Listen to the full documentary here
The number of deaths on New Zealand's roads has been on the rise since 2013. This year's toll is now 329 - one higher than the total number of deaths for the whole of last year. For every road death, 10 others suffer serious injury, and sometimes life-long consequences. A similar trend is plaguing other countries. But does anyone have the answer?
Weekend after weekend, ambulance crews and police officers find themselves at crashes where people have been killed or seriously injured.
National manager of road policing Superintendent Steve Greally says nothing can prepare you for the sight and sound of a crash.
"The first time I went to one of these scenes, it wasn't a fatal crash, but there was serious injury involved, and there was screaming from people who couldn't cope and there was nothing we could do for them ... it's the pain, it's the trauma, it's the shock that you see and hear".
Even worse than witnessing that suffering first hand, he said, was having to tell someone their loved one was not coming home.
"Quite literally you're about to ruin someone's life."
Mr Greally remembers the first time he had to shoulder that task, about a month after he joined the police. His sergeant told him to knock on the door, identify the person and then just spit it out as any hesitation would make it impossible to get the words out.
"I did exactly what my sergeant said, I just spat it out. I said, 'I'm sorry but your husband's been killed in a car crash,' and I saw it right there, her world imploded right before me."
Since 2013, officials have had to make more of these visits to deliver the bad news. Between 2014 and 2016, the New Zealand road toll increased by 12 percent. We're also not alone, with the Ministry of Transport listing New Zealand among 19 other OECD countries that have experienced an increase in fatalities.
To try to understand the reasons behind this upward trend, the Ministry of Transport commissioned an independent analysis of the road toll that has just been released. However, no dramatic findings emerged. The report, by Deloitte, pointed to the increase in kilometres travelled and the increased chance of a crash resulting in death or injury. It also highlighted the disproportionate increase in motorcycle accidents.
But its key messages gave weight to the ongoing conundrum over what has caused the toll to head upwards.
"The factors that cause crashes and cause injuries are many and varied. For this reason, it is difficult to understand all the variation in road trauma. In this study, about a third of the short-term variation could not be explained by the factors investigated.
New Zealand Transport Agency's national director for safety Harry Wilson said that as New Zealand emerged from the global financial recession, more people had been driving, and vehicle numbers have increased. An upturn in the economy has also meant more trucks on the road. The rate of heavy vehicles being at fault remained the same, he said, but the forces involved meant a bad outcome in any accident involving a truck.
He also noted the increase in road deaths where people weren't wearing a safety belt, but taking into account all those factors was still not enough to explain the trend.
When the stakes are so high, why are New Zealand drivers not taking greater care to ensure they don't end up as a road toll statistic?
At Waikato University's Transport Research Group, Samuel Charlton studies why drivers behave in the way they do. He said New Zealand drivers were known to be competitive, and described New Zealanders as one of the "world leaders" in the desire to race away from the traffic lights and beat everyone else, a trait that is coupled with an urge to get in front of other cars.
But Mr Charlton wants New Zealanders to learn to take responsibility for their actions, as many drive almost 'automatically' and blame others when something goes wrong.
"There's a tendency to say 'well, this is just a terrible road' and get on with their day, but drivers have a responsibility, they need to understand it's not all the other drivers fault.
"We bear some of the responsibility, and very often we are intolerant of other road users - whether it's pedestrians, cyclists or whatever - and that's got to change."
Sometimes, however, it really can be a terrible road.
On the AA's election wish list, improving was roads high up. General Manger of Motoring Affairs Mike Noon said they had asked for two-star quality high speed rural roads to be upgraded to three-star quality at a rate of 150kms a year.
"That can halve the number of deaths and serious injury ... so we also want more investment in rumble strips and road dividers," he said.
Another other big push from the AA is for used cars to be made to display a safety rating, a change the New Zealand Transport Agency is also behind.
However, achieving that figure would mean almost doubling the number of kilometres of road upgraded every year, the AA said. It also wants that work to be accounted for, to make sure the money is being spent as intended, with a measure available to gauge the improvement.
As much as every death on the road is a tragedy, however, the legacy of traffic accident injury can also be life-long. The generally accepted measure is that for every person who dies on the roads another 10 are seriously injured, which means this year more than 3000 have been badly hurt and possibly permanently disabled in road accidents.
The Major Trauma Network is trying to reduce the long-term effects of such injuries, as well as cutting the death rate.
Its clinical leader Ian Civil is a trauma surgeon at Auckland City hospital, and said while everyone involved in helping those seriously injured in road accidents has been doing their level best, taking them to the best-suited hospital for dealing with their injuries - rather than the closest - could significantly improve their chances of survival.
He said the Australian state of Victoria had introduced such a system, and not only had the number of deaths dropped by a third compared to what it was in the '90s, there had been an improvement in the quality of life for survivors.
Mr Civil said New Zealand's geography would always pose a challenge when it came to transporting those hurt in an accident, but he was still optimistic that it would be possible to achieve a 20 to 30 percent reduction in the number of people who die after major trauma.
Insight is on iTunes: subscribe and give us a review
Or head to Spotify or wherever you get your podcasts