But the man's lawyers said he was trying only to "chirp" or cause a minor spin of the truck's wheels. They said Mr Spong, 33, is devastated by the death of his friend Luke Newsome, 30, and had taken responsibility for it by admitting he had driven negligently.

While Mr Spong, on trial in the ACT Supreme Court this week, has admitted he drove negligently, prosecutors have pressed the more serious charge of culpable driving. Namely, that Mr Spong was negligent by failing "unjustifiably and to a gross degree" to observe the standard of care that a reasonable person would have in all the circumstances. To that charge he has pleaded not guilty.

On January 5, 2017, the festival's first day, Mr Spong was lapping the cruise route, a ring road around Canberra's Epic showground where the annual car festival is held. On the back of the truck's flat bed tray was his wife and his best friend, Mr Newsome, and two other friends.

Prosecutor Margaret Jones said Mr Spong had depressed the clutch on the manual transmission truck and then accelerated, revving the engine. He then lifted his foot from the clutch. Ms Jones said that what Mr Spong hoped would happen when he dropped the clutch was that the engine power would transfer to the back wheels and spin so fast they would lose traction.

He wanted to do a burnout, she said. "That was the plan."

She said he did not tell the five people on the back what he was going to do. She told the court that the "flat bed" of the tray had no railings.

But what happened when he released the clutch, as Mr Spong told police, the back wheels "bit" into the bitumen and the truck suddenly launched forward.

Mr Newsome and another man were thrown from the tray. While the other man was able to get up, Mr Newsome fell unconscious and briefly stopped breathing. He died the next day in hospital; the cause of his death was severe closed head injury.

Ms Jones said while it was difficult to not feel sadness in a case like this, she asked the jurors to exercise their role dispassionately, and put aside their emotions.

Summernats director Andy Lopez was the first called to give evidence. He told the court burnouts were prohibited on the cruise route, and security had a three level rating system to categorise the severity of the prohibited driving behaviour. Punishment ranged from "grounding" the car from an hour or more to evicting the patron from the event, he said.

The court heard there was a special area for burnouts, where drivers had to wear helmets, fire suits and cars were allowed only one passenger.

But defence barrister Steven Whybrow, who is instructed by Jacob Robertson of Sharman Robertson Solicitors, played to the jury multiple YouTube videos - including the one embedded below - of patrons doing burnouts and power launches in the cruise area, particularly on a stretch called Tuff Street, where concrete barriers separated the patrons from the cars.

Addressing the jury at the opening of the trial, Mr Whybrow said Summernats was a "special little world, where quite a lot of the rules that apply to cars don't apply". He said even with the rules inside the Summernats festival, burnouts were endemic outside the designated burnout area.

Mr Whybrow told the jury Mr Spong was trying only to "chirp", or perform a minor wheel spin, like many other drivers at the festival, though many were doing worse manoeuvres.

"At no stage was he attempting to do a burnout," Mr Whybrow said.

What had happened was a tragedy but it was a lapse, he said. He pointed to the man's police interview, in which Mr Spong spoke about not accounting for the weight of five people on the back of the truck.

Mr Whybrow said the issue for the jury was whether in all the circumstances the man's actions met the threshold for the more serious charge of culpable driving.

The trial continues before Justice Chrissa Loukas-Karlsson.