John Malcolm Robb DFC QC was born at Toronto, Ontario (ON), son of Charles Wesley Robb and Nora Margaret (Hamilton) Robb. He was educated at Oakwood Collegiate, University of Toronto and the Osgoode Law School, Toronto ON. Robb practiced law in Toronto, before enlisting in the RCAF in Toronto on March 13th 1941. He received air crew instruction at various training schools in Canada, graduating from No. 6 Service Flying Training School, as a pilot, on February 27th, 1942.

Pilot Officer Robb was posted overseas in March 1942 and after further training was posted to No. 400 Squadron carrying out the role of a reconnaissance and intruder pilot. Robb was with No. 400 Squadron until late 1943 before he was transferred to NO. 414 Squadron. By October 6th 1944, Flight Lieutenant Robb had flown 138 sorties, during which he destroyed at least one enemy aircraft and shared in the destruction of another as well as inflicting much damage on enemy transports.

Robb was awarded the Distinguished Flying Cross (DFC) effective February 6th 1945. Part of his citation reads as follows: This officer has completed a large number of operational sorties including many missions at low level in the face of intense anti-aircraft fire. His aircraft sustained damage on 3 occasions. Despite this Flight Lieutenant Robb has always succeeded in flying back to base. Robb was attached to the Judge Advocate's Branch, RCAF Headquarters, in London England, before being repatriated back to Canada in July 1945.

After WW2, Robb continued the practice of law in Toronto and in 1953 was created Queen's Counsel (QC). In 1954 he was Partner in the Toronto law firm, Slaght, Robb & Hayes. In addition to his law practice, Robb held senior appointments with the federal Minister of Justice. In January 1944 he married Edith Muriel Phillips, daughter of Dr. and Mrs. Walter Phillips. They had one son (John Walter Hamilton Robb) and one daughter (Shelley Jane Robb).