Edmund Gernannt suffered from Alzheimer’s disease. He was involuntarily committed to the acute geriatric psychiatric unit of a hospital. Gernannt was known to behave violently toward staff, sometimes trying to hit the nurses attending him. One day Gernannt tried to use the fire exit to leave the psychiatric unit. One nurse tried to bring Gernannt back to his room, but he began hitting her. The unit’s head nurse, Mary Berberian (plaintiff), was on duty. She was familiar with Gernannt’s history of agitation and aggression. Berberian reached out her hand to Gernannt. He grabbed Berberian’s hand and pushed her back. Berberian fell, breaking her leg. Berberian sued Gernannt’s guardian, Diane Lynn (defendant) for negligence. At trial, Berberian requested that the jury be instructed to hold Gernannt to a duty of care for a reasonable man. The trial court denied this request, and instead instructed the jury to hold Gernannt to a duty of care for a reasonable man with Alzheimer’s dementia. The jury found in favor of Lynn. Berberian appealed, arguing that the standard of care applied to Gernannt should not be based on his mental capacity. The court of appeals affirmed. Berberian appealed.