The federal courts of appeals have long disagreed about what to do in “mixed-motive” discrimination cases – that is, cases in which an adverse employment action (such as a firing, demotion, or failure to hire) occurs for both legitimate and illegitimate reasons. In its decision in Desert Palace, Inc. v. Costa, the Supreme Court provided some much needed clarity on this issue.

The bottom line of the Court's decision is this: plaintiffs do not need a “smoking gun” to bring a mixed-motive discrimination case. Instead, less obvious evidence of discrimination can also suffice. That's welcome news for discrimination victims. Employment decisions are rarely made for a single reason. If discrimination enters into the mix, plaintiffs should have the opportunity to sue without facing any special, higher standards for the proof they must use. The Court rightly recognized Congress's intent on this point.

THE FACTS OF THE DESERT PALACE CASE

The case was brought by Catherina Costa, who was fired from her job as a warehouse worker and heavy equipment operator, the only woman in that job. She sued under Title VII of the Civil Rights Act of 1964. Costa alleged that her firing was an act of sex discrimination. After a physical altercation with a male coworker, she was fired. He, in contrast, received only a short suspension. On the basis of this disparity in discipline, other alleged acts of discrimination, and claims of sexual harassment, Costa sued.

Her employer, however, points to Costa's documented history of disciplinary problems. It says the firing was its response to this history; she was a “problem” employee, it argues. Both Costa and her employer may be telling the truth – both Costa's history on the job (legitimate consideration) and her gender (illegitimate consideration) may have played a role in her firing.

Should the jury get to decide this case? If a jury believes both sides, what should it do? How good does Costa's evidence of sex discrimination have to be for her to prevail on a theory of mixed-motive discrimination? These are important legal questions on which the judge must instruct the jury. Unsurprisingly, the related question of exactly what form the jury instruction in a mixed-motive case should take has been intensely controversial.