Senator Tom Cotton of Arkansas introduced a bill on Wednesday that would deny federal law enforcement aid to cities that don't comply with federal immigration laws. The problem of so-called "sanctuary cities" has been in the news following the murder of Kathryn Steinle, a young woman who was killed in the sanctuary city of San Francisco by an illegal immigrant who had seven felony convictions and had been deported five times. 

"The senseless murder of a young woman in San Francisco last week tragically illustrates that the politicization of the immigration debate has now swamped even common-sense efforts to protect public safety," Cotton said in a statement. "It is unacceptable that cities would issue ordinances that explicitly aim to frustrate federal immigration laws that are supposed to keep illegal immigrant felons off the streets.  U.S. taxpayers shouldn't be expected to support such misguided local policies that put their safety in jeopardy. No matter their political affiliation, local officials should support the rule of law and protect the safety of all Americans." 

In March, the Obama administration's top immigration official announced opposition to cracking down on sanctuary cities, calling such measures "highly counterproductive." As Stephen Dinan of the Washington Times reported at the time: 

The administration’s deportation chief backtracked Friday, just a day after she pleaded with Congress to pass laws cracking down on so-called “sanctuary” cities and states — a stance that appeared to put her at odds with her boss, President Obama. Immigration and Customs Enforcement Director Sarah Saldana, who has been on the job less than 90 days, told Congress she would welcome new laws to crack down on states and localities that refuse to cooperate with her agents who are trying to apprehend and deport illegal immigrants. “Thank you, Amen,” she said Thursday when asked if she would support Congress passing a law insisting local officials cooperate. Her remarks drew fire from immigrant-rights advocates, and on Friday she had to issue a new statement saying she does not, in fact, want to see Congress pass any new crackdown laws. “Any effort at federal legislation now to mandate state and local law enforcement’s compliance with ICE detainers will, in our view, be a highly counterproductive step and lead to more resistance and less cooperation in our overall efforts to promote public safety,” she said in an effort to walk back her previous statement to Congress.