Francisco Sanchez (R) enters court for an arraignment with San Francisco public defender Jeff Adachi (L) July 7, 2015 in San Francisco, California.Getty Images

This article is from the archive of our partner National Journal

The erupting debate over the role of "sanctuary cities" in enforcing federal immigration law has prompted the two parties to invert their usual positions in Washington.

Francisco Sanchez (R) enters court for an arraignment with San Francisco public defender Jeff Adachi (L) July 7, 2015 in San Francisco, California.

Typically, congressional Republicans defend local flexibility and resist federal mandates. Senate Majority Leader Mitch McConnell of Kentucky, for instance, recently wrote all 50 governors urging them to obstruct President Obama's impending regulations requiring states to reduce power-plant carbon emissions. Republicans likewise cheered when the Supreme Court ruled that Washington could not pressure states to expand Medicaid coverage for the uninsured by withholding their existing Medicaid funding.

Conversely, Democrats usually champion unified national action on issues like these. But the two parties switched sides when House Republicans voted earlier in July, over nearly united Democratic opposition, to deny law-enforcement grants to cities that resist federal efforts to deport undocumented immigrants.

These ideological gyrations have obscured the real issue in the emotional debate that was ignited when a repeatedly deported undocumented immigrant randomly shot Kathryn Steinle in San Francisco on July 1. The best estimates are that a smaller share of undocumented immigrants commits serious crimes than other Americans. But all cities would benefit if Washington and localities cooperated more effectively to remove those who are dangerous. The key question is whether the best way to build that partnership is with sticks, which congressional Republicans prefer, or carrots, which Obama is offering.

Some history helps clarify the choice. The term "sanctuary cities" has no specific legal definition; it traces back to policies some cities adopted during the 1980s to support local churches that declared themselves "sanctuaries" for refugees fleeing the era's Central American civil wars. Later, the term encompassed cities that barred police and municipal workers from asking about the immigration status of people they interacted with, or those that prevented police from arresting residents solely because they were undocumented. Even now, neither of those ideas kindles much controversy.

The sanctuary idea really took off as Obama implemented the "Secure Communities" program that George W. Bush had launched shortly before he left office. Under Secure Communities, the fingerprints of almost everyone arrested across America were sent to Immigration and Customs Enforcement to determine their immigration status. If ICE determined that someone in custody lacked legal status, it could issue a "detainer" requesting that local authorities hold the subject for 48 hours after criminal proceedings so ICE could pursue deportation.

Such detainers eventually accounted for about three-fourths of deportations not conducted at the border, the nonpartisan Migration Policy Institute noted in a recent report. But more and more cities balked at cooperating. They complained ICE was deporting not only serious criminals but otherwise law-abiding undocumented immigrants caught for minor offenses — and concluded that cooperating in that dragnet undermined police relations with immigrant communities. MPI calculated that 350 counties and cities (plus three states) that collectively housed more than half of all undocumented immigrants have refused to honor at least some ICE detainers. The list extends beyond liberal enclaves like New York and San Francisco to heartland locales like Wichita and Omaha. "It's definitely lots of small towns, middle America, red states," says Marc Rosenblum, author of the MPI report. Federal court rulings that defined the detainers as requests, not requirements, further discouraged participation.

Facing such widespread resistance, Obama last November replaced Secure Communities with the Priority Enforcement Program. Under that initiative, ICE still checks the fingerprints of everyone who is arrested. But now it asks to be notified only before local officials release undocumented immigrants who have been convicted of serious crimes, or those whom ICE considers a national security threat. ICE seeks extra detention only for those it believes it has probable cause to deport.

Some evidence suggests the new program is attracting more cooperation. Homeland Security Secretary Jeh Johnson recently testified that about 35 large communities have joined PEP, while five have refused. Johnson won't identify the cities cooperating, but Los Angeles County, which had rejected Secure Communities, recently voted to join the new effort.

Marielena Hincapié, executive director of the National Immigrant Law Center, correctly notes that the best way to rebuild federal-local enforcement cooperation is to pass comprehensive immigration reform that reassures cities that the undocumented without criminal records won't be uprooted. Rejecting such reform, congressional Republicans (very few of whom represent urban centers) want to coerce cities into cooperating with funding threats. But as Rosenblum notes, that lever probably isn't strong enough to persuade many dubious cities.

Obama's revised course is more promising. Looking to reach common ground with mostly blue cities on immigration enforcement, he's offering flexible agreements tailored to local concerns (just as he's now doing with red states on carbon reductions and Medicaid expansion). But that balanced approach will work only if liberal cities recognize that refusing to help remove even dangerous felons is an untenable position, as the justifiable outrage over Steinle's death demonstrated. If "sanctuary cities" reject Obama's carrot, they may eventually find themselves facing the Republicans' stick.

This article is from the archive of our partner National Journal.

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