A man on trial for murdering his stepson told detectives he was not acting in self-defence, the Central Criminal Court has heard.
David Mahon has pleaded not guilty to murdering Dean Fitzpatrick outside his apartment in Clarehall in Dublin in May 2013.
During Garda interviews, which are being read to the court today, Mr Mahon was asked if he believed he had used excessive force with the knife to which he replied "obviously I do, he's dead".
Mr Mahon said "I was not defending myself. I had taken it [the knife] out to say why did you pull this on your auld fella".
He said "did I mean to kill him ... not in a million years ... but he's still dead".
The court has previously heard evidence that 23-year-old Mr Fitzpatrick called to Mr Mahon's apartment and pulled a knife on his stepfather.
Mr Mahon told detectives he took the knife off him and a short time later was holding it in front of himself when Dean walked into it.
The Central Criminal Court has heard that during garda interviews Mr Mahon said he had started to doubt himself over what happened.
During the interviews Mr Mahon told detectives that while sitting in a cell he had started to doubt himself about whether Mr Fitzpatrick walked into the knife or if he had pushed him.
He later said he was sure Mr Fitzpatrick had walked into the knife.
The court heard that Mr Fitzpatrick had a death wish over feelings of guilt about his missing sister, Amy.
Sgt Eddie Carroll said detectives looked at a file on Dean Fitzpatrick held by the north Dublin Mental Health Services.
Sgt Carroll said Mr Fitzpatrick had a history of substance abuse since he was 11-years-old.
Mr Fitzpatrick told medical personnel that when he drank he felt like Superman, nothing could happen to him.
He said he had three or four mood swings a day and he could not control it and needed to take something to calm him down.
Mr Fitzpatrick was referred to psychiatric services in 2009 for low mood and self harming.
Earlier the court heard Mr Mahon told gardaí he wished it was him who was dead and not in a million years did he intend to harm his stepson.
The 23-year-old was stabbed outside Mr Mahon's apartment on Burnell Square, northern Cross in Dublin.
Mr Mahon, who is the partner of Mr Fitzpatrick's mother Audrey, said he thought he had only nicked his stepson with a knife.
During garda interviews Mr Mahon said if he had realised how serious it was he would have called an ambulance.
He told Detective Garda Brendan Mears that Mr Fitzpatrick walked into the knife, said "Ah" and went down the stairs.
Mr Mahon said there was only a little bit of blood on the knife so he thought he had only nicked Mr Fitzpatrick.
He said "I have nothing to hide ... it's my fault ... he was 23 years old ... what will Audrey say?"
He said Mr Fitzpatrick had been self-harming and seemed to enjoy it.
Mr Mahon said he and Ms Fitzpatrick had been together for 12 years and had moved to Spain with her two children, Mr Fitzpatrick and his sister Amy, and it was all happy family.
He told the detectives that Amy went missing over there.
He said himself and Ms Fitzpatrick were millionaires with eight or nine houses but spent all their money looking for Amy.
He said Amy was an angel but Mr Fitzpatrick was not and pulled knives on him a number of times and a gun around seven months before he died.
Earlier, a number of admissions were made on behalf of Mr Mahon by his barrister.
These included that he was lawfully arrested on 26 May 2013 and lawfully detained in Coolock Garda Station.
He also made admissions that CCTV was lawfully obtained as was phone chronology and that the body of the deceased was lawfully observed.
