A nurse had worked on the maternity unit for six years before suffering a seizure at home. Her neurologist determined the seizure was related to fatigue, and indicated in a report to the hospital that a daytime-only position was absolutely necessary for this nurse.

   The hospital, however, had a policy, and the hospital's policy was part of the collective bargaining agreement with the nurses, that all nurses with less than fifteen-years seniority who worked on twenty-four hour units had to rotate shifts. This meant that nearly all maternity nurses had to work nights about one-third of the time.

   According to the U.S. Circuit Court of Appeals for the First Circuit, the Americans With Disabilities Act requires an employer to offer reasonable accommodation to an employee's disability. If an employer fails to offer reasonable accommodation, the employee can sue for disability discrimination.

   However, by definition, it is not reasonable accommodation for an employer to have to dispense with the essential functions of a disabled employee's job. In this context the court ruled that availability for night shift work is an essential function of a nurse's job on a unit that provides patient care around the clock.