Pierce is a police officer at the SBPD. The first time Shawn sees Pierce, he notices that he only pretend-signed for a package he requested from the evidence room. When Internal Affairs officer Dan Cooper turns out to have been murdered only a very short time before, Shawn suggests to Juliet that due to Pierce's suspicious behavior earlier it could very well have been him who Cooper had been investigating at the time of his death, thereby giving Pierce plenty of reason to kill him. Juliet follows up on Shawn's lead and finds out that Pierce had been smuggling drugs out of the evidence room on the regular. She and Lassiter arrest him, but they later discover that he is not in fact a murderer as well when they find the killer's car at the Box Canyon Commune while Pierce is in custody.