dr. dennis sandlin refused to prescribe painkillers to a man who was an addict. left angry and came back with a gun. >> my dad was writing in a chart at the nurse's station and they -- someone heard my dad say you don't want to do this. i take care of a lot of elderly people and he said, well you didn't help me, and that's when he shot him. >> dr. sandlin's murder didn't come as a shock to dr. david green. >> any other phone calls? >> he works at a family practice clinic and addicts come to his clinic to shop for doctors and they use every trick in the book to get him to prescribe every powerful pain medication like oxycontin. it can get ugly. >> have you had people come in and scream at you? >> yeah. >> physically push you or touch you? >> i have less of a problem because i'm male and i'm taller. so -- but one of the things we have to do in our office because i'm the only male doctor is i'm sort of on call for situations like that that involve anybody else, and i'll deal with them. >> reporter: but some doctors do refuse to deal with it. they no longer write pre