A fifth man has been arrested as part of the investigation into the fatal assault in Rath cemetery earlier this month.
The man who is in his 20s was arrested yesterday evening in Cork.
He was detained under Section 4 Criminal Justice Act, 1984 at Tralee Garda station and was released without charge late last night.
Gardaí say investigations are ongoing.
Mr Dooley was killed while attending a funeral in the Tralee graveyard on October 5th.
Two people have currently been charged in relation to the incident, and a further two men were also arrested and released without charge.
Mr Dooley who was 43 years old and married with seven children had an address in Killarney.