A care home worker was alone when she was strangled by a mentally ill patient in Feb. 2011. The patient was charged with manslaughter, but found mentally unfit to stand trial. A risk assessment done on him after he attacked another female staff member warned of the danger to anyone caring for him. And a preliminary report by Occupational Health and Safety said the Persons With Developmental Disabilities Board didn’t warn the worker or the home that he was violent and dangerous. But an Alberta Justice spokeswoman just said there isn’t enough evidence to recommend charges.