Between 1914 and their disbandment the Royal Dublin Fusiliers had 22 men sentenced to death for a variety of crimes - of these 3 were actually executed. Because regiments were not proud of courts martial, evidence is somewhat scanty.
At the end of 2004, a report commissioned by the Irish government into the execution of Irish soldiers was completed. In it was revealed the fundamental injustice of British 'field general courts martial' during the First World War. These were military courts in the proximity of the front line, speedily dispensing exemplary 'justice' including death sentences. The report contains a close examination of the cases of 26 Irish soldiers executed by firing squad. They had access to all but one of the files (why they were not able to access that I do not know), and their conclusion was that all the cases could have been successfully appealed had a normal set of legal standards been applied, including the need for sufficient proof and the proper consideration of medical evidence. The courts martial files were released in 1990.
If you were Irish – whether Protestant or Catholic, Ulsterman or Dubliner, whether fighting out of loyalty to the Union or for the promise of Home Rule – on first impressions you were five times more likely to be shot by firing squad. In the rest of the British army 277 out of 7,031,078 men (7,165,280 - 134,202 recruited in Ireland) or one in every 25,000 troops was sentenced to execution by firing squad. Among the Irish soldiers the figure is 26 in 134,202 men recruited from Ireland (plus whatever the figure is for Irishmen recruited in England) or 1 in 5000. (The 1 in 5000 figure should be augmented by Irish recruits in England)
Courts martial of all sort from Aug 1914 to Sept 1915 in the 2nd Royal Dublin Fusiliers amounted to 150 cases. This fell to 95 cases in the period Oct 1915 to Sep 1916 for the 2nd Royal Dublin Fusiliers (Average in this period for a regular Irish Battalion was 58)
The results of Courts Martial in the Royal Dublin Fusiliers are discussed under separate headings
Executed - 3 men were shot, 2 for desertion and 1 for murder
POWs who forfeited medals perhaps under suspicion of joining Casements Irish Brigade
Deserted - a great many have "deserter" on their medal card
Forfeited medals - those whose medal card shave "forfeited medals" but "desertion" is not explicitly stated
Courts Martial various
Royal Dublin Fusiliers
Royal Dublin Fusiliers