A coroner has warned of the dangers of driving while impaired by drugs after reviewing nine fatal vehicle crashes and finding cannabis use was implicated in six of them.
The stark warning came in the coronial findings which examined the death of Thomas Jacob Goodman who crashed driving home from a work gathering on the night of November 29 last year.
Goodman, 29, had just started working as a farmhand at a South Canterbury farm when he and some workmates stayed behind for a few drinks.
His employer supplied alcohol and a barbecue was put on.
When Goodman went to leave at around 10pm, his boss asked him if he was "okay to drive" and offered him a bed for the night. He thought he'd had around three to four beers over the evening – six at the most.
Goodman said he was fit to drive and headed home, a short distance away.
His boss texted him around 20 minutes later – as he did with most of his workers - to check that he'd arrived home safely.
But he never got a reply.
The next morning Goodman's partner phoned one of his mates concerned that he had not come home.
The mate drove down Clarkesfield Rd at Elephant Hill, south of Waimate, looking for him and found skid marks leading off the road and down a bank.
He saw Goodman's wrecked Foton Tunland 4WD ute at the bottom of the slope.
The friend then found his body about halfway down the bank. He was obviously dead.
The police serious crash unit found that Goodman must have drifted across the road, over-corrected, and gone off the road.
A post-mortem concluded that he died from blunt head trauma.
He was found to be almost five times the legal drink-drive limit while also testing positive for cannabis and its constituent element tetrahydrocannabinol (THC).
Coroner David Robinson found that Goodman's death could have been avoided by "adhering to the basic rules of road safety" and wearing a seatbelt, not drinking, or taking drugs.
On the day the coroner prepared his finding, he reviewed nine separate motor vehicle fatality cases.
"Cannabis was implicated in six of those nine," Coroner Robinson wrote in his findings released today.
"If that sample is truly representative of the proportion of fatal driving cases where cannabis is implicated, the picture painted must be of real concern."
Coroner Robinson made no recommendations, adding: "The road safety messages are well known."
He extended his deepest condolences to Goodman's family and friends.