Bundaberg man Alister Spong hugged his wife in a long embrace after a jury cleared him over the death of his friend at Canberra's Summernats Car festival last year.

Mr Spong, 33, was charged with culpable driving causing death in the ACT Supreme Court.

His friend Luke Newsome was travelling on the back of a 1942 utility truck with several others when he fell off, suffering fatal head injuries.

Mr Newsome died in hospital the next day.

Mr Spong had told the court he was attempting what is known as a "chirpee," or a short wheel spin, while driving in first gear on the cruise track at Summernats.

Instead of spinning, the wheels bit the bitumen and the truck lurched forward, throwing Mr Newsome and another man to the ground.

Mr Spong told the court he was devastated by the death of his friend.

Mr Spong did not comment on the jury's decision as he left the ACT Supreme Court. ( ABC News )

Prosecutor Margaret Jones told the jury there was no doubt Mr Spong was guilty of culpable driving.

She said there were five people on the back, and he was responsible for their safety.

"There was no warning and he did not look around to see where everyone was," she said.

"It was improper driving that put other people in harm's way and it had tragic consequences.

"It was not an accident. It was intentional and deliberate driving."

But Mr Spong's lawyer Steve Whybrow told the jury it was a momentary lapse.

"This is a man who was not driving like a ratbag," she said.

"He consciously tried to spin the wheels like he'd done many times before.

"It was not a risk from his perspective."

The jury retired on Friday and resumed this morning.

But after only 15 minutes a verdict was reached.

In an unusual move, the jury used its discretion to also find Mr Spong not guilty of an alternative charge of negligent driving, even though he admitted to the charge — meaning he walked free.

Following the death, festival organisers banned riding on the back of utes, which was previously rife at the event.