As the senior Allied officer in four successive Japanese prisoner of war camps, the resistance led by Birchall helped to reduce the Allied death rate from an average of 30% to less than 2%. During his time in the POW camps, he repeatedly stood up to the Japanese and demanded fair treatment of the prisoners, in compliance with the Geneva Convention. In his first camp, he struck a Japanese soldier who was forcing a wounded Australian to work. This earned Birchall a severe beating and solitary confinement, but won him the respect of the other POWs. In 1944, Birchall encountered a situation in which sick men were being forced to work on the docks. He ordered all of the men to stop working until the sick were excused. Birchall was beaten and sent to a special discipline camp, where he again was beaten. He saved many ill soldiers by taking their beatings.