David Mahon says Dean Fitzpatrick grabbed a knife and started waving at him
The jurors have now heard all the prosecution’s evidence in the trial of David Mahon, who’s accused of murdering his stepson in Dublin.
The jury has heard that Mahon told gardaí he "panicked" and did not realise the seriousness of what happened during a fight with his stepson.
The 45-year-old, who denies murdering Dean Fitzpatrick, claims he ran into a knife he had taken off him at his apartment at Northern Cross in north Dublin.
Dean, a 23-year-old father of one, called over to Mr Mahon's apartment on the night of May 25th 2013.
The court heard they argued and Mr Mahon told gardaí that Dean grabbed a knife from the kitchen and started waving at him.
He said he took it from him, and later confronted him with it on the landing outside his apartment.
He said he showed it to him and asked why he would pull a knife on his father.
He claims Dean then just came at him and while he saw some blood on the knife afterwards, he did not think it was serious.
He said he would have called an ambulance if he did.
Instead he "panicked" and left the apartment with a friend. He said he threw the knife out a car window as they drove around north Dublin.
He told gardaí that Dean would self-harm while they were in Spain and seemed to enjoy it, and he thought maybe he wanted to run on the knife.
The trial continues.