In Anderson v. Oklahoma State University Board of Regents, No. 08-6249, 2009 WL 2488158 (10th Cir. Aug. 17, 2009), the United States Court of Appeals, Tenth Circuit, held that preferential treatment on the basis of a consensual romantic relationship between a supervisor and an employee is not gender-based discrimination. In Anderson, the plaintiff complained to his employer that he believed his supervisor was having an affair with a female employee. He claimed that after he reported the affair he was not included in managerial meetings and felt excluded from involvement in department matters. Subsequently, the plaintiff was terminated as part of a reduction-in-force (“RIF”). After his termination, the plaintiff alleged that he was terminated from his employment in violation of Title VII of the Civil Rights Act of 1964 (“Title VII”).

The district court ruled that the plaintiff’s action of complaining about his supervisor’s affair and the alleged favoritism the supervisor showed to that employee was not protected opposition to discrimination under Title VII. In affirming the district court’s decision, the Court of Appeals stated that “preferential treatment on the basis of a consensual romantic relationship between a supervisor and an employee is not gender-based discrimination.” The court reasoned that “Title VII’s reference to ‘sex’ means a class delineated by gender, rather than sexual affiliations.” Therefore, the court concluded that the plaintiff’s complaints about his supervisor’s affair and favoritism did not constitute opposition to an employment practice made unlawful by Title VII.