Flaws in drug driver tests
JOANNA VAUGHAN, POLITICAL REPORTER
October 27, 2007 02:15am
MORE than one in 20 positive results from roadside drug-driving tests have later been overturned by laboratory checks.
A Parliament report on the first year of drug driving laws says about 6 per cent of the roadside tests have been proved wrong.
It says the rate is concerning and recommended police explore ways to ensure improved performance of their equipment.
The laws, which came into force on July 1 last year, give police the power to test drivers for the illegal drugs cannabis, methamphetamine and ecstasy.
In a three-step process, an initial swab is taken from the tongue which, if it shows a positive reading, is followed by another test in which a sample of saliva or blood is tested. If this records a positive reading, the sample is analysed in the laboratory.
Assistant Commissioner Grant Stevens said: "This is one area where we can improve.
"We would like our processes to be as close to 100 per cent as possible . . . " he said. "We are confident we will be able to reduce the incidents of false positives substantially through the review of our equipment."
If a driver does test positive to one or more drugs, they are forbidden from driving for up to 24 hours, but a fine is not issued until the results are confirmed by a laboratory.
In the first year, more than 10,000 drivers were tested and almost 300 recorded a positive reading. Of these, 127 tested positive to methamphetamine, 77 to cannabis, 64 to both cannabis and methamphetamine, 10 to both ecstasy and methamphetamine, nine to ecstasy, five for all three drugs and two to both cannabis and ecstasy.
Opposition police spokesman David Ridgway said the tests should always be accurate.
"The statistics released in the report show there are people out there who are driving under the influence of drugs, so if you are going to have tests, then they need to be accurate and as fail proof as possible," he said.
"It seems strange drugs would be detected at the roadside, but not in the lab, so this has to be addressed."
Road Safety Minister Carmel Zollo said while she was happy with the first year of the operation, she would present the 18 recommendations from the report to Cabinet.