In a 5-4 decision announced today, the U.S. Supreme Court held in University of Texas Southwestern Medical Center v. Nassar, 570 U.S. ___ (2013) that Title VII retaliation claims must be proved using a “but-for” causation standard as opposed to the lower threshold “motivating factor” standard. Under the standard of causation adopted in today’s opinion, a claimant must prove “that the unlawful retaliation would not have occurred in the absence of the alleged wrongful action or actions of the employer.” The opinion is a watershed development that represents a seismic shift in the Court’s approach to establishing a retaliation claim, particularly given that the Court’s recent opinions in this arena have expanded the reach of retaliation claims.

Writing for the majority, Justice Kennedy rejected the complainant’s argument that he only needed to show his prior protected activity was a “motivating factor” in the employer’s decision to not re-hire him. The Court rested its decision on a plain reading of Title VII—i.e., Title VII will be violated “when the complaining party demonstrates that race, color, religion, sex, or national origin was a motivating factor for any employment practice, even though other factors also motivated the practice.” The Court concluded that Congress deliberately omitted retaliation from the discriminatory acts identified in the motivating factor provision of the 1991 amendments to Title VII.

In the absence of a specific statutory pronouncement of the “motivating factor” standard, the Court followed its reasoning in the 2009 decision Gross v. FBL Financial Services, Inc., which held that “but-for” causation is the appropriate standard for ADEA retaliation claims. In reaching this conclusion, the Court rejected the argument that retaliation is implicitly covered by a statutory ban on discrimination. The Court acknowledged it has previously applied such reasoning in the context of broadly-worded anti-discrimination statutes, but found the reasoning to be “inappropriate in the context of a statute as precise, complex, and exhaustive as Title VII.” The Court also rejected arguments that the easier “motivating factor” standard should be adopted because it is consistent with the EEOC’s interpretation of the statute, as expressed in published guidance on the question. Because the EEOC’s interpretation did not specifically address or reconcile the omission of retaliation from the 1991 amendments and relied on circular reasoning, the Court held it was not sufficiently persuasive to warrant deference.

While the dissent voiced strong objection to the application of two different standards to claims of discrimination and retaliation under the same law, the majority maintained that such a distinction is not only mandated by the text of the statute, but also critical to the “fair and responsible allocation of resources in the judicial and litigation systems.” Citing the upsurge in retaliation claims and the potential for abuse of a lower causation standard, the Court provided the example of an employee who makes a frivolous claim of discrimination to forestall a lawful and justified employment action. According to the Court, a lower causation standard would make it difficult for employers to combat these frivolous claims at the summary judgment stage and, consequently, would divert judicial and administrative resources from legitimate claims of discrimination.

Although the Court’s adoption in Nassar of the more exacting causation standard may help employers defeat certain retaliation claims at summary judgment, it does not eliminate—or even reduce—employers’ need to guard against retaliation claims through sound policies, prompt investigations and supervisory training.