A Dublin man must wait to hear the outcome of his appeal against a seven-year sentence for killing his partner's son.
David Mahon (46) had pleaded not guilty to the murder of Dean Fitzpatrick (23), the older brother of missing teenager Amy, on May 26, 2013.
Mr Fitzpatrick received a stab wound to the abdomen outside the flat his mother, Audrey Fitzpatrick, shared with Mahon at Burnell Square, Northern Cross, on the Malahide Road.
The two-week trial heard Mahon had been in a relationship with Ms Fitzpatrick for 12 years.
The State argued that Mahon was drunk, angry and agitated when he thrust a knife into his stepson with deadly intent.
Mahon claimed his death was an accident or possible suicide and that Mr Fitzpatrick had "walked into the knife" while they had been arguing.
A Central Criminal Court jury found Mahon not guilty of murder but guilty of manslaughter and he was sentenced to seven years in jail by Ms Justice Margaret Heneghan in June 2016.
Opening an appeal against the severity of his sentence yesterday, Mahon's barrister, Sean Guerin, said there was no case "quite like this".
He said Mahon was factually proven only to have produced the knife. He produced the knife, he didn't thrust it, he didn't stab, and because he didn't thrust it, he didn't commit an act that could have amounted to a physical assault.
Mr Guerin added there were two distinct views open to the jury. The prosecution case for murder was that Mahon took out a knife and deliberately stabbed Mr Fitzpatrick, causing his death.
The alternative view was that Mahon had merely produced the knife. He either intended to put him in fear or was reckless to put him in fear.
Mr Guerin said the only conclusion which could be drawn from the verdict is that the jury were not satisfied beyond a reasonable doubt that Mahon had stabbed the deceased.
Counsel for the Director of Public Prosecutions, Anne-Marie Lawlor, said the entire submission from Mahon's lawyers was "predicated on a fallacy".
Ms Lawlor said the word manslaughter was not used once by the defence in their closing speech to the jury and it was never suggested this was an involuntary manslaughter and that was an available verdict.
Mr Justice Michael Peart, who sat with Mr Justice George Birmingham and Mr Justice Alan Mahon, said the court would reserve judgment.