Was a father egging his sons on to race by encouraging speeding and dangerous driving, leading to a double fatal collision, or is he a victim left traumatised by an accident he had no part in?

That is the question a jury will face tomorrow when they are tasked with deciding what Mark Nicholl snr’s intentions were on the night one of his sons and a family friend died and two of his other sons were seriously injured.

The Crown allege Nicholl snr had encouraged the race, while his defence team says he did not encourage it in any way and had “quite clearly” backed off while it was taking place.

The 55-year-old has been defending charges related to the September 25, 2021, crash in a trial at Christchurch District Court, which began on Monday.

His son Mark Nicholl jnr, 30, and family friend William Clark, 29, were both killed in the crash while another son, Jayden Nicholl, was seriously injured and a third son, Shanan Nicholl, suffered a traumatic brain injury.

Mark Nicholl jnr had been with family and friends at a pub before the street race which killed him. Photo / Facebook

Shanan originally faced the same charges as his father - two charges of being a party to dangerous driving causing death and one of dangerous driving causing injury - but was considered unfit to stand trial due to his brain injury and was discharged.

Nicholl snr’s nephew Ricky Nicholl has pleaded guilty to the same charges Nicholl Snr faces, as well as a charge of attempting to pervert the course of justice by swapping seats with passenger Matthew Gibbons following the crash.

• 'It's not good, don't come over': Dad saw fatal crash, drove home instead of checking on sons

The trial has heard that Nicholl snr had finished dining with family and friends at a bar in Christchurch when he and his family members allegedly began street racing.

The group, travelling in a Jeep, Holden, Subaru and a Mazda, convoyed down Main South Rd towards the intersection of Halswell Junction and Shands roads when the Subaru spun out of control and collided with a ute.

Today, the Crown and Nicholl snr’s defence team gave their closing submissions to the jury.

Tributes at the scene of the double fatal crash in Christchurch that happened in September 2021. Photo / George Heard

Prosecutor Deirdre Elsmore claimed Nicholl snr encouraged Shanan to speed that night and “excited” him to the point he continued to speed and race his cousin, which led to him losing control of the Subaru and colliding with a ute, causing the deaths.

Elsmore said the incident brought trauma not only to the families who have lost loved ones but also to the couple driving the ute, pointing out that if not for the sturdiness of their vehicle they could have faced a different outcome.

She said the collision was caused by excessive speed, and that speed could be attributed to Nicholl snr who was following the Subaru in “hot pursuit” moments before the crash.

Elsmore said Nicholl snr admitted to police he was going over the speed limit and passed one of the boys “just to have them on”.

This clearly sent the message to his sons that “it’s all on and dad’s on board”, Elsmore said.

By the time Nicholl snr “lurched forward” in his Holden, Elsmore said “the job was done” and Shanan had all the encouragement he needed to race.

She said it was that encouragement that made Shanan rev his engine at the traffic lights and “fly down” the intersection, continuing to speed until he lost control and crashed.

Elsmore asked the jury to hold Nicholl snr responsible for the deaths and injuries caused that night.

But defence counsel Joshua Lucas told the jury Nicholl snr did nothing wrong.

Lucas said his client was not the one who lost control of his car and crashed, nor did he encourage his son to speed in any way.

Lucas said it was the Subaru, driven by Shanan, and the Jeep, driven by his cousin Ricky, that were racing, while Nicholl snr was hanging back in his Holden and letting the others overtake him.

Lucas questioned why the Crown did not call evidence from anyone involved in the convoy that night, stating they were the only ones who could confirm what had occurred before the group left the pub.

He said this was the only way to know if there were any discussions of racing.

Pointing to what he argued were “gaps” in the Crown case, Lucas told the jury they could not be sure beyond reasonable doubt that his client was guilty.

Lucas said Nicholl snr went into shock after the crash and acted on instinct when he went home without checking on them.

He acknowledged some people may have rushed to the crash but told the jury everyone reacted to shock and trauma in different ways.

Lucas said Nicholl snr’s willingness to engage with police after the crash showed he was trying to help, and he was honest and compliant despite the “long and gruelling” interview.

He said Nicholl snr was not seen doing any burnouts or spinning his wheels and there were points in the CCTV footage that showed his brake lights on or him going around corners at a much slower pace than the rest of the group.

“Mr Nicholls did not contribute to the death of his child, the injury of his other children, and the death of their friend, he is not guilty,” he told the jury.

Judge Gerard Lynch will give the jury a summary of the case tomorrow before they retire to deliberate.

Emily Moorhouse is a Christchurch-based Open Justice journalist at NZME. She joined NZME in 2022. Before that, she was at the Christchurch Star.