WASHINGTON — Driver’s license photographs and biographic information of most Americans would be accessible through an expanded Department of Homeland Security nationwide computer network if the immigration legislation pending before the Senate becomes law.

The proposed expansion is part of an effort to crack down on illegal immigration by requiring all employers to confirm the identity and legal status of any new workers by tapping into a Homeland Security Department system called E-Verify, which is now used voluntarily by about 7 percent of employers in the United States.

But the proposal already faces objections from some civil liberties lawyers and certain members of Congress, who worry about the potential for another sprawling data network that could ultimately be the equivalent of a national ID system.

The questions are being raised while a debate takes places over access to domestic phone records and Internet files of foreigners.