I'm also in NY, on Long Island, my psych instructor was talking about this the other day - she said how often a bunch of policemen will drag an agitated patient into her psych hospital and leave him to her care - just her, by her lone little self. If that patient hauled off and hit the cops, he'd go to jail, but if he hit her, probably nothing.
I can understand the potential for violence with psych patients, but the idea that a patient on a non-psych floor could beat up a nurse and not be punished is ridiculous - walking thru the hospital doors does not excuse you from the laws of society.