The Southern police district has recorded the largest number of drugged drivers in the South Island, with a Dunedin driver who drove into four parked cars the latest allegedly caught under the influence behind the wheel.
Police have caught 568 drugged drivers between November 2009 and February, with 51 of those recorded in the Southern district - the fourth-highest rate in the country after Bay of Plenty (116), Waitemata (70) and Central (63).
The district recorded more drugged drivers than Canterbury (32) and almost twice as many as Tasman (26).
In the latest incident, police were called to Maclaggan St, Dunedin after a driver drove into four parked cars on Thursday.
The 22-year-old unemployed woman returned a negative drink-driving test and police tested for drug impairment.
Southern district road policing acting manager Senior Sergeant Steve Larking said police in the district were "proactive in identifying impaired drivers who aren't affected by alcohol but by a controlled drug".
He said a number of apprehensions were the result of checkpoints, attendance at crashes and information received from the public about poor driving.
"Drugged driving is recognised as an issue throughout the country and was the reason behind the introduction of the compulsory impairment test [CIT] legislation.
"We know that alcohol and drugs feature highly in our fatal crash statistics.
"Driving under the influence of drugs and being impaired is a high-risk behaviour and a serious road safety concern."
Police had been trained in the legislation, in recognising the effects of drugs, in establishing good cause to suspect someone was impaired, and then administering the CIT test, he said.
If a person failed to complete the test satisfactorily and, in the opinion of the testing officer, was impaired, a blood test was obtained to screen for drugs.
Snr Sgt Larking said the standard initial tests were for cannabis and amphetamines but screening was available for a wide range of drugs.
Cannabis was the drug most commonly detected in the Southern region, he said.
