An employer’s liability for co-worker harassment exists if the employer knew or should have known of the harassment and failed to take prompt remedial action. In other words, an employer may be liable for non-supervisory co-worker harassment if the employer was negligent in failing to discover the co-worker harassment or in responding to a report of harassment. Knowledge of a sexually hostile work environment arises when a "management level employee" obtains enough information to raise the probability of sexual harassment in the mind of a reasonable employer.

In its decision in Huston v. The Proctor & Gamble Paper Products Corp., the Third Circuit Court of Appeals concluded that an employee’s knowledge of allegations of co-worker sexual harassment may typically be imputed to the employer in two circumstances:

  1. "where the employee is sufficiently senior in the employer’s governing hierarchy, or otherwise in a position of administrative responsibility over employees under him, such as a departmental or plant manager, so that such knowledge is important to the employee’s general managerial duties. In this case, the employee usually has the authority to act on behalf of the employer to stop the harassment, for example, by disciplining employees or by changing their employment status or work assignments. The employee’s knowledge of sexual harassment is then imputed to the employer because it is significant to the employee’s general mandate to manage employer resources, including humanresources;" or
  2. "where the employee is specifically employed to deal with sexual harassment. Typicallysuch an employee will be part of the employer’s human resources, personnel, or employee relations group or department. Often an employer will designate a human resources manager as a point person for receiving complaints of harassment. In this circumstance, employee knowledge is imputed to the employer based on the specific mandate from the employer to respond to and report on sexual harassment."

The court went on to clarify that mere supervisory authority over the performance of work assignments by other co-workers is not, by itself, sufficient to qualify an employee for management level status unless the worker has  a mandate generally to regulate the workplace environment. This reasonably bright line test should help employers to avoid allegations of constructive knowledge of workplace problems; provided, job descriptions clearly define the employee’s job duties. Employers should examine generalized policy statements that create a "duty" to report workplace harassment or mistreatment.