STORM LAKE, Iowa | Tyson Foods has asked for a new trial in a case in which workers at its Storm Lake pork plant were awarded $5.8 million.

In a brief filed last week in U.S. District Court in Sioux City, Tyson lawyers said a new trial is needed to address both liability and damages issues. The food company said a new trial would help determine which of the workers included in the class action lawsuit are entitled to a share of the verdict.

Several methods of disbursing the money have been proposed by the workers, Tyson said, but none of them ensure that only people who deserve a share get it.

“As a result, the verdict cannot stand,” Tyson said in its brief.

In March, the U.S. Supreme Court voted 6-2 to reject new limits Tyson asked to have imposed on the ability of workers to band together to challenge pay and workplace issues.

Peg Bouaphakeo and other Tyson Storm Lake workers sued in 2007 to collect back pay for the time they spent putting on and taking off protective work clothes and equipment before wielding sharp knives in slaughtering hogs and processing the animals.

A federal jury in Sioux City awarded $5.8 million in overtime and damages for more than 3,000 workers. The lower court decision was upheld by the 8th Circuit Court of Appeals in 2014.

Because Tyson did not keep records, the workers tried to prove the damages based on an expert witness’ statistical inferences of how long it took the workers to get ready for their jobs on the plant’s slaughter or “kill” floor and the processing or “fabrication” floor.

Tyson challenged the means by which the class-action status was granted. The questions before the court were whether statistics should have been allowed to determine damages for all employees. Rather than base the damages on the average amount of time it took employees to get ready, the award should have been assessed individually for each plaintiff, Tyson argued.