Welcome trex2strike, If you don't like Josh, why hang out with him? Friends are people who you like.
Before contacting the police, do an internet search for Josh. If Josh has broken the law, there should be a warrant for his arrest, possibly on the internet. If Josh is a felon and you are afraid of being labeled a snitch, I would use an anonymous police tip line to inform the police where/how to find Josh. Don't contact the police to get Josh out of your life. Do it because Josh is a felon.
Peace be with you and everyone, who you love,
Robert