians only redirect attention away from bipartisan conversations to be had around immigration. “What we see DeSantis doing in Florida right now,” Gonzalez O’Brien said, “is a direct consequence of seeing how successful Donald Trump was in turning immigration into a political issue that you can run on.”

Thanks to Alicia Benjamin for copy editing this article.

  • Anna Deen
    Anna Deen

    Data Visualization Reporter

    Anna Deen is a data visualization reporter at Grid.