The government appears to have spent a fraction of the money it promised to invest in a highly effective methamphetamine programme.
Early evaluations of Te Ara Oranga found a 34 percent reduction in harm from offending among its participants and a return of between $3 and $7 for every $1 invested.
In the lead-up to the 2020 election, former prime minister Dame Jacinda Ardern promised to expand the programme to a further 4000 people at a cost of $38 million over the three-year Parliamentary term.
Figures released to RNZ under the Official Information Act show as of June 2023, the Health Ministry had spent less than a fifth of this promised investment.
Spending had scaled up over time with $1.2m spent between November 2020 to June 2021, $2.2m spent between July 2021 and June 2022 and close to $3m spent between July 2022 and June 2023.
National's justice spokesperson Paul Goldsmith said it was a missed opportunity.
"It's very disappointing to think of the many lives and many families that could have been helped by this programme, not just in Northland but throughout the country, if it had been rolled out.
"This is a programme that works well and they just haven't got around to scaling it up like they said they would."
Health Minister Ayesha Verrall said some money would have been spent by police, as it was a joint venture, but the pandemic and weather disruptions had slowed the rollout of the programme.
"A proportion of that spend will be spent by police so to understand the total spend you'd have to look across both portfolios.
"As I've said before, there was a delay in the rollout of the programme to parts of the central North Island and that has led to the underspend."
National is yet to make any concrete promises itself in regards to what it would do with the programme but Goldsmith said his party would invest in what worked.
"So long as this programme continues to do well and have an impact on the lives of those who go through it, we will support it."