Millie McCutcheon was driving her father's Alfa Romeo 146 on State Highway 27 at Patetonga, in the Hauraki district, about 3.50pm on August 31 last year.
She failed to notice a truck and trailer unit in front of her had slowed almost to a complete stop at the Tramline Rd intersection and did not brake or take any evasive action.
As a result, the Alfa Romeo crashed into the rear of the heavy trailer, prosecutor Sergeant Ross Hutton told the Dunedin District Court yesterday.
The front seat passenger, Felicity Paige Wren, was severely injured and died at the scene.
McCutcheon could not provide any explanation for her inattention, Sgt Hutton said.
Alcohol was not a factor and she had held a driver's licence for about three years.
She admitted a charge of careless driving causing the death of Ms Wren and was remanded by Judge Michael Crosbie for sentence next Tuesday.
Counsel Anne Stevens said the two young women were best friends and had been flatting together and attending Massey University for three years.
McCutcheon had attended Otago Girls' High School School, was a good sportswoman and a surf lifesaver.
She was ''nothing but of good character'' and the death of her friend had had a devastating effect on her, Mrs Stevens said.
She wished to undergo a restorative justice meeting with the dead woman's family.
