A national biometric database is hidden in the 800-page immigration legislation being proposed in the Senate, Wired.com reports.
The biometric database is a tool run by the Department of Homeland Security. It has the name, age, Social Security number and photograph of everyone in the country with a driver's license or state-issued photo ID.
Employers would be required to look up every new hire to confirm that they match their photo. Experts say the goal is to curb the hiring of undocumented immigrants.
But privacy groups say this could be the first step towards a national identification system.
"It starts to change the relationship between the citizen and state, you do have to get permission to do things," Wired.com quoted Chris Calabrese, a congressional lobbyist with the American Civil Liberties Union. "More fundamentally, it could be the start of keeping a record of all things."
David Bier, an analyst with the Competitive Enterprise Institute, warned, "The most worrying aspect is that this creates a principle of permission basically to do certain activities and it can be used to restrict activities. It's like a national ID system without the card."
Presently, the debate in the Senate Judiciary Committee focuses on legalization for unauthorized immigrants. But critics say historically such limitations don't last. The national database will inevitably affect all Americans.
The committee debate is scheduled to resume May 14.