Finn Colclough has been found not guilty of murder, but guilty of the manslaughter of Sean Nolan in Dublin last year.
The 18-year-old from Waterloo Road in Dublin 4 had denied murdering 18-year-old Sean Nolan from Fairview.
Colclough, who was 17 at the time of this incident, told gardaí he had felt threatened by Sean Nolan and his friends when they gathered outside his home at 4am in May 2007.
They had met earlier on the street and had asked Colclough and his friends for directions. The victim's friends said they later stopped only to ask for a corkscrew to open a bottle of wine.
But Finn Colclough told gardaí that he was frightened by them. He ran from his house with two knives screaming at them to go away.
When Sean Nolan confronted him they struggled and Mr Nolan was stabbed in the chest. Colclough told gardaí it was an accident.
The prosecution said he had no reason to feel threatened and had come from the safety of his house and ran 16m to the public footpath where the victim was.
Sean Nolan and his friends had been celebrating their graduation from secondary school on the night he died.
After the jury delivered its unanimous verdict, Mr Justice Paul Carney thanked it for its care and consideration in what was a difficult case.
Finn Conclough will be sentenced in December.
