The Supreme Court has ruled that employees must do more than prove that age was a “motivating factor” in a adverse employment decision to prevail in lawsuits alleging age discrimination--they have the burden of proving that their age was the "but-for" cause of the employer’s decision.
The court rejected the argument that the ADEA allows a mixed-motive discrimination claim. A mixed-motive claim involves an allegation that the employee suffered an adverse employment action because of both permissible and impermissible considerations (that is, a protected characteristic was a motivating factor in the decision). Mixed-motive claims are allowed under the Title VII of the Civil Rights Act of 1964, which prohibits discrimination based on
an individual's race, color, religion, sex, or national origin.
The court said that under the Age Discrimination in Employment Act (ADEA), employees must prove by a preponderance of the evidence, that age was the “but-for” cause of the challenged adverse employment action.
“Unlike Title VII, which has been amended to explicitly authorize discrimination claims where an improper consideration was ‘a motivating factor' for the adverse action, the ADEA does not provide that a plaintiff may establish discrimination by showing that age was simply a motivating factor,” the court wrote.
The case (Gross v. FBL Financial Services, Inc.) involved a worker who alleged that an employer demoted him in violation of the ADEA.
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