Change all the locks.
Notify the police that he has asssulted your father, and that you witnessed the assult.
Emphasize to the police that you fear further assults.
When he returns, and goes bolistic over the new locks, call 911. Say you fear for your safety, and that he is trying to break in.
He should be arrested, and a condition of his release is that he not try to return.
That is how it would work in Canada.
Good luck.
PS. Anyone that claims a "right" to be a freeloader deserves the worst that they can get, in my book.