Getting behind the wheel after smoking cannabis will almost double your chance of having a serious or fatal crash, new research has shown.
This comes as more and more Kiwis are being caught drug driving following the introduction of roadside drug tests at the end of 2009.
Figures released to Fairfax Media recently showed since then, 514 people had appeared to be sufficiently impaired for police to perform a drug test – and 455 drivers were found to be under the influence of drugs.
More than half were under the influence of cannabis, with methamphetamine or BZP the next most common drugs.
Canadian research published recently in the British Medical Journal reviewed previous studies on the subject and found acute cannabis consumption could be linked to an increase in crash rates, particularly fatal crashes.
The research found cannabis significantly impaired the psychomotor response, or muscle activity linked to mental processes.
The impact of acute cannabis consumption on the risk of minor crashes remains unclear.
A report from New Zealand police showed 48% of deceased drivers tested positive for the presence of alcohol or drugs.
In the report, Dr Helen Poulsen of Environmental Science and Research Ltd found of the drivers who tested positive, 19% recorded the presence of cannabis, 27% of alcohol, and 28% of both alcohol and cannabis. Most of the 455 caught driving while under the influence of drugs were disqualified from driving and given a fine or community work. Six were given home detention and 15 received jail sentences.
The Land Transport Amendment Act 2009 will be reviewed this year and police are investigating the possibility of introducing more effective roadside drug tests.
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