New Zealand is introducing a new random roadside drug-testing system under the Land Transport (Drug Driving) Amendment Act 2025. From December 2025 (starting in Wellington and expanding nationwide by mid-2026), Police will be able to stop any driver and carry out a quick saliva (oral-fluid) test without needing suspicion, similar to alcohol breath testing.
Initial saliva test: A tongue swab screens for THC (cannabis), methamphetamine, MDMA, and cocaine.
Second test & 12-hour ban: If the first test is positive, a second test is done. A second positive result leads to an immediate 12-hour driving ban.
Lab testing: The initial sample is then analysed in a laboratory for up to 25 specified drugs. If a drug is confirmed, the driver receives an infringement notice (fine + demerit points).
The test detects presence, not impairment. Drugs such as cannabis can remain detectable long after the effects have worn off.
Medicinal cannabis and some prescription medicines (e.g., benzodiazepines, opioids) may result in a positive test.
A medical defence is available but only after an infringement is issued, it cannot be used at the roadside. Please see this page on the NZ Police website for more information on the medical defence process.
For detailed information on the law, including a full list of the drugs and potential penalties, please refer to the official resources from NZ Transport Agency Waka Kotahi, the New Zealand Police, and the Ministry of Transport.
The New Zealand Drug Foundation also has more helpful information on these changes.
NZ Police have specified the detection device.
