IR-01-25-41908
15 January 2026
Joel Pitt
[FYI request #32884 email]
Dear Joel
Thank you for your Official Information Act 1982 (OIA) request received 17 November
2025 in which you asked:
I believe it is in the public's interest - and I am requesting under the OIA - the
purported detection thresholds, sensitivity, accuracy, specificity, false positive
and false negative rate for the DrugWipe 3S against each substance it can
detect.
New Zealand Police set up a Scientific Panel in 2025 to provide expertise and advice on the
threshold (cut-off concentration level) to detect recent use of specified impairing drugs in a
driver’s saliva (i.e. oral fluid). This included a review of proposed laboratory thresholds by
an independent scientific reviewer to verify that the thresholds met the legislative
requirements. These drugs are found in Schedule 5 of the Land Transport Act 1998.
The thresholds set are indicative of the recent use of the respective drug, with recent use
being a time period associated with potential impairment. The thresholds are set to exclude
past use and passive exposure. Each threshold has been set after considering current
scientific evidence, including drug concentrations reported in saliva after recent use, the
period of likely impairment and the length of time required to eliminate the drug from saliva.
The
Securetec DrugWipe 3 S device to be used for roadside drug screening can detect
the presence of THC (cannabis), methamphetamine (meth), MDMA, and cocaine in saliva
at or above the threshold that indicates current and recent use.
The thresholds for each drug have been specified in the Land Transport (Approved Oral
Fluid Screening Device) Notice 2025. A copy of the Notice is publicly available here:
https://www.legislation.govt.nz/regulation/public/2025/0246/latest/LMS1539637.html
The specified thresholds for roadside testing are:
Qualifying drug
Threshold (ng/mL)
Cocaine
50
MDMA
50
Methamphetamine
50
THC (cannabis)
15
A driver who tests positive on a roadside screening test is required to provide a saliva
sample for laboratory analysis. Al 25 listed qualified drugs in Schedule 5 of the Land
Police National Headquarters 180 Molesworth Street. PO Box 3017, Wellington 6140, New Zealand.
Telephone: 04 474 9499. Fax: 04 498 7400. www.police.govt.nz
Transport Act 1998 wil be tested for in the laboratory. The thresholds for laboratory
testing are specified in the Land Transport (Concentration Level of Listed Qualifying
Drugs) Notice 2025. A copy of this Notice is publicly available here:
https://www.legislation.govt.nz/regulation/public/2025/0247/latest/LMS1538003.html
Please note that roadside drug screening devices are set at a higher threshold than the
laboratory because roadside devices use an immunoassay technique that detects the
specific drug, meaning the actual drug concentration may be lower than the roadside
device threshold.
The thresholds have been set to also reflect that there may be some loss of the drug
during collection and transportation to the laboratory. The higher threshold assists with
eliminating negative results from the laboratory that would often occur if the threshold for
the roadside device and the laboratory were the same.
Drivers should be aware of the risk of mixing drugs or prescription medicines and/or
taking with alcohol.
In regard to the accuracy of the devices, as part of the procurement process, al roadside
drug testing equipment to be used by Police was independently verified in New Zealand
or Australia. Accuracy verification confirmed the equipment met the Australian and New
Zealand Standard for oral fluid testing (AS/NZS 4760) in respect of false positives and
false negatives.
Testing involved checking al positive drug screening tests in the laboratory. A 5% false
positive rate was found in cases where drugs were present but below New Zealand’s legal
threshold. These cases would not result in an infringement. No false negatives occurred.
In New Zealand, a driver must test positive at or above a specified threshold. This
threshold indicates recent use and excludes passive exposure.
A driver is only forbidden to drive for 12 hours if both roadside screening tests are
positive. An infringement notice is only issued if a positive laboratory test is at or above
the legal threshold.
Separately, I am also requesting how much each test is costing the tax payer.
Information related to the costs of each test is withheld under section 9(2)(b)(ii) of the OIA
as making available the information would be likely unreasonably to prejudice the
commercial position of the person who supplied or who is the subject of the information.
Police wil soon publish more information on our website about what drivers can expect
from the drug driving testing.
I trust this information is satisfactory in answering your request. If you are not satisfied
with the way I have responded to your request, you have the right under section 28(3) of
the OIA to ask the Ombudsman to review my decisions. Information on how to do this is
available onlin
e at www.ombudsman.parliament.nz.
Yours sincerely
Superintendent Steve Greally
Director: Road Policing
