A Bill that would strengthen police powers to tackle drug driving has been lodged.
National MP Alastair Scott's Bill would allow police to stop drivers "anytime, anywhere", as they can for alcohol testing.
The drivers then may be tested for cannabis, MDMA and methamphetamine.
Scott said the current law doesn't do enough to deter drug-impaired people from getting behind the wheel. Police must have good cause to suspect that a driver is impaired by drugs before requiring them to stop and take a behavioural test, like walking heel-to-toe in a straight line.
"Too many fatal crashes involving drugs have highlighted the need to crack down on those who get behind the wheel while under the influence of illegal substances," Scott said.
"That's why I've lodged the Land Transport (Random Oral Fluid Testing) Amendment Bill to establish an effective police roadside testing regime to better deal with drug driving.
"At a time when the roads are heavy with traffic from holidaymakers returning home and tourists making the most of the New Zealand summer, the risk of drug-impaired drivers causing serious injury or fatal crashes increases significantly."
He added: "Police roadside testing is a much stronger and more visible drug driving enforcement measure, which will help deter people from driving while under the influence of drugs. It will also improve police's ability to catch [them] before they cause a crash.
He said advances in technology has made roadside testing for drugs much more practical.