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Drugged driving related news from around the world:
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Cannabis Poses Less On-Road Risk Than Alcohol, U.S. Crash Data Says
February 22, 2007 - Thunder Bay, Ontario
Published in: Canadian Journal of Public Health

U.S. drivers involved in fatal crashes who had trace levels of cannabis in their blood or urine are less likely to have engaged in risky driving behavior than drivers who test positive for low levels of alcohol, according to case-control data published in the current issue of the Canadian Journal of Public Health.

Over the ten-year period, 1,647 drivers tested negative for alcohol, but tested positive for the presence of THC in their blood or urine.

Researchers concluded that alcohol-free drivers who tested positive for cannabis had a slightly elevated risk of engaging in a potentially unsafe action compared to sober drivers, even after controlling for age, sex, and prior driving record. However, investigators also reported that drivers who tested positive for low levels of alcohol (.05 BAC) possessed a significantly greater risk of engaging in such risky driving behaviors compared to sober drivers.

Investigators wrote: "The findings point to cannabis as a potential risk factor in fatal crashes. Individuals who tested positive for cannabis but negative for alcohol had a 29 percent excess risk of having driven in a fashion that may have contributed to the crash, compared to drivers who tested negative for cannabis. ... Yet these estimates appear small compared to alcohol and some prescription medications."

Canadian researchers also determined that motorists who tested positive for cannabis were generally younger, male, and had a poorer driving record in the prior three years than drivers who tested negative for pot.

THC blood levels typically fall below 5 ng/ml in recreational (non-chronic) cannabis users within 60 to 120 minutes after inhalation.

Oct 3, 2007
New Zealand

VIDEO LINK (11:32):

On the same day the Government tabled new legislation to help police test motorists they suspect are driving while under the influence of drugs, Close Up joined some volunteer drug testers uncovering some alarming results in Lower Hutt. Police Minister Annette King today tabled the Land Transport Amendment Bill which will make it compulsory for drivers police suspect are on drugs to perform a roadside impairment test. A two year study into the emerging problem has revealed that 2-3 motorists a week are killed on New Zealand roads while drugs are present in their blood streams, and that New Zealand has a higher rate of people driving on drugs than than many other countries. Police Minister Annette King was in the Close Up studio to discuss the problem and the new legislation.

Note: "Minister of Police" Annette King, who tabled DUID legislation, said that people who pass the roadside impairment test might still be required to do further tests. She also mentions the use of "booze busts" (RIDE stops) for catching drug impaired drivers.

MAPinc "Drugged-Driving" articles, 2000-2008:

New Zealand
: New Booze Buses To Test Drugged Drivers
29 Feb 2008

Police will now be able to test drivers for drugs as well as alcohol with two state-of-the-art $236,000 "booze buses" delivered to them today. For the first time in New Zealand, police would also be able to use a booze bus to test and process drugged drivers, she said.

"We have been using booze buses in our fight against drink driving for a number of years," she said.

"But the new vehicles take this to a whole new level."


New Zealand: Stoned Drivers 'Bigger Risk'
17 Oct 2007

New research showing stoned drivers are more than 2.5 times more common - and more dangerous - than drunk drivers reinforces moves to introduce drug-driving regulations.

In the latest paper from a long-running Christchurch Health and Development study, a group of 936 drivers aged under 25 were asked how often they had driven under the influence of alcohol or cannabis.

Lead researcher Professor David Fergusson said the team was "quite surprised" by the results, which showed "dopey driving" was more common than drink-driving.

Those questioned reported driving under the influence of cannabis on an average of nine occasions between the ages of 21 and 25.

The average rate for drink-driving was 3.62 times.

Figures from a police and Environmental Science and Research Institute study found that of 408 drivers who died in road accidents in 2005 and 2006, 124 had cannabis in their system, some of whom had also consumed alcohol.

Sixty drivers had consumed alcohol alone, and 50 also tested positive for drugs such as morphine, methadone, methamphetamine and benzodiazapines.


New Zealand: Cannabis Drivers' Drug of Choice
11 Oct 2007

Professor Fergusson said the net effects were that for the group of young people studied, cannabis posed a greater risk than drink-driving.

He pointed out, however, that the accidents were relatively minor and for the most part did not involve injury, and as cannabis use was highest among young adults, the results of the study may only be specific to that age group.


New Zealand: Drug-Driving Saliva Tests May Not Be Accurate
11 Oct 2007

In response to the new figures on the scope of drug driving, ESR scientists have launched a study into how effective a saliva cannabis test is in detecting recently consumed drugs.

It is hoped police will in future be able to use the saliva tests to accurately detect whether someone is still under the influence of cannabis while behind the wheel.Almost 1000 25-year-olds took part in the Otago University research and were asked how many times in the last four years had they driven either dangerously drunk or soon after smoking marijuana.

Participants said they had driven while under the influence of cannabis an average of nine times in four years, compared to about three times while drunk.

Critics of the legislation argue blood tests detect cannabis in a person's system long after they have smoked it. The scientist in charge of an ESR and police project to measure the numbers of dead drivers who had taken drugs disputed the claim.

