FORTUNE — Remember that time the government shut down for 16 days in October? Federal employees who were deemed “essential” and still had to work during the shutdown certainly do.
A lawsuit filed against the U.S. government seeking so-called liquidated damages is gaining steam, with more than 1,000 workers joining the suit last week.
The plaintiffs in this case — employees who worked during the shutdown that started on Oct. 1 but weren’t paid until after it ended on Oct. 16 — say that the Fair Labor Standards Act requires that workers receive at least minimum wage and overtime pay on their regularly scheduled paydays. For example, workers only received a partial paycheck for the Sept. 22 – Oct. 5 pay period and got the rest once the government reopened.
The lawsuit, originally filed in late October on behalf of five Bureau of Prisons employees, says that the essential workers are entitled to liquidated damages, which in this case are the minimum wages and overtime pay that they did not receive on time. Even though the employees eventually collected that money, under the FLSA, they are entitled to receive additional pay as damages, says Heidi Burakiewicz, a lawyer for the plaintiffs. That means the amount of money each worker could receive varies depending on how many hours a person worked, if that person worked overtime, and the rate of pay.
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“The Fair Labor Standards Act is meant to protect workers,” Burakiewicz says. “It’s important that if you do an honest day’s work you can depend on the fact that you’ll get paid on time so you can pay your own bills.”
The government has not yet issued a response in the case.
In addition to adding 1,017 employees to the lawsuit, Burakiewicz’s law firm Mehri & Skalet also asked the U.S. Court of Federal Claims to conditionally certify the “essential” federal workers as a class and send a notice about the lawsuit to the 1.3 million federal employees who worked during the shutdown and potentially could join the case. Those who are already on board have heard about the lawsuit only through word of mouth, Burakiewicz says.
The first real test of the lawsuit will come at an oral hearing on the conditional class certification next month and when the judge later rules on the issue.
To Burakiewicz’s knowledge, there were no similar lawsuits filed after past shutdowns — the federal government closed three separate times in the 1990s — but that doesn’t detract from the worthiness of this case. During the shutdown, Burakiewicz says, it seemed as if Congress was not concerned about how delayed paychecks would affect the lives of federal employees. “[The workers] incurred late fees; it hurt their credit,” she says. But even getting damages, she says, won’t fix all that.