|Affiliation||Ku Klux Klan|
|Pathology|| White supremacist|
|Family|| Unnamed son (deceased)|
Unnamed daughter-in-law (deceased)
Catherine Harrison (granddaughter)
Grant Harrison is a white supremacist who in 1964 brutally raped Lorna Talcott while in full view of her son Dwight. Years later, he manipulated his granddaughter Catherine into committing perjury.
In 1964, while Lorna Talcott and her son Dwight were going door to door for a registration drive, a van pulled up beside them and three members of the Ku Klux Klan (one of whom was Grant) pull her and her son into the car and viciously beat and gang rape Lorna while making her son watch by holding a gun to his head. When Grant and his friends were questioned they claimed to the police that Lorna was a prostitute. With no sufficient evidence, neither Grant nor his fellow supremacists were charged. Grant later attempted to raise his son's daughter Catherine to be a racist, but she refused.
When Catherine was taken to the hospital for being "assaulted", Grant comes to the hospital to console her. Grant tells Catherine that she should move in with him, she at first refuses but Detective Stabler tells her that it would be best for her to not be in the apartment during the investigation. While with him Catherine tells him that she was't really raped but Grant tells her that if she says that nobody would believe her and that she needs to says she was raped by a black man. While moving out Catherine is arguing with her best friend Isabelle because she told the detectives that the one who raped her was Isabelle's brother Kevin Wright during which Grant tells Isabelle that Catherine does not belong there.
When the detectives tell Catherine that it was not Kevin who broke into her room they ask her about the attack again which gets Grant angry. Catherine then tells the detectives about Dwight who brings fresh vegetables to the school she teaches at. While his daughter is testifying about how Dwight "assaulted" her Grant walks in and sees Dwight's mother, recognizing her from when he and his friends raped her. During Jonah Dekker's cross examination of Catherine Grant gets up and loudly accuses Jonah of re-traumatizing Catherine and while he is being removed from the court he accuses Dwight of being a pervert and says that his mother is a slut and a whore. The SVU detectives then learn about how Grant and his friends attacked Dwight's mother. Later while Detective Fin Tutuola is attempting to stop Jonah from confronting Grant for raping his aunt Grant tells them to leave, adding racist comments.
When it is revealed that Dwight planned to rape Catherine for what Grant did to his mother but could't bring himself to do such a thing Catherine is arrested for perjury. When Grant sees Catherine in cuffs he asked what happened and Stabler told him that Catherine is being arrested for perjury because of her grandfather's deceitful advice. When Grant offers to help her, she denies it and berates her grandfather for making her who she was.