Employers and employees often face frustrations when trying to determine the identity of persons who engage in anonymous acts of harassment in the workplace. These acts can involve notes, graffiti, telephone messages or other acts intended to intimidate and harass employees based on race, gender or other protected classifications. Federal law and practical issues limit employers’ ability to investigate these circumstances through measures such as polygraph exams. In many situations, employers are simply unable to identify the source of such harassing behavior or to take effective measures to end it.

Last week, the Fourth Circuit Court of Appeals (which includes North Carolina and South Carolina) told an employer that its efforts to stop anonymous harassment of an employee were simply inadequate as a matter of law. In Pryor v. United Air Lines, Inc., the plaintiff was an African-American flight attendant. She discovered in her company mailbox a racist and threatening paper note that she interpreted as a death threat against her and other black employees. Over the past several years, African-American employees had been the target of several other instances of racist rumors and anonymous behavior at this location. She reported the threat to her supervisor, who passed it along to airport administration instead of sending it to United for investigation and response.

Airport administration made initial efforts to determine the source of the note, but dropped the matter once this made no progress. United security eventually became aware of the complaint, but did not interview employees or attempt to collect forensic evidence such as fingerprints. When no one from United informed her of the progress of the investigation, the plaintiff filed a police complaint. The plaintiff claimed that United gave grudging cooperation to the police in their investigation of the matter. At the end of its investigation, United sent an email to employees at the airport asking them to report knowledge of any harassing activities.

Several months later, the plaintiff along with nine other United employees received a nearly identical racist death threat. Again, United had a tepid response to the incident. The company had not installed surveillance cameras in the mailroom between the two incidents, and no fingerprints were taken. United eventually installed cameras and began collecting employee fingerprints to use in the event of future occurrences. The plaintiff sued, claiming a hostile and offensive working environment due to her race. The district court dismissed the complaint, finding that the employer could not be held liable under Title VII for anonymous threats.

On appeal, the Fourth Circuit reversed this decision, remanding the matter for trial. In its decision, the court concluded that the harassing activity can be attributed to United based on its inadequate response to the matter. The racist behavior was clearly severe and pervasive. It was repeated over time, involved death threats and occurred within a supposedly secure area of the airport. The Fourth Circuit noted that employers have unique challenges when facing instances of anonymous harassment. However, the court concluded that in such situations, the employer must act reasonably to investigate the matter and protect the victims.

In this case, United failed to meet its obligation in multiple ways. Supervisors failed to follow company policy. It failed to conduct a prompt and thorough investigation. United did not collect forensic evidence or install surveillance equipment. The company did not report the matter to the police or adequately cooperate with the police investigation. It also failed to keep the plaintiff informed of the progress of its review of the matter.

The Fourth Circuit made clear that its opinion was not based on United’s failure to catch the perpetrator. Employers can act reasonably in response to anonymous complaints and still remain unable to identify or stop the source of the behavior. However, as this case makes clear, the fact that the source of the harassing behavior is not known in no way relieves the employer of its legal obligation under Title VII to promptly and thoroughly investigate the matter using all tools at its disposal. At a minimum, employers that learn of similar behavior should immediately report the matter to law enforcement authorities. Failure to take adequate measures in response