Watters had denied the allegation, saying Mr Cahill and his friend Ashley Keogh had tried to push their way in his front door and there was a scuffle.
Finding Watters guilty of assault, Judge Dermot Dempsey sentenced him to two months in prison but suspended it for one year. Watters had denied assaulting his next-door neighbour Brendan Cahill at Beverton Meadows in Donabate on March 12 last.
Mr Cahill said he was down at his father's farm when he rang his wife around 7pm. She was upset about the parking so when he came home he decided to call around to his next-door neighbour to speak to him.
Mr Cahill claimed there are six communal parking spaces for four houses but Watters had four vehicles parked in the area.
He said he knocked on the defendant's door and stood back a little. Mr Cahill claimed Watters "charged up the hallway" and immediately hit him a smack, with a closed fist, on the side of his head.
He said his friend, Mr Keogh, stepped out from his doorway, and said to Watters, "hey, what are you doing, that's assault".
Mr Cahill claimed Watters then threatened to kill them if they complained to the gardai.
Watters claimed his three children were in hysterics, and since this incident he's been forced to install CCTV cameras.
Judge Dempsey said the victim's evidence was quite clear and he convicted Watters of assault.