On June 24, 2013, the United States Supreme Court decided University of Texas Southwestern Medical Center v. Nassar, in which the Court held that claims of retaliation must be proved using a “but for” standard as opposed to the seemingly lower “motivating factor” standard of causation.
The plaintiff had argued that in order to prevail on his claim of retaliation, he had to show that his engaging in protected activity was a motivating factor in his termination. The motivating factor standard, which applies to claims of status discrimination (e.g., sex, race, religion, national origin and disability), provides that to prevail on an employment discrimination claim, an employee need only “show that the motive to discriminate was one of the employer’s motives, even if the employer also had other, lawful motives for the decision.”
Based upon its review of the language of Title VII, the Supreme Court stated that the motivating factor standard did not apply to claims of retaliation, and that, instead, traditional principles of but-for causation applied.