When President Donald Trump opened Twitter on Wednesday morning, it was to tear into the source of one of his greatest frustrations: Sanctuary cities, the sites of astounding rates of crime and violence perpetrated by undocumented immigrants who violate the law under the protection of liberal mayors who provide them refuge.
According to Trump, that is.
"There is a Revolution going on in California," the president wrote early Wednesday morning. "Soooo many Sanctuary areas want OUT of this ridiculous, crime infested & breeding concept. Jerry Brown is trying to back out of the National Guard at the Border, but the people of the State are not happy. Want Security & Safety NOW!"
But experts say there's no evidence that sanctuary cities—cities, or in some cases counties, that limit their involvement with federal law enforcement to defend law-abiding immigrant residents against deportation—give way to higher rates of crime.
"Every country, and of course the U.S. too, has the right to secure its borders and define its immigration policy, including dealing with illegal immigration," Dany Bahar, a fellow at the Brookings Institution, told Newsweek Wednesday. "But let’s be honest on the motivations to do so. When it comes to crime, the evidence does not fully support the statement made by the president."
Several studies have drawn conclusions to this effect. In October 2016, before Trump's election, researchers from the University of California, Riverside and Highline College examined 54 sanctuary cities using two different methods, to see if there was any significant difference in those cities' crime levels. They found none.
"Our findings provide evidence that sanctuary policies have no effect on crime rates, despite narratives to the contrary," they wrote. "The potential benefits of sanctuary cities, such as better incorporation of the undocumented community and cooperation with police, thus have little cost for the cities in question in terms of crime."
Since then, the FBI has provided its own data on crime rates in the country, including in sanctuary cities, which supports these findings.
In January, the bureau published preliminary results, which showed that the rate of violent crime had decreased by 0.8 percent in the first six months of 2017, when compared to the same period of time the year prior. That included cities like New York and Chicago, which both saw drops in murders and shootings.
At the time, Washington Post columnist Jennifer Rubin declared the findings "bad news for the phony war on 'sanctuary cities.'"
Some research even suggests that sanctuary cities may actually be safer than non-sanctuary cities for all residents, not just immigrants.
After studying 33 sanctuary cities, Mike Males, a senior research fellow at the Center on Juvenile and Criminal Justice, found that white residents of sanctuary cities were far less likely to die from illegal drug overdoses or from any violent crime. Residents of color saw benefits, too.
“The impact of sanctuary cities on people of color is less consistent,” Males told The Crime Report in December. "But overall, African-American, Latino, Asian, and Native American residents generally experience greater safety in counties with at least some sanctuary policies."
The White House did not immediately return Newsweek's request for comment.
But the Trump administration has been steadfast in admonishing sanctuary cities.
In October, Attorney General Jeff Sessions warned a handful of sanctuary cities that they had just one "last chance" to comply with federal laws the Department of Justice believed they were violating. A month later, the DOJ sent letters to 29 cities, counties and states, telling them they were breaking the law by not cooperating with federal agents.
Sessions and the administration continued to escalate its warnings to sanctuary cities, to the point where, in January, Department of Homeland Security Secretary Kirstjen Nielsen said the DOJ was considering criminal charges and arrests for mayors of sanctuary cities who weren't compliant.
"The Department of Justice is reviewing what avenues might be available,” Nielsen said. “The context of this is of course not only putting my [Immigration and Customs Enforcement] officers at risk, but also finding an efficient and effective way to enforce our immigration laws.”
The Trump administration's opposition to sanctuary cities may be a self-defeating one, according to Bahar. Immigrants don't bring crime, he pointed out—but they do bring jobs.
"Trump is ignoring the vast evidence showing the fact that migrants are highly entrepreneurial ... and thus generate jobs," Bahar said. "If he’s so keen on generating jobs, then the answer to that is not less, but rather more migration."
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