Richard Wolf

USA TODAY

WASHINGTON — The Supreme Court ruled Tuesday that some class action lawsuits filed by consumers or workers can be based on statistical averages rather than actual data.

The 6-2 decision was another unlikely defeat for business interests at the usually business-friendly court. But it does not conflict with the court's 2011 ruling in an employment discrimination case against Walmart that denied "trial by formula." Instead, it was a narrow victory for workers at an Iowa pork processing plant seeking overtime pay for time spent putting on and removing sanitary and protective gear.

"The court would reach too far were it to establish general rules governing the use of statistical evidence, or so-called representative evidence, in all class action cases," Justice Anthony Kennedy wrote.

And the victory may prove to be fleeting. Chief Justice John Roberts joined Kennedy and the court's four liberal members in the majority, but he wrote separately with a warning: Unless the original federal district court that handled the case can determine which Tysons employees worked more than 40 hours a week and are therefore eligible for part of the $5.8 million jury award, "that award cannot stand."

"I am not convinced that the district court will be able to devise a means of distributing the aggregate award only to injured class members," Roberts said.

Justices Clarence Thomas and Samuel Alito dissented, as they have done frequently in divided cases and orders since last month's death of Justice Antonin Scalia. Thomas said the court's precedents prohibit class actions "when an important element of liability depends on facts that vary among individual class members."

The line workers' victory was presaged during oral argument in November. Five justices expressed sympathy then for the workers' argument that since Tyson Foods kept no records of time spent preparing for slaughter and processing assembly lines, they could rely on a 69-year-old Supreme Court precedent permitting such averaging.

The workers' challenge was the third case to reach the court last fall pitting workers or consumers against companies in what often are multi-million dollar battles over class action lawsuits. Workers and consumers depend on such collaborations; businesses say they gloss over different grievances and often grant awards to people who were unaffected.

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In each case, the justices agreed to hear petitions from companies seeking to overturn lower court rulings that allowed such lawsuits to proceed. But Kennedy and the court's four liberal justices said during oral arguments that Tyson Foods failed to make a convincing argument against averaging workers' preparation time.

Justices tilt toward workers in dressing time fight

Tyson Foods, one of the world's leading producers of meat and poultry, was trying to knock down a class-action lawsuit filed on behalf of more than 3,300 current and former plant workers seeking overtime pay. Its claim that the workers don't share enough common traits to sue as a class followed similar cases heard in October and November in which companies argued that consumers could not prove any injury or had been offered complete restitution. Now two of the three cases have been decided in favor of workers or consumers.

Consumer and labor groups had feared the court would follow its past example and rule for the companies, as it did in the Walmart pay discrimination case filed on behalf of 1.5 million female employees. In 2013, the justices also denied Comcast's cable subscribers the right to sue as a class against alleged antitrust activities.

The common issue connecting this term's cases is what type of injury rises to the level of a lawsuit — in particular, one in which hundreds or thousands of people can join together. The question is important, because while plaintiffs stand to gain from jury awards that can reach into the millions or even billions of dollars, companies face potentially ruinous verdicts.

Tyson Foods was found liable for $5.8 million in damages for refusing to pay workers overtime at its Storm Lake, Iowa, processing plant for the minutes they spend preparing for and leaving the assembly line. Similar cases pending before the court involve a $187 million verdict against Walmart and a $1.1 billion verdict against Dow Chemical.

Liberal interest groups had argued that a ruling against the workers could make it more difficult to prove race or gender discrimination or price-fixing based on the same type of statistical analyses.

In winning lower court victories, attorneys for Tyson employees contended that the company had "plant-wide policies" against overtime pay for putting on and taking off uniforms and walking to and from work stations. Because the company did not keep time records for those activities, the employees cited studies estimating statistical averages, then computed those estimates into dollars.

Company lawyers argued against that model, contending the Iowa workers had 420 different jobs and therefore could not have suffered the same injury as a result of the pay policy. Hundreds of them had no claim at all, the company said.