So you see, Inspector, DNA's not going to cut it in court, is it? It was a very good try, though. But no cigar, as they say.
Cartwright taunting Neville Parker
David Cartwright appears in 12:6 A Murder Forewarned.
Biography[]
From a young age, David Cartwright was fascinated with criminals and why they choose to do bad things. By the time of Death in Paradise, he's a well-respected and renowned criminologist who has authored several books on criminal psychology.
He advised the police on active criminal cases, including one particular serial killer case. Even after the case was solved, Cartwright became obsessed with why the killer had done what he did. He devoted most of his time to interviewing the man in prison, desperately trying to empathise with the killer and understand his actions. This eventually cost Cartwright his sanity, and his colleagues at the university where he worked forced him to step down. Cartwright was outraged that his career was over and became bitter and vengeful, but there was nothing he could do other than retire to the Caribbean island of Saint Marie.
Unknown to everyone else, Cartwright was even more dangerous than he appeared. Thanks to his warped mind, Cartwright now fantasised about murdering random people just to see what it would feel like. Two years after moving to Saint Marie, Cartwright finally decided to act on his new murderous desires. His chosen victim was water taxi driver Jake Dalton, the husband of Cartwright's cleaner Rose Dalton. He knew that Rose was cheating on Jake with another man, and it's heavily implied that he intends to frame Rose for her husband's murder.
A few weeks before committing the crime, Cartwright arranged an online Q&A session to take place at the same time as he plans to kill Jake. He also changed the locks on his door, giving him an excuse to visit Rose's house and thus a plausible reason why his DNA might be found there. Through conversations with Rose, Cartwright learned Jake's schedule and how it aligns with his wife's. He thus knew that Jake would be at home by himself when Rose was cleaning his room. When Rose arrived at his house in the morning, Cartwright told her that he would be in his study the whole time for his Q&A so she wouldn't disturb him. With Rose thinking he was in his study, he slipped out and went round to her house, where he stabbed Jake to death. Cartwright then arranged the wall behind him to look exactly like the wall in his study at home. With his victim's body not even cold, Cartwright proceeded to host his Q&A session from the crime scene, with the redecorated wall making it seem as though he was at home when the murder was committed. Just for fun, Cartwright had previously sent Detective Inspector Neville Parker of the Saint Marie Police a letter informing him that a murder would be committed that day. -Credit from Villians Wiki.