A powerful Senate chairman on Friday demanded that $2 billion in police funding the Justice Department doles out be cut off from "sanctuary cities," claiming the designation led to the killing in San Francisco of Kathryn Steinle and is "potentially deadly to law-abiding American families."

Sen. Richard Shelby, chairman of the Senate Committee on Banking, Housing and Urban Affairs, made the demand to Attorney General Loretta Lynch in a two page letter. He is also chair of the appropriations subcommittee that oversees Justice spending.

"Any violent crime is tragic, but the fact that the senseless death in San Francisco arose directly from a 'sanctuary city' deliberately obstructing policies to remove illegal immigrants who have committed crimes is appalling and inexcusable," said Shelby. "I strongly believe that interfering with the routine coordination of federal law enforcement is intolerable and potentially deadly to law-abiding American families."

Kate Steinle and the man suspected in her death, Juan Francisco Lopez-Sanchez. Photos via AP

Sanctuary cities like San Francisco essentially don't cooperate with federal immigration officials when it comes to illegals in their cities. The Center for Immigration Studies said this week that there are at least 200 of the cities.

The alleged killer in San Francisco had been deported several times but the Feds were not contacted after his latest run-in with the law before shooting Steinle, 32.

"Municipalities that refuse to cooperate with federal immigration laws simply should not receive the Department of Justice's assistance funding," added the Alabama Republican. "The freedoms we enjoy – like strolling on a San Francisco pier with our children – are possible only when we are willing to enforce the federal laws that keep our families and our freedoms safe."

Sen. Rand Paul is introducing legislation that would cut off funding to the cities.

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com.