On 10 November, Childers was arrested by Free State forces at his home in Glendalough, County Wicklow, while travelling to meet De Valera. He was tried by a military court on the charge of possessing a Spanish-made “Destroyer” .32 calibre semi-automatic pistol on his person in violation of the Emergency Powers Resolution. The pistol had been a gift from Michael Collins while the two men had been on the same side, indeed, were friends, before Collins became head of the pro-treaty Provisional Government. Childers was convicted by the military court and sentenced to death on 20 November. While his appeal against the sentence was still pending, Childers was executed on 24 November by firing squad at the Beggar’s Bush Barracks in Dublin. He was buried at the barracks until 1923 when his body was reinterred in the republican plot of Glasnevin Cemetery.
Before his execution, in a spirit of reconciliation, Childers shook hands with each of the firing squad. He also obtained a promise from his then 16-year-old son, the future President Erskine Hamilton Childers, to seek out and shake the hand of every man who had signed his father’s death warrant. His last words, spoken to them, were (characteristically) in the nature of a joke: “Take a step or two forward, lads. It will be easier that way.”