He joined the 9th Battalion, CEF, and variously worked at the 1st Canadian Motor Machine Gun Brigade and at Corps Headquarters.

He completed staff college in Quetta in 1923–1924, and was posted to the War Office in London, England, in 1930.

Lawson was placed in charge of the west brigade,[2] which included the Winnipeg Grenadiers, the Royal Scots, the Punjab Regiment (India) and the Canadian Signallers.

The Japanese landed on Hong Kong Island on 18 December 1941 with the intent to split the defenders in two.

Lawson radioed his commanders that he was "going outside to fight his way out" and left his splinter proof shelter with a small group of his officers.

[2][3][4] When the Japanese arrived and found his body, they gave him a military burial nearby in Wong Nai Chong Gap out of respect for his courage.