He had been at a party with friends before leaving after midnight to walk to his caravan nearby, where he lived along the highway on land occupied by a childhood mate.
When Arrowsmith left, he was drunk and angry after having a fight with that longtime friend at the party.
Within the hour, he was dead.
Now, Coroner Mary-Anne Borrowdale has released her findings into his death, in which she stamps out speculation Arrowsmith had been assaulted or killed and then placed on the road.
“There is no evidence to support these speculations,” she said in her ruling, released this month.
“I find that Mr Arrowsmith likely died as the result of being struck by two heavy trucks while lying in a prone position across the highway.”
Her findings said Arrowsmith had been living in the caravan with his partner since around May 2020.
In the days preceding his death, Arrowsmith had disagreed with his friend about whether he was meeting his obligations to help on the land, and also about his partner.
The coroner said records show he felt despairing at the time with a degree of suicidality but there was no record he had ever attempted suicide.
Around 7pm on August 28, 2020, Arrowsmith and his partner drove to a neighbouring house on the highway to attend a party.
He drank three beers before he arrived and had a further 12, and shots of spirits, while there.
During the night, a “physical altercation” occurred between Arrowsmith and his friend, with the party’s host also becoming involved.
Arrowsmith was described as “raging,” something he was said to do when coming down from drugs, the findings stated.
Sometime after midnight, Arrowsmith left and began walking to his caravan.
He was seen by a motorist at 1.09am walking on the left side of the road, about 50 metres from the party, “gesticulating wildly and yelling.”
Moments later, a truck driver saw him on the right side of the road, with his arm out in a hitch-hiking position.
That was the last sighting of him alive.
At 1.21am a truck struck Arrowsmith lying across the centre line of the road. There was no time for the driver, who at the time did not know what he had hit, to take evasive action.
Another motorist passed by moments later and phoned police.
At 1.39am a second truck hit Arrowsmith. The driver was also unable to take evasive action.
At Murchison, the nearest town, the truck drivers stopped and discussed their concerns. They too rang police.
Arrowsmith’s body was located by other motorists, around 240m from the party.
A forensic pathologist found no specific evidence of prior impact as a standing pedestrian struck by a vehicle. He also found no evidence of prior assault, nor of any lethal violence that was not attributable to the runovers.
Toxicology testing detected alcohol, cannabis and methamphetamine in Arrowsmith’s system.
The coroner said it was not known why Arrowsmith was lying face-down on the road.
“His high blood alcohol level was thought to be a contributing factor. Methamphetamine and cannabis tended to accentuate the effects of alcohol consumption.”
During investigations into his death, police interviewed a number of people who were close to Arrowsmith and connected to his death.
The coroner reviewed all evidence and said it was clear some people held suspicions that “he came to be in the roadway as a result of foul play.
“When tested, people holding these views have acknowledged that they suspect others, but have no relevant evidence to offer,” she said.
The coroner was also not prepared to conclude Arrowsmith had put himself on the road with the intention of causing his own death, stating compelling evidence was required to make a finding of suicide.
“That is a distinct possibility, but there is insufficient evidence to that effect.”
Coroner Borrowdale, who was bound to make her findings on the standard of likelihood, said there was no good evidence of foul play, natural disease, or prior accident or assault.
“In my opinion, the most likely sequence of events is that Mr Arrowsmith, upset and wandering at night, affected by alcohol and illicit substances, has fallen or suffered a collapse onto the roadway, at which stage he was run over and killed by one or both of the trucks.”
No recommendations were made.
Tara Shaskey joined NZME in 2022 as a news director and Open Justice reporter. She has been a reporter since 2014 and previously worked at Stuff where she covered crime and justice, arts and entertainment, and Māori issues.