Ray Porter is a lobbyist who appears in The Knight on the Grid. Booth and Sweets identified him as a victim of The Gormogon. At the end of the episode, he was stabbed to death by The Apprentice, who was hiding in the closet in his home. Ever since his death, he was only referred to, by the main characters, as The Lobbyist.
He was cannibalized, and his remains were sent to the Jeffersonian in The Pain in the Heart spread across various multiple containers with bones from Limbo. After revealing the location of Gormogon to Booth and Brennan, Zack Addy confesses to "killing" him and is sent to McKinley Psychiatric Hospital in exchange for full co-operation with Caroline Julian.
In The Perfect Pieces in the Purple Pond he admitted to Sweets that he only gave The Master information on where to find Porter, but he never stabbed him. Sweets wanted him to tell his friends the truth, but Zack was afraid that since he is still an accessory to murder, if his secret were to come out that Booth would throw him in prison and Hodgins assured him that he would not do well in prison. Sweets wanted him to tell the truth because he believes that The Apprentice is still out there, but Zack told him that "The Master" killed him in order to recruit Zack because "there could only ever be two." He reminds Sweets that unless he gives him permission, if he tells anyone the truth, that he would be violating doctor-patient confidentiality. the episode ends with Zack at the sanitarium and Sweets keeping Zack's secret, despite his concerns about him.
In The Hope in the Horror, after a close-to-death encounter with The Puppeteer, Zack admits to Booth and Brennan that he didn't kill Porter. Brennan agreed to re-examine the evidence and Booth agreed to help him get released from the institution.
Porter's remains and murder scene are re-examined by Jack Hodgins in The Flaw in the Saw, and he comes across evidence on his rib that could potentially exonerate Zack. The bacterial signature of The Apprentice preserved by Anthrax. After presenting the new evidence to Cam, she refuses to believe that it is true and accuses Hodgins of planting evidence. Despite the fact that she refuses to accept the evidence, she goes over Hodgins' findings as he furiously leaves. Despite going over the evidence, Cam and Brennan ultimately throw it out as was later revealed.
In The Steal in the Wheels, after all attempts to find evidence at the murder scene pointing to Zack's innocence fail, Hodgins searches for the body of the Apprentice, Porter's real killer to prove he killed Porter and not Zack. With the help of Doctor Gordon Wyatt, Hodgins locates the Apprentice's body and he is discovered to have what is presumably Porter's blood on his cuff, the evidence needed to exonerate Zack.
In The Day in the Life, Zack has his appeal where Hodgins testifies that the blood found on the Apprentice's body was an exact match to that of Ray Porter, proving that the Apprentice was the killer. Hodgins also established a protocol where no one examined the evidence alone to any prevent accusations of evidence tampering. Ultimately, in light of this new evidence, Zack's conviction in the murder of Ray Porter is reversed and his life sentence overturned. While Zack is exonerated for Porter's murder, he is not however cleared of the charge of aiding a known killer. As a result, Zack will still need to serve the last thirteen months on that charge before he is finally released back into society.