Dubliner David Mahon has been found guilty of the manslaughter of his stepson, Dean Fitzpatrick.
Mahon, 45, had denied murdering Mr Fitzpatrick on 26 May 2013. He claimed Mr Fitzpatrick (below) walked into the knife he was holding and that his death was an accident.
Earlier, the jury of six men and six women told Ms Justice Margaret Heneghan that they could not reach a unanimous verdict.
The judge told them the circumstances had now arisen in which they could reach a verdict on which at least ten of them were agreed.
Mahon was found guilty of manslaughter by a 10-2 majority verdict at the Central Criminal Court this afternoon.
He has been remanded in custody and will be sentenced on 30 May.
The court heard evidence from the deputy state pathologist, Dr Michael Curtis, who said Mr Fitzpatrick bled to death as a result of a single stab wound to the abdomen.
The 23-year-old received the injury outside the apartment that his mother, Audrey Fitzpatrick, shared with Mahon at Burnell Square, Northern Cross, Dublin.
The State argued that the 45-year-old accused was drunk, angry and agitated when he thrust a knife into his stepson with deadly intent. Mr Mahon claimed his death was an accident or possible suicide.
He said that his stepson had pulled a knife on him and that he had wrestled it from him and put it into his pocket. He said he then took the knife out to show it to him and that Mr Fitzpatrick had walked onto it.
Dr Curtis said the wound was inflicted with moderate or considerable force.
But he said his examination could not tell if the wound had been inflicted with a deliberate thrust of the knife or if Mr Fitzpatrick had "run on" to a knife being held by someone else.
Dr Curtis said the nature of the wound meant that either scenario was possible.
The jury began deliberating at lunchtime on Wednesday.
They asked the judge a number of questions. They asked to see CCTV footage, they also asked for the knife block and another knife from the apartment.
They also asked for legal definitions of a number of different terms including manslaughter, recklessness and intention to frighten.
The judge told them that if they believed Mr Fitzpatrick's death was an accident they had to acquit Mahon.
If they believed that Mr Fitzpatrick was unlawfully killed by Mahon but that he did not intend to kill or cause serious injury to Mr Fitzpatrick then they should convict him of manslaughter.
The jury took eight hours and 16 minutes to reach their verdict.
Dean Fitzpatrick is the older brother of missing teenager Amy Fitzpatrick.
