Although only the murders of Patricia, Jemima, and Helen were officially attributed to the man known as Bible John, similar crimes were theorized to have been committed by the same killer. A 1977 murder, for example, brought Bible John's specter back to the public eye because the victim had spent her last evening at a Glasgow dancehall and was found strangled and without her handbag.
Crow & Samson report that in 1983, a well-to-do Glasgow man hired private investigators to try to track down an old childhood friend whom he thought resembled an artist's depiction of Bible John. The investigators eventually found the man in question living in Holland and, after being questioned, the man was cleared.
A man known as John M. was one of the men who had been a suspect in the original investigations and who had been paraded before Jean for possible identification. His resemblance to the police sketch was remarkable and as the years went on, despite the fact that less and less effort was spent on the three murders as time went on, John M. continued to be considered a prime suspect, and his name continued to come up in the investigation even after he committed suicide in 1980.
By the late 1990s, forensic criminology had progressed to a point not dreamed of in the late 1960s, and Glasgow police wanted to use the bite mark on Helen's body (and, more specifically, the semen left on her clothing) to test for a possible match to John M. After obtaining an inconclusive result on a DNA test using a sample from one of John M.'s siblings, the police began the process to request exhumation of John M.'s body.