ALBANY – A law intended to purge fraudulent names from New York’s driver-registration rolls is forcing thousands of undocumented workers underground and increasing the likelihood of hit-and-run accidents in the state, a Brooklyn lawmaker says.

A Sunset Park Democrat, Felix Ortiz, is now asking legislators to give undocumented immigrants in New York the right to drive without verifiable identification.

The proposal is welcomed by immigrant-rights activists but is likely to face stiff resistance from lawmakers leery of appearing soft on terror. The proposal was issued on a day when the director of the state’s Office of Homeland Security, James McMahon, updated lawmakers in Albany on the condition of New York’s anti-terror efforts.

Mr. Ortiz made the proposal just yards away from the hearing room where Mr. McMahon delivered his testimony. The Assemblyman – who suggested last year that the state impose a 1% tax on junk food and video games to finance anti-obesity programs for children – was joined by a trucker from Poughkeepsie, Santiago Sanchez. Mr. Sanchez, 32, said he would have fled the scene of an accident had he been forced to verify his identify before obtaining legal working status last month.

Mr. Ortiz said a year-old effort by the Department of Motor Vehicles to identify drivers with fraudulent licenses – and potential terrorists – is terrorizing illegal immigrants like Mr. Sanchez who depend on their cars to travel to and from work. He estimated that more than 500,000 people in the state could be affected by the purge.

Since last January, the DMV has identified more than 275,000 licensed drivers with questionable credentials. Each has received a letter requesting that they either verify their identities or supply the department with a letter from the Social Security Administration explaining why they do not have a valid Social Security number.

A spokesman for the department said the effort has resulted in 1,700 non-commercial and 4,800 commercial suspensions over the past several months. In one case, the spokesman, Joe Picchi, said the department discovered 57 residents using the same Social Security number for purposes of identification.

“We’re not targeting one specific group,” Mr. Picchi said. “We’re trying to make sure people are who they say they are.”

The scrutiny of driver’s licenses intensified four years ago when it was discovered that seven of the terrorists who attacked American sites on September 11, 2001, had moved around the country using fraudulent Virginia licenses. Virginia did not require applicants to provide verifiable identification at the time.

In New York, valid Social Security cards have been required as part of the license-application process since 2000. But the state lacked a reliable way to check the cards against federal records, Mr. Picchi said, until it installed three years ago a system that matched state and federal records.

Over the past year, officials at the department have praised the new program as a potent anti-terror tool. In testimony before legislators here in August, the department’s commissioner, Raymond Martinez, said the new tool does not target illegal immigrants. He said the department was working with the Social Security Administration to ensure “that these individuals could still be licensed.”

Not all states require verifiable identification as part of the licensing process. Three years ago, New Mexico and South Carolina passed laws lifting the requirement of a Social Security number. Nine other states have since followed suit. Immigrant-rights organizations and labor groups are pushing for still more states to drop the requirement.

As an alternative to Social Security numbers, Mr. Ortiz is suggesting the use of Individual Taxpayer Identification Numbers. The Internal Revenue Service issues so-called “ITINs” to persons who do not qualify for Social Security numbers to pay taxes on their income. But the DMV has argued against their use because, it says, they are not subject to the same rigorous verification standards as Social Security numbers.

Mr. Ortiz said the safety of New York’s drivers is being compromised by the requirement. He also said the state is losing out on $90 million annually in lost registration and license fees from residents who will now avoid obtaining a license altogether.

“There is nothing in state law that says you need to be a legal immigrant to get a state license,” Mr. Ortiz said. “Eleven states allow people to use ITINs. I don’t see why New York can’t.”