Continuing our theme of Prison photo's I have found this one from the Leeds University Liddle collection.
Compulsory military service (conscription) for all men aged 18-50 in Britain was introduced in 1916 with the Military Service Act for WW1. Those who refused to go into military service were often imprisoned or sent to work camps, and there was one of these at Dyce, near Aberdeen.
In those day being a Conscientious objector was not the easy option. Many died in those prison work camps.