U.S. Sues Illinois to Let Employers Use Immigrant Databases.

The Bush administration sued the State of Illinois yesterday, hoping to block a new state law that bars employers from using a federal database to verify that immigrant job applicants are in the United States legally and are authorized to work.

With the suit, officials said, the administration is going on the offensive in the courts in response to cases intended to stall a crackdown on illegal immigration that the federal authorities announced last month.

“We will vigorously contest any effort to impede our enforcement measures,” the Homeland Security secretary, Michael Chertoff, said yesterday in a telephone interview.

The suit, brought by Mr. Chertoff’s department, seeks to stop Illinois from putting into effect a law that forbids employers from enrolling in the federal worker verification database program.

The program, formerly known as Basic Pilot, was renamed E-Verify last month.

Under the Illinois statute, the ban would remain until Washington certifies that the databases used to verify workers’ eligibility are 99 percent accurate.

Supporters of the law say the Social Security Administration and Homeland Security Department databases used to confirm eligibility are riddled with errors and could result in the denial of jobs to legal workers, including citizens.

The law, which passed with bipartisan support, was signed by Gov. Rod R. Blagojevich on Aug. 13 and is to take effect on Jan. 1.

Mr. Blagojevich, a Democrat, did not comment yesterday, because he reportedly had not had a chance to read the suit. A spokeswoman for him, Abby Ottenhoff, said he had signed the bill because he “concurred with the General Assembly that the system now leaves too much room for mistakes and abuse.”

Ms. Ottenhoff said lawmakers had determined the verification program had a 50 percent accuracy rate and was slow, taking up to 10 days to respond to employers.

The suit, filed in Federal District Court for the Central District of Illinois, argues that the state statute is unconstitutional because it pre-empts federal laws that established the worker verification program, beginning in 1996.

The program compares job applicants’ identity information against the Social Security and immigration databases. Illegal immigrants often present false names or Social Security numbers when seeking work.

The program, which functions in all states, remains voluntary for most employers. The suit says 22,200 employers are enrolled in the system, which handled 2.9 million inquiries from employers in the current fiscal year.

“We want to be sure that employers can participate without being punished by the state,” Mr. Chertoff said. “We don’t want them to be guinea pigs” in a legal test between conflicting federal and state laws.

With the defeat of a broad immigration bill in the Senate in June, Mr. Chertoff said, “Congress said, ‘We want you to enforce the law first,’ ” before measures could be considered to give legal status to illegal immigrants.

The Illinois law was supported by business and labor organizations. “We have no problem with the program, but the program needs to be accurate,” said Tim Bell of the Chicago Workers’ Collaborative, which helped pass the statute.

Immigration officials said they would begin a system today within the verification program to allow employers for the first time to compare applicants’ photographs against pictures in immigration agencies’ records.

Last month a federal judge in San Francisco temporarily held up a new federal rule that would have forced employers to dismiss illegal immigrants after 90 days