Ronan Byrne (31) is alleged to have fractured the deceased's leg with a bat during an altercation. A jury has heard that days after the man's leg was put in a cast at a hospital, a blood clot developed in his leg which travelled to his heart and this clot proved fatal.
Byrne of Lohunda Downs, Clonsilla, Blanchardstown, Dublin, has pleaded not guilty at Dublin Circuit Criminal Court to the unlawful killing of James Marren (57) at that address on October 31, 2013.
He also denies production of a baseball bat during a dispute and assault of James Marren causing him harm at the same address five days earlier on October 26, 2013.
The court heard the defendant's mother Mairead Byrne and Mr Marren had been in a relationship for at least 13 years.
On the second day of the trial today, Ms Byrne told Philipp Rahn BL, prosecuting, that on October 26, 2013, she and Mr Marren returned home in the evening having been out with her brother and his wife.
Ms Byrne said she went to bed because she was supposed to get up early the next morning. She said the next thing she remembered was hearing shouting Mr Marren shouting at her son the accused man downstairs.
She said she came downstairs and told them to stop before returning upstairs. She said she heard screaming and shouting from downstairs, but she did not recall anything else prior to the ambulance arriving.
Ms Byrne said after the ambulance left there was lots of blood on the floor, which she cleaned. She said Mr Marren returned to the house from hospital the following day.
She said over the following days she asked Mr Marren would he go back to hospital, but he said he would not go back. She said she was not present in the house when an ambulance was called for him on October 31, as she was in a shop buying him Panadol because he said he had a headache.
Ms Byrne agreed with Padraig Dwyer SC, defending, that Mr Marren would shout a lot at the accused man, but not her other sons. She said she recalled Mr Marren assaulting and hurting her son, the accused.
She agreed with counsel that on the evening of the incident, Mr Marren had had a good few drinks. She said it was fair to say Mr Marren was verbally abusing her son, but she did not see the fight between them.
Ms Byrne said she thought the abuse started a few years after Mr Marren arrived at the house. She said she remembered the police being called and she said he had hit her child.
She agreed that Mr Marren discharged himself from hospital the day after the incident. She said a couple of times he said he was not feeling well and she wanted to ring an ambulance, but he would not let her.
Ms Byrne agreed that on the day of his death, Mr Marren complained about the plaster on his leg. She said he said it was too tight and his leg was sore.
She agreed it was fair to say that Mr Marren would assault her son the accused, not the other way around. She agreed this would have been the first time her son retaliated.
Hugh Kenny told Mr Rahn that he was a neighbour of the accused and the deceased and that on October 26, 2013, he heard a commotion from their house. He said it escalated to the point where there was screaming and shouting and crying.
Mr Kenny said he had CCTV hooked up to his television and saw two “young lads” outside. He said he went out to them, asked if they knew first aid and asked if they wanted him to go into the house.
He said when he went inside, Mr Marren was lying on the bathroom floor and was already in the recovery position. He said there was a large wound on his forehead and he got towels to stem the bleeding.
Mr Kenny said Mr Marren regained consciousness, he tried to sit up and was looking to leave the house at a certain point. He said that because the bleeding had stopped and an ambulance was on the way, he felt he could not do anything more and left the house.
Mr Kenny agreed with Mr Dwyer that it was a person who was holding a child in his arms who told him he should go into the house and give first aid.
He agreed with counsel that after leaving the house, he told a “young lad” who was on the phone outside that Mr Marren was “grand”.
He said he said this because Mr Marren had regained consciousness, he was not bleeding and he did not think he was in immediate danger.
The trial continues before Judge Patricia Ryan and a jury.