In 1915, he was offered a promotion and a transfer to Haulbowline Island, but declined on the grounds that this entailed enlisting in the Royal Navy, albeit in a purely administrative role.

[4] In 1918, he was sentenced to five years penal servitude for possession of arms and plans of the British military fortifications at Bere Island.

[7] According to Barry, Hurley led an ambush of the Royal Irish Constabulary at Ahawadda, in April 1920 killing three policemen, wounding one and taking their arms and ammunition.

In July of that year, Hurley led a successful attack on Coastguard station at Howes Strand, capturing a large amount of weapons and ammunition.

"[8]: 16–17 Hurley was present at the Tooreen ambush in October 1920 and subsequently was part of an assassination attempt on a judge who gave 'harsh sentences' to IRA members.

He also toured IRA units to assess the impact of the Catholic Bishop of Cork, Dr. Colohan's decree of excommunication on the guerrilla movement.