The prosecution believes David Mahon’s interviews with Gardai were “littered with lies and clearly point to his guilt”.

The 45-year-old is accused of murdering his stepson Dean Fitzpatrick outside his apartment at Northern Cross in Dublin in May 2013.

Dave Mahon claims Dean called over to his apartment on May 25th 2013 and pulled a knife on him during a row over a stolen water bottle.

He told Gardai he took it off him but had it in his hand during a later confrontation that ended with his stepson being fatally stabbed.

He said it was accident and also spoke about Dean’s history of self-harm and mentioned the possibility he wanted to walk onto the blade.

During his closing speech this morning, Remy Farrell, SC for the DPP, accused Mr. Mahon of telling lie after lie following his arrest. He described them as crucial lies. Lies used to assist him only and lies that clearly point to his guilt, he said.

He also spoke about the post mortem, and while he accepted it wasn’t able to assist either side’s version of events, he said it was clearly a wound that required a person to have a tensed hand while holding a knife.

Mr. Mahon’s barrister will address the jurors for a final time next week before they begin their deliberations.