Liam Luke Schoupp was two months shy of his 13th birthday when he and two mates persuaded Alphonse Verryt, the father of another friend, to allow them to "skitch" a ride up Hillcrest Avenue on January 30, 2007.

The term "skitching" refers to the act of being pulled along by a vehicle while riding on a skateboard, skates, bicycle etc.

Mr Schoupp, a relatively inexperienced rider who had only had his skateboard since Christmas, lost his balance a few hundred metres up the road and fell, hitting his head on the bitumen. The car was travelling at less than 20km/h, however, he was not wearing a helmet at the time.

Mr Schoupp suffered a hairline fracture to the back, lower part of his skull and significant bruising to the frontal lobes of his brain.

He was in hospital for a week. He has experienced ongoing problems since the accident, including fatigue, learning difficulties, loss of memory, difficulty with organisation and planning and had developed obsessive compulsive disorder in some parts of his life.

Mr Schoupp's family subsequently launched legal action against Mr Verryt, claiming he had been negligent in allowing their son to hitch a ride behind the car.

In a District Court hearing in 2014, Mr Verryt's insurer, CTP, conceded its client was in breach of the duty of care he owed Mr Schoupp, however, claimed the boy had been partly to blame because he'd actively agreed to the skitching, knowing it was "inherently dangerous" and had failed to wear a helmet.

In his judgment, Justice Leonard Levy said while the boy had been negligent in his actions, the blame lay at the feet of Mr Verryt.

"It was Mr Verryt who, as a mature adult, and himself a parent of a teenage son, had the ultimate say on whether or not to move his vehicle forward knowing that at the time, Mr Schoupp and the other boys would be holding on to the back of his vehicle," he said.

"If Mr Verryt had acted with reasonable and prudent care at that moment, by simply refusing to drive in those circumstances, the accident would not have occurred as it did."

He awarded Mr Schoupp $2.2 million in damages, including $610,000 in future economic loss, $712,000 for future professional help with domestic chores and $250,000 to pay a "case manager" for guidance in making decisions.

However, lawyers for Mr Verryt appealed the decision to the NSW Court of Appeal, claiming Justice Levy was wrong in attributing 100 per cent of the blame to their client. They also disputed several of the individual sums awarded to the now 21-year-old.

The Court of Appeal agreed to reduce some of the individual damage amounts, bringing the total down to $1.86 million. The presiding judges then reduced that figure by a further 10 per cent, to account for what they found had been the degree of Mr Schoupp's own irresponsibility in what had occurred. The court reached a final payout figure of $1.67 million.