Nick Forster was an assistant district attorney who arranged a perjured statement in order to convict robber and mass murderer Kenny Thompson in 1997.
Eight years later, in 2005, Forster's actions were exposed, which allowed Thompson to get a retrial. Due to the risk of Thompson being acquitted, Forster agreed to testify, during which he admitted to his participation in framing Thompson.
After Thompson was convicted again, Forster resigned from his position. (TBJ: "The Line")