44 Bowen Street
Private Bag 6995
Wellington 6141
New Zealand
T 64 4 894 5400
F 64 4 894 6100
www.nzta.govt.nz
22 January 2026
Hayden
[FYI request #33252 email]
REF: OIA-20630
Dear Hayden
Request made under the Official Information Act 1982
Thank you for your email
of 13 December 2025 requesting information about roadside drug tests
under the Official Information Act 1982 (the Act). I note that al parts of your request, except for section
2, were transferred to other government agencies as the information sought was more closely aligned
with their functions.
SECTION 2: STATISTICAL BASIS AND METHODOLOGY
(e) Al analysis, reports, or calculations distinguishing between:
•
Road fatalities where drugs were present in the deceased driver's system
•
Road fatalities where drugs were determined to have caused or contributed to the crash
(f) Specific breakdown of the widely cited "30% of road deaths involve drugs" statistic, including:
•
How many involved THC alone vs. THC combined with alcohol or other drugs
•
Causality analysis (presence vs. impairment vs. crash causation)
•
Source data and methodology
The fol owing documents fal within the scope of your request and are enclosed:
• Attachment 1 - Crashes 30 percent road deaths involve drugs CAS data
The reference to 30 percent of road deaths involve drugs appears to have come from this website
page:
www.nzta.govt.nz/safety/driving-safely/illegal-drugs. The website refers to crash statistics for the period 2019- 2023. Therefore, we have provided the most
current data for the period 2019-2023. Due to the lag in police reporting timeframes and updates to NZ
Transport Agency Waka Kotahi (NZTA), the information in the Crash Analysis System (CAS) has been
constantly updated since the original data was pulled. The numbers in this dataset wil differ from
those in the original data set.
In line with NZTA policy, this response wil soon be published on our website, with personal
information removed.
If you would like to discuss this reply with NZTA, please contact Ministerial Services by email to
[NZTA request email].
Yours sincerely
Sam Russell
Manager Ministerial Services
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