The car involved in the fatal crash in Thames this morning should not have been on the road, having been found unroadworthy just hours before the driver lost control and crashed through three fences, police say.
An 18-year-old male travelling as a back seat passenger died when the Holden Commodore left the road and overturned this morning about 4.30am.
The driver and other three passengers received minor injuries.
Initial assessments of the crash site on Parawai Road this morning indicated the 37-year-old female driver lost control of the vehicle and left the road, crashing through three fences, police said.
Earlier this morning, about 1.30am, officers stopped the same car being driven by a 31-year-old male who failed a breath alcohol test and the vehicle was found to be unroadworthy.
"It was issued a non-operational order and the keys were taken by Police so it should not have been on the road at all, let alone being driven at the time of the crash," Waikato District police commander Superintendent Win van der Velde said.
This morning's crash brings the number of people killed on Waikato roads this month to two, and it is the sixth fatal or serious injury related crash attended by members of the Waikato Serious Crash Unit this week.