Shortly after retiring as a judge he took on the task of chairing a Royal Commission known as the Hughes Inquiry into allegations of child abuse by members of the Christian Brothers of Ireland at Mount Cashel Orphanage in Newfoundland.
[1] With the arrival of the Second World War joined the Officers' Training Corps and was commissioned as a lieutenant into The Queen's Own Rifles of Canada.
He went out by ship, travelling with the war artist Charles Comfort, who later said he had found Hughes "a spirited companion, with a refreshing sense of humour and a staggering knowledge of history.
[1] After a few weeks, W. E. C. Harrison, professor of history at Queen's University and Hughes's immediate superior in the 1st CFHS, arrived to visit him, in cold weather, under heavy fire from German artillery.
He reported back "Sam Hughes remained outwardly unperturbed by the discomforts of the situation," he wrote, "although I have never seen anyone disappear more quickly than on the three occasions when Jerry's planes came over.
"[2] After a year on active service, at the end of 1944, Stacey brought Hughes back to England to work with him to begin to collate the records the field historians had collected.
[1] Hughes later wrote in his autobiography, Steering the Course, that this was in accordance with a plan of Stacey's and would prevent him from leaving England again for the duration of the war and some time after it.
[4] In April 1946, although Stacey had hoped to keep him longer, Hughes returned to Osgood Hall to complete his training for the law,[1] retiring from the Canadian Army as a Lieutenant-Colonel.