didn't do. >> even after questions were raised about isley's involvement in the floyd brown case, mark isley now he's under investigation. we wanted to ask him about this, this six-page confession that he says floyd brown dictated to him verbatim. but isley's not talking. >> over the the years, mark isley climbed the ladder at the sbi. and today he supervises other sbi agents in the medicaid fraud unit. and his case wasn't even investigated internally by the sbi until later this summer after our series ran. >> the news and observer reporters weren't the only ones investigating the sbi. an outside expert, a former fbi agent, would find that floyd brown and greg taylor were just the tip of the iceberg. >> i'm about as hard-lined law enforcement as you can get. law and order, putting bad guys in jail. but what we saw was just not right. ♪ ♪ ♪ look at that car, well, it goes fast ♪ ♪ givin' my dad a heart attack ♪ [ friend ] that is so awesome. ♪ i love my car [ engine revving ] [ male announcer ] that first chevy, yea, it gets under your skin. ♪ it gets under your skin. an accident doesn't have