On December 28, 2024, a modified trailer hired from a Northland tool hire firm fishtailed and collided head-on with a family car, killing 35-year-old Mandy Mackenzie.
Kerikeri Tool Hire 2015 Limited was sentenced in the Kaikohe District Court on Monday, after pleading guilty to a charge under the Health and Safety at Work Act. Judge Brandt Shortland fined the firm $140,000 and ordered it to pay $333,833 in reparation to the victims.
The fatal crash occurred as customer Mane Adams drove south at 70km/h in a 100km/h zone, returning the twin-axle trailer and an attached mini loader to the business. Near the Waipapa Stream bridge, the trailer began to fishtail around a sweeping left-hand bend, crossing the centre line and striking Mackenzie’s vehicle.
Mackenzie, a mother of three boys, died at the scene. Her husband and four other passengers were in the car; one passenger sustained serious injuries requiring multiple surgeries, while others sustained minor injuries. Adams also sustained minor injuries in the collision.
WorkSafe Investigates Trailer Alterations That Caused Imbalance
WorkSafe launched an investigation following a Serious Crash Unit re-enactment that revealed irregularities. Investigators found that approximately five years earlier, the company had extended the trailer’s ramp-locking bars to allow the mini loader to sit further back on the deck.
WorkSafe lawyer Alexandra Simpson told the court, “It was reasonably practicable for Kerikeri Tool Hire to have ensured that the trailer hired to tow the mini loader was safe or safe to use.”
Because of the modifications, the trailer’s overall balance and weight distribution were altered, making it impossible to place the loader so that proper downward pressure was exerted on the tow-ball. Consequently, the center of gravity shifted, rendering the trailer unstable during ordinary travel and heightening its susceptibility to fishtailing.
The company informed WorkSafe that the work was carried out by an on-site mechanic whose background was in welding. While underinflated tyres were identified as a secondary factor, WorkSafe said even if they were inflated correctly the downforce pull would have remained.
Judge Shortland noted the company had fully cooperated from the beginning, entered an early guilty plea, and had not been in the courts before. “Whenever there is a death involved it is tragic for all involved from the family and the knock-on effect can never be measured,” Judge Shortland said.
Industry Regulation Concerns Raised
Defending the business, lawyer Ellie Harrison argued that the tragedy highlighted broader issues. “No particular qualification is required to hire or tow a trailer and heavy machinery; anyone with a driver’s licence can do so,” Harrison said. “The tragedy partly demonstrates that failure to regulate.”
Harrison suggested that further guidance from NZTA would have been helpful and that it may be time for NZTA to act through licensing or mandatory checks. She also suggested the issue could be considered further by the coroner.
WorkSafe regional manager Brad Duggan emphasized that businesses should assess any modification for its effect on safety before equipment goes out the door. “When a business changes a piece of equipment and then hires it out, it takes on responsibility for making sure it is safe for the people who use it and everyone else they encounter while it’s being used,” Duggan said.
