Paul Wells, aged 48, yesterday told gardaí: “I am responsible for killing Kenneth,” when he was charged.
Mr O’Brien, aged 33, a JCB driver from Leland Rd, Clondalkin, Dublin, was reported missing on January 15 after he had left his home, telling family members he was going to work.
The father of one had recently returned from Australia where he had been employed for three years.
The following day, his torso was found in suitcase by walkers at the canal near Cellbridge, Co Kildare.
Investigating gardaí carried out an intensive search operation resulting in other body parts being found in bags in the canal. DNA testing was carried out which concluded the remains where those of Mr O’Brien.
Paul Wells,of Barnamore Park, Finglas, is charged with the murder of Mr O’Brien on or about January 15 and 16. The murder is alleged to have occurred at the defendant’s address.
He sat with his arms folded after he was brought to appear before Judge Anthony Halpin at a late sitting of Dublin District Court yesterday. He had been arrested last Saturday and held for questioning at Naas Garda Station.
Garda Sergeant Gerard Moore told Judge Halpin that at 4.53pm yesterday, he arrested Mr Wells for the purpose of charging.
Mr Wells was charged at 5.16pm at Naas Garda Station. He was handed a true copy of the charge sheet and told that anything he would say would be taken down and used in evidence.
Gda Sgt Moore said that, in reply to the charge, Mr Wells said: “I am responsible for killing Kenneth and I gave a true account of what happened.”
Due to the nature of the offence, the District Court cannot grant bail. Defence solicitor Kieran Conway said he would have to make a bail application in the High Court.
Judge Halpin remanded Mr Wells in custody to appear at Cloverhill District Court on Thursday and granted legal aid.
Mr O’Brien’s partner was present for the brief hearing and watched the proceedings from the public gallery.
A second man arrested in connection with the investigation was released from Garda custody on Thursday without charge and a file is to be sent to the DPP.