Older workers could soon find it easier to prove they've run into age discrimination on the job.

The House Education and Labor Committee voted on Tuesday to approve the Protecting Older Workers Against Discrimination Act (POWADA), introduced by Sens. Chuck Grassley, a Republican from Iowa; and Bob Casey, a Democrat from Pennsylvania.

"The legislation makes Congress' intent clear that discrimination in the workplace – against older workers or others – is never acceptable," said Nancy LeaMond, AARP executive vice president and chief advocacy and engagement officer. AARP is an advocacy group for older Americans.

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The bill, which moves next to the full House and then the Senate, would reverse a 2009 Supreme Court decision, Gross v. FBL Financial Services, which required workers to prove that their age was the main factor in an employer's decision to discipline, fire or not hire them.

Jack Gross sued FBL Financial Services, claiming that the company violated the Age Discrimination in Employment Act of 1967 when it demoted him, at least in part, because of his age. He was 54 at the time. The court ruled that while Gross was able to show that age was one factor in his employer's decision, he failed to show that it was the sole reason.

Advocates say the decision sent a message to employers that some age discrimination was fine.