The 1998 murder of the Ashburton schoolgirl remains one of New Zealand's most high-profile cold cases.
Kirsty disappeared on December 31, 1998, while walking the family dog Abby on the banks of the Ashburton River.
The day after Kirsty went missing, the family's dog Abby was found tied to a tree near the river, and the teen's underwear was nearby.