Baggallay, an army prosecutor who had been a member of courts that sentenced Volunteers to death under the Restoration of Order in Ireland Regulations[6] on Bloody Sunday (1920).

The defence complained that it was unfair to suggest the witnesses "were prepared to come up and perjure themselves on behalf of the prisoner" because "they belonged to a certain class and might hold certain political opinions".

[7] The military court did, however, trust the evidence of an army officer who lived in the same house as Baggallay and who had identified Whelan as the man covering him with a revolver during the raid.

[citation needed] Following the Two for One policy that decreed the assassination of two members of the Royal Irish Constabulary (RIC) in retaliation for every executed Irish Volunteer, the IRA in Whelan's native Clifden ambushed and fatally shot RIC Constables Charles Reynolds and Thomas Sweeney at Eddie King's Corner in on 16 March 1921.

[10] In response to the RIC's request for assistance over the wireless, a trainload of Black and Tans arrived in Clifden from Galway City in the early hours of St Patrick's Day, 17 March 1921, and proceeded to "burn, plunder and murder".

[12] He was one of a group of men hanged in Mountjoy Prison in the period 1920-1921 who are commonly referred to as The Forgotten Ten.