A crash in which an overcrowded van holding a dozen unrestrained youths, some sitting on a couch, being driven by a tired driver who was texting, was "almost inevitable'', a coroner says.
All 12 occupants were thrown from the van when it crashed into a bank and rolled, south of Rotorua in the early hours of July 17 2010.
One of the front seat passengers, Jesse Bleu Howe, a 17-year-old student, died from his injuries.
At an inquest into his death, Rotorua Coroner Wallace Bain said the group was driving back to Rotorua after attending a party in Taupo.
The van had seats for only five people, but the rest sat on a couch and a large speaker box.
The driver, Aaron Gourlay was tired but decided to continue the journey and drink a V energy drink as well as taking caffeine pills, No Doz to keep awake.
Coroner Bain said the evidence established that Gourlay's phone contained details of text conversations in the 13 minutes before the crash.
Bay of Plenty road policing manager Inspector Kevin Taylor told the inquest he could not say conclusively if Gourlay was texting at the time he lost control, but "the number of texts and timing of those texts show a pattern of behaviour up to within a few minutes of the crash occurring''.
"Given the timing the police view is that the driver has been texting while driving between Reporoa and Rotorua.''
Police also noted defects on the vehicle, including a badly worn front left tyre which had been fitted the wrong way round on the rim. It was secured by only three of the five wheel nuts required.
None of the occupants were wearing seatbelts and all were thrown onto the road or into a ditch when the vehicle rolled.
The road was wet at the time, and although Gourlay was not speeding, Coroner Bain said he was travelling too fast for the conditions.
"Although alcohol was not a factor in the crash, speed, driver inexperience, poor weather conditions, driver fatigue and use of a cellphone while driving were all contributing factors.''
Police told the inquest any one of those factors on their own could have caused the crash, let alone a combination of eight or nine of the serious breaches in driving.
Coroner Bain said danger signals were there, yet the journey continued in atrocious weather with the "almost inevitability of an accident''.
Gourlay was convicted of dangerous driving causing injury and death at the Rotorua District Court and sentenced to six months home detention, community work and was disqualified from driving for two years.
He told the coronial inquiry the decision to drive was one he would have to live with for the rest of his life.
"The remorse I feel can never be expressed in words.''
Coroner Bain asked that his findings be forwarded to the ministers of transport, education and youth development, and asked they support a youth education campaign into the dangers of driving while distracted, including the use of cellphones, fatigue, overloading vehicles, wearing seatbelts and driving to the conditions.