Chisholm's father was a lay preacher in Dundee City Prison when John was growing up, giving him an interest in criminology.
[4] Chisholm was found dead in his automobile in High Park having killed himself by a single shotgun wound to the head.
[5] He had been suffering from ill health since the previous Christmas - Police Commission Chairman C. O. Bick told the Daily Star that his "nerves" were bad, and had been rumoured for several weeks to be considering submitting his resignation.
Chisholm had often clashed with Bick, the first chairman of the new Metropolitan Toronto Police Commission, particularly over questions of authority.
Chisolm was unable to cope with the strain of managing the merging of thirteen separate police departments and this is thought to have led to his suicide.