When he got to the psych unit, he was so adorable, so normal, they released him, telling me they couldn't find anything wrong with him.
After attacking me for a second time, hitting and busting down a caregiver's door, and 40 caregivers later, I had to threaten the psychiatrist with a lawsuit if they released him and he came home and hurt anyone. They finally held him 2 weeks ("5250") and reported that he couldn't learn very well and that his memory was slipping.
It was so intermittent; he was able to act normal most of the time, and could still hide his life-long temper tantrums. He was a master at hiding that part of himself to anyone outside the immediate family, and that did not change. The professionals never saw it and thought I was a horrible daughter for not being compassionate about my "sweet slightly-demented" father.