[4] His nickname, Jigsaw John, originated in his early career with a dismemberment murder he solved in Griffith Park in which the victim had been cut up jigsaw-style.

The moniker caught on because of his ability to piece clues together in difficult cases, resulting in many arrests and convictions.

[6] St. John was renowned within the Robbery-Homicide Division (RHD) for his amazing memory and dogged determination in working the minutiae that led to solving murders and getting convictions.

However, as criminal science became more sophisticated, he kept up with the times, taking advantage of modern scientific crime analysis, forensic techniques, and the benefits of a new computerized age.

[12] In 1982, St. John became the second recipient of the LAPD's Distinguished Service Medal for his eight-year investigation resulting in the conviction of William Bonin.