Nothing he does has anything to do with you! I am so sorry things have turned out this way! I am very impressed with you for involving the police! I tried everything to keep my ABF safe from run-ins with the law and shouldn't have. It looks like you are much better at looking after yourself than I was.
I worry that you run a very real risk of becoming entangled with the drug scene by letting him stay with you. My BF is an alcoholic, but when I was gone for a few weeks one time, he let other people stay at my place and I found a little plastic baggie and a rolled up piece of paper on my desk. I was livid and told him that he will never invite people into our home who take drugs. I was so scared of being in any shape or form affiliated with illegal that I literally had a panic attack over this.
Of course it's your decision, but I think this situation goes beyond enabling a drug addict. He puts you in danger just by being affiliated with you...