 In the series finale, Shawn is about to confess on a video farewell to not being psychic but Lassiter destroys the disc first, showing that while he always knew the truth about Shawn, he has come to accept Spencer as a friend; it may also have been a way to "keep the mystery alive" in a way that Shawn would approve.He generally distrusts Shawn and does not believe that he is psychic as he claims to be, but has come to have a grudging respect for his investigation skills, something he admits in one episode while drunk.Omundson describes his character's animosity towards Shawn as stemming from the fact that Lassiter has worked hard to climb the chain of command and become good at his job.