The Riverside Police Department (RPD) is the agency responsible for the unsolved Murder of Cheri Jo Bates. The department received one of the type-written Cheri Jo Bates confession letters in November 1966 and a handwritten letter in 1967 (see Cheri Jo Bates 1967 letters).
The RPD has strongly rejected the theory that Bates was a victim of the Zodiac Killer. According to the article, detective Jim Simons stated that one individual remained of interest, but mitochondrial DNA testing did not link that person to the crime. A 2016 Press-Enterprise report indicated the RPD believes it knows the killer’s identity but lacked sufficient evidence to make an arrest.