American churches coined the phrase, but among Republican presidential candidates, "sanctuary city" has become a dirty word.
At Wednesday's GOP presidential debate, the issue sparked hard-edged exchanges between two of the leading contenders for the party's nomination. Mitt Romney accused Rudolph W. Giuliani of running a "sanctuary city" as mayor of New York because of policies that shielded illegal immigrants from being reported to federal authorities. Giuliani disputed that label, and derided the former Massachusetts governor for living in what he called a "sanctuary mansion" where illegal immigrants did contract work.
The spat drew applause and catcalls, reflecting how contentious the issue of immigration has become for voters and candidates in the 2008 primary campaign.
Most of the GOP White House contenders and many conservative activists use the sanctuary term to attack local government policies that they believe sanction, and even encourage, illegal immigration.
But experts say the phrase means different things in different places. Initially, the idea sprang from humanitarian outreach in the 1980s by churches and immigration support groups that urged U.S. communities to create havens for the victims of civil wars raging in parts of South and Central America.
Most of these cities adopted "don't ask, don't tell" policies, under which city employees, including police officers, were not required to report illegal immigrants to federal authorities.
In defending the police aspect of such policies, Giuliani said during the debate: "If we didn't allow illegals to report crimes [without the fear of deportation], a lot of criminals would have gone free because they're the ones who had the information."
Others argue that the protection was needed for illegal immigrants to keep them from being targeted by criminals, who would not have to fear that their victims would turn to the police.
Some cities made the decision not to deny services on the basis on immigration status so that illegal immigrant residents could have access to public libraries or send their children to local schools. Others, such as San Francisco and New Haven, Conn., have issued municipal IDs that allow residents, including illegal immigrants, to function within the city.
"There are gradations of different policies, but there's no working definition," said Laureen Laglagaron, a policy analyst at the Migration Policy Institute, a nonpartisan think tank.
An upcoming institute study identified 73 cities, spread across 26 states, as sanctuaries. These include Los Angeles, Fresno, San Diego and San Francisco.
New York is on the list for allowing illegal immigrants to send their children to schools, use the public health system and report crimes without fear of arrest because of their status. Cambridge, Mass., also made the list.
Giuliani, at the debate, charged that Massachusetts had half a dozen sanctuary cities that Romney had not acted against as governor.
Romney disputed that claim.
At one point, Giuliani sought to take Romney to task for what he said was an undeserved "holier-than-thou attitude" about combating illegal immigration.
Romney interrupted. "I'm sorry, immigration is not holier than thou, Mayor. It's the law."Copyright © 2015, Los Angeles Times