A man sitting in a hot tub at a hotel in Mission Valley, Calif., got into a casual conversation with a woman and two men who happened to be in there with them. They said they were staying at the hotel because their crack lab blew up. So he said he was a drug dealer too. They were joking. He was not. To make matters worse, his new acquaintances were sheriff’s deputies who were in town for a narcotics training course. He was arrested.