Homeland Security Secretary Michael Chertoff told a House panel that his agency will enforce the Basic Pilot Program that requires businesses to check the legal status of new employees.
Under the program, employers are required to match Social Security numbers and information in Homeland Security Department databases to weed out illegal aliens.
Chertoff told the House Homeland Security Committee on Wednesday: “I certainly wouldn't tolerate interference" by cities who attempt to block the program.
“We're exploring our legal options,” he said. “I intend to take as vigorous legal action as the law allows to prevent that from happening, prevent that kind of interference."
Chertoff stopped short of threatening so-called "sanctuary cities" – which ban police and other city employees from asking about a person’s immigration status – by withholding government funding, the Washington Times reported.
"I don't know that I have the authority to cut off all Homeland Security funds if I disagree with the city's policy on immigration," he said.
"And of course, I have to say the consequence of that might be to put the citizens at risk in the event of a natural disaster.
“I don't want to put people's lives at risk, but I do think where the law gives me the power to prevent anybody from interfering with our activities, we will use the law to prevent that interference.”
“Sanctuary cities" include New York, San Francisco, Dallas, Minneapolis, Miami, Denver, Baltimore and Washington, D.C.
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