Swift Transportation is one of the largest trucking carriers in the United States. This Phoenix, Arizona based company is now facing a lawsuit for allegedly shorting drivers millions in mileage-based pay for decades.

An initial lawsuit was filed against the trucking company in 2004. The suit claimed that the transportation corporation underpaid tens of thousands of drivers, equating to at least half a billion dollars. The company blamed their software for miscalculating drivers’ miles.

Plaintiffs’ attorney Leonard Aragon commented, “Despite what Swift has been saying for years, they have the means to properly pay their drivers if they want to.”

He continued,

“If you’re going to promise people that you’re going to pay them per mile, and you have the means to figure out how many miles they drove, then the natural result would be that they would get paid per mile they drive.”

In 2006, a motion was filed to have the lawsuit certified as a class action suit. A Superior Court judge denied this ruling. Since then, the case has visited the the Arizona Supreme Court and the  Court of Appeals twice.

On Tuesday, the Court of Appeals overturned a 2015 ruling that rescinded a previous approval of class-action status. Because Swift employee drivers and independents had contracts with Swift dating back to January 30, 1998, the number of employees affected is staggering. AZ Central reported that with its new class-action status, this decade-old case filed by one trucker can act on behalf of 80,000 employees across the country.

Karen Rasmussen, president and CEO of the Arizona Trucking Association, commented,

“You don’t want your truck drivers driving past their allotted hours from a legal perspective and from a fatigue perspective. You got the deep pockets. You got the liability if something happens.”

Although Swift Transportation wanted to examine cases individually, the Court of Appeals explained that class action status was valid. The court stated that the trucking company failed to inform drivers that its payment method was less accurate than other available methods.

Swift Transportation failed to comment on the pending lawsuit.