All meals should be delivered to the cell, and if the bad boy does not slide the dirty dish out, no more food deliveries till he does. The cell door is not opened during his lifetime, nor after till his body bloats up and stinks.
Never allow him to be close enough to harm another human being. While working a cell block containing the "onion field" killers, Smith and Powell in 1969 while they were appealing their death sentence, their attorney tried to smuggle a gun into them. I'd have been their first target.