In its 2009 Gross decision, the U.S. Supreme Court determined that plaintiffs seeking recovery under the Age Discrimination in Employment Act must prove that "but-for" the alleged age discrimination, the employer would not have taken the adverse action that is the subject of the complaint. This differs from the usual burden of proof for Title VII discrimination claims, which only requires that the plaintiff demonstrate that discrimination was a motivating factor for the adverse decision.
 
Last week, the Supreme Court agreed to review a Fifth Circuit decision that applied this lower "mixed motive" standard to a retaliation claim under Title VII. Univ. of Texas Southwestern Med. Ctr. v. Nassar involved a faculty member who alleged that his former employer attempted to block him from finding new employment after he filed race and religion discrimination claims. The Fifth Circuit concluded that the mixed motive standard applies to the retaliation claim.

Title VII's anti-retaliation language was the basis for similar provisions in a number of federal civil rights laws. If the Court concludes that the higher "but-for" standard applies, this could make employment retaliation claims much harder for plaintiffs to prove, and significantly improve employers' chances of obtaining summary judgment dismissal. The Supreme Court has not scheduled oral arguments on this case, but a decision may be released by the end of the current term in June, or at the beginning of the next term in October.