I actually asked him about it once. The story even further confirms my suspicion.
So he rents out a storage unit and kind of converted it to a garage that he can work on cars in. He had a couple of friends that needed a place to hang for a few days so he let them stay there for a little while. Apparently they were robbing cars and storing the shit there without telling him. Somehow the cops caught onto it and went down there to check it out and they found one of his pay stubs there so they came to pick him up at work because they thought he was doing it and he had to go with them (but eventually proved that he was unaware and had nothing to do with it). So although it's not drug related, he's hanging out with homeless dudes that rob cars. Sounds a little like junkie activities to me...