Joseph Quinn is a detective who transferred to the Homicide division after being in narcotics. Quinn takes a liking to Debra Morgan, even giving her a C.I. to help with the Oscar Prado case. Quinn’s past is unknown and even called into question, as Debra is pressured by Internal Affairs agent Yuki Amado to gather evidence against him. Quinn got the Internal Affairs case dropped, and later confessed to Debra that the real source of the Internal Affairs investigation was from the death of a former partner of his and Yuki’s who had a crystal meth addiction. Quinn knew about the partner’s addiction but tried to offer private help instead of informing his superiors.
He’s a FBI special agent recruited by Captain Matthews to identify and arrest the Bay Harbor Butcher.
Vince had been working in the laboratory and in the crime scenes with his partner, Dexter. Among his colleagues, Vince is always known for cracking overtones. He is very much knowledgeable of many sexual subject matters, which makes others look at him as someone who is extremely perverted.
Sgt. James Doakes is a brilliant Special Forces operative in Haiti with an experience of fifteen to twenty years, backing him to be a dependable Homicide detective. He ended up becoming the prime suspect known as the Bay Harbor Butcher, and was later on revealed having an abusive father. He doesn’t like Dexter despite his aura of innocent-seeming, cheerful young person, because Dexter gets into his nerves. The seemingly passion of blood analysis and splats of Dexter unnerves him, especially when Dexter is most of the time had correct analysis on the serial killer’s cases. He couldn’t get to understand why Dexter is always at the right time and place of the murder.