June 18 (Bloomberg) -- A divided U.S. Supreme Court made it harder for workers to win age-discrimination suits, overturning a $47,000 award to a demoted FBL Financial Group Inc. employee.

The justices, voting 5-4 along ideological lines, said workers must show that age discrimination was the cause of a demotion or other adverse employment decision, and not just one of several factors that played a role.

The ruling means that workers must meet a tougher standard under the Age Discrimination in Employment Act than they do when alleging race or gender discrimination under a different law, known as Title VII.

“Unlike Title VII, the ADEA’s text does not provide that a plaintiff may establish discrimination by showing that age was simply a motivating factor,” Justice Clarence Thomas wrote for the majority. He said workers had to show that the employer’s action wouldn’t have occurred in the absence of age bias.

In dissent, Justice John Paul Stevens called the decision “unnecessary lawmaking” that went beyond the issues the court agreed to consider in the case. He said the majority’s interpretation ran contrary to a 1989 Supreme Court decision involving Title VII and a 1991 law enacted by Congress.

Chief Justice John Roberts and Justices Antonin Scalia, Anthony Kennedy and Samuel Alito joined Thomas. Justices Stephen Breyer, David Souter and Ruth Bader Ginsburg also dissented.

Business Victory

Business advocates hailed the ruling, saying it will limit a growing category of litigation. Workers filed more than 24,000 age-discrimination complaints with the Equal Employment Opportunity Commission in fiscal 2008.

Letting cases proceed under a so-called mixed motive theory “would have exposed employers to countless allegations of discrimination,” the National Federation of Independent Business said in a statement.

Senate Judiciary Committee Chairman Patrick Leahy, a Vermont Democrat, likened the decision to a 2004 pay discrimination ruling issued by the same five-justice majority. Congress reversed that ruling this year with a law named after Lilly Ledbetter, the Alabama worker whose case prompted the high court ruling.

“This overreaching by a narrow majority of the court will have a detrimental effect on all Americans and their families,” Leahy said in a statement.

Statutory Language

The ADEA makes it illegal for an employer to take an adverse action against a worker “because of such individual’s age.” Title VII contains similar language.

Thomas said Congress amended Title VII in 1991 to explicitly authorize discrimination claims when an improper consideration was a “motivating factor.”

“We cannot ignore Congress’ decision to amend Title VII’s relevant provisions but not to make similar changes to the ADEA,” Thomas wrote.

The high court case concerned Jack Gross, who began working for FBL, an Iowa-based insurance and financial services company, in 1971. In 2003, at age 54, Gross was reassigned from his post as claims administration director to the position of claims project coordinator. A jury concluded the demotion cost Gross more than $43,000 in salary and stock options.

FBL said that the new assignment was part of a broader reorganization and that superiors thought the new assignment was a better fit for Gross’s strengths.

The case is Gross v. FBL Financial Services, 08-441.

To contact the reporter on this story: Greg Stohr in Washington at gstohr@bloomberg.net.

Last Updated: June 18, 2009 15:33 EDT