A new rule requiring government contractors to certify the employment eligibility of their workers using the Homeland Security Department's E-Verify system could be delayed for a fifth time.

Five industry groups said they plan to appeal a federal court ruling that struck down their attempt to legally halt implementation of the rule. That ruling was made by the U.S. District Court for Maryland on Aug. 31. On Sept. 1, the industry groups filed a motion to prevent the rule's implementation, now scheduled for Sept. 8.

The plaintiffs — the U.S. Chamber of Commerce, Associated Builders and Contractors, the Society for Human Resource Management, the American Council on International Personnel and the HR Policy Association — argue that going forward with the rule while the case is under appeal would cause "irreparable harm" to government contractors. Contractors would be forced to incur the costs of screening new and existing employees in the E-Verify system without assurance the mandate is legal, the motion said.

Without a delay, some employers could be forced to recertify the employment status of tens of thousands of employees, which would be both a logistical and financial burden, said an attorney for the U.S. Chamber of Commerce who asked not to be named because he is not the lead attorney on the case.

The final rule published in the Federal Register on Nov. 14, 2008, estimated the combined cost to government, contractors and subcontractors at $246 million for the first year it is in effect and $1.1 billion for the first 10 years.

Citizenship and Immigration Services, which runs the E-Verify system, has no plans to delay the rule's implementation unless ordered by the court, said CIS spokesman William Wright. CIS delayed the rule four times as a result of the case. It was originally supposed to go into effect Jan. 14.

Last week, Maryland District Court Judge Alexander Williams ruled the new procurement rule didn't violate the statute authorizing E-Verify, which specifically prohibits the government from making the system mandatory. The procurement rule is legal because "the decision to be a government contractor is voluntary," Williams wrote. "Nobody has a right to be a government contractor."

Associated Builders and Contractors sees it differently, said Bob Hirsch, director of legal and regulatory affairs for the organization. "It's not as voluntary as it has been made out to be," Hirsch said. Some contractors have been doing business exclusively with the government for a decade or more and are now being forced to reverify the employment of all of their employees or risk their livelihood, he said.

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