June 18, 2209, in a 5-4 decision, the U.S. Supreme Court held that an
employee alleging a disparate treatment claim under the Age Discrimination
in Employment Act (ADEA) must prove that age was the “but for”
cause of the challenged adverse employment action. Justice Clarence
Thomas, writing for the majority, ruled that even where the employee has
produced evidence that age was one motivating factor in that decision the
burden of persuasion does not shift to the employer to show that it would
have taken the action without regard to age. Gross v. FBL Financial
Services, Inc., No. 08-441, U.S. Supreme Court (June 18, 2009).
