I'm not sure about the policies for where you work but I work on a ward with mentally disturbed offenders - most of which have personality disorders. I was working when a staff member was physically assaulted in an unprovoked incident. The staff member was strongly encouraged to press charges for assault even though the possiblity of the pt being given any kind of sentence or 'punishment' from the courts was not likely. Given that the pt in your case assaulted you I think you should press charges. Good luck!