jut comes ok stated in many cases by a man named mark gerragos.s down with the lawyer to the stars. >> reporter: he's a celebrity lawyer, not just because his client roster includes so many famous names. chris brown, for instance. still on probation for beating his girlfriend rhianna. mark gerragos is a celebrity lawyer in the sense that he's one of the best known trial lawyers in the country. >> i don't believe he's responsible. >> reporter: famous for defending the infamous, including scott peterson. >> do you really believe scott peterson is innocent? really? >> look, i will tell you i'm not even sure that there was a murder committed. >> reporter: gerragos famously lost that case. his client now on death row for killing his wife laci peterson. it cost him his most famous client, michael jackson. do you regret choosing scott peterson over michael jackson? >> it was a death penalty case. i did not want to drop client. >> he said you've got to choose here. >> i told him look, i'm not going to dump one client for another. if you're not comfortable