ESR forensic toxicologist Helen Poulsen said blood tests picked up the presence of cannabis in a person's system from between four hours and 24 hours after they had smoked it.

There were currently some issues with the accuracy of saliva tests, Poulsen said.


New Zealand: Doctor Sceptical On Impact of Proposed New Drugged-Driving Rules
04 Oct 2007

But Shameem Safih, clinical director of Waikato Hospital's emergency department, expected the new legislation to have minimal impact on workload.

"It is not common, alcohol is the far bigger problem for us," he said. "There are isolated cases, but even then it is hard to separate the mixture of drugs and alcohol."

Superintendent Dave Cliff, national manager for road policing, said the new regime would allow the gathering of data to allow authorities to determine the extent of New Zealand's drug-driving problem.

He said police estimated they would prosecute 400 cases a year, compared with 29,000 drink-driving prosecutions.

Transport officials yesterday said it was difficult to determine the impact of drugs on New Zealand's road toll, but they were believed to be responsible for 38 serious injuries, 77 minor injuries and 12 deaths in 2006.

Cannabis law reform group Norml said the bill would result in people who were no danger on the road being prosecuted because the tests would pick up the use of cannabis for up to three months after it was inhaled.


New Zealand: Drugged Driving Bill Introduced To Parliament
03 Oct 2007

People who abused or misused prescription drugs would also face prosecution, though it would be an allowable defence if the drugs were being used as directed by a doctor.

Police expected the new law there would be around 400 prosecutions a year at an estimated total cost of $640,000. There are about 29,000 prosecutions a year for drunk driving.

Police believed that most drugged drivers would be picked up when stopped at "booze bus" roadside checks or when spotted driving erratically.

It was estimated that in 2006 there were 12 road deaths attributable to drugs.


New Zealand: Roadblock for Stoned Driver Law
24 Sep 2007

One police study of 245 dead drivers found that 129 had drugs in their system. Of those, 80 had drugs and alcohol in their systems, 29 had cannabis only and 20had prescription drugs.

Green MP Metiria Turei said if the aim of the bill was to get unsafe drivers off the road "then the reason why they are incapable of driving safely is largely irrelevant".

Police already had considerable powers under the Misuse of Drugs Act: "All this would mean is that it's much, much easier for police to subvert ( those ) powers."

Police Association president Greg O'Connor said drugs were an "aggravating" factor in many road accidents. Frontline police needed better powers to curb drugged drivers.

"People cannot be driving around influenced by all sorts of substances and do so with impunity," Mr O'Connor said.


New Zealand: Drivers On Drugs Face Being Asked To Walk A Straight Line
20 Jul 2007

National road policing manager Superintendent Dave Cliff welcomed the proposed law, saying under the present law it was only illegal to drive while "incapable" because of drugs or alcohol.The new, separate offence for drugs, as with alcohol, would have a lower threshold, requiring a driver to be "impaired". "It's another tool for us to get people who shouldn't be on the road off the road." People suspected of being on drugs will be tested on the side of the road by an "impairment" test, in which people are asked to do co-ordination exercises such as walk in a straight line and undergo eye examinations.

If police believed they were on drugs, a blood test would be done to confirm it. Similar punishments would apply as for speeding drivers.

The Green Party has opposed the measure, saying requiring someone to do a blood test based on an officer's perception of whether they were "impaired" was effectively a search.


New Zealand: Drug Tests For Drivers Set For New Year
19 Dec 2006

Northland police and road safety officials say that with the number of drug-affected drivers on the increase, the new test is a positive move.

"Without a doubt there are some drivers out there taking drugs. At the end of the day they are just as dangerous as the drunk driver," Mr Ward said.

Given the high number of people convicted of cannabis offences in Northland it stood to reason there would be a high number of people driving under the influence of drugs and the statistics back him up.

The last in-depth study done into the number of motorists killed in Northland road crashes showed a high number had smoked cannabis. It revealed 39.3 percent of dead Northland drivers had cannabis in their blood, almost double the 21.1 percent national figure.

Police National Headquarters Superintendent Dave Cliff said the impairment test had a lower threshold than the existing test, which measured whether a driver was "incapable of proper control". The roadside drug test is not compulsory under present law.

Ministry of Transport figures showed drugs were suspected in 36 crashes last year. Drugs were proven in three crashes. There were 383 crashes where alcohol was suspected.

Transport Minister Annette King said it was difficult to pinpoint the level of illegal drug use in drivers "because we do not routinely test for drugs". But she said illegal drug use among drivers, particularly young drivers, was higher than the statistics suggested.

Whangarei lawyer Dave Sayes said that under the Transport Act police were already able to charge drivers under the influence of alcohol and drugs. "The power already exists but the police really haven't utilised it. This is a duplication - end of story."

[*article includes a description of the roadside test.]

New Zealand: Road Safety Policy Statement Launched
NZ Ministry of Transport
13 Dec 2006
Questions and answers on drugged-driving:

Why does the new offence apply only to illegal drugs?

Illegal drugs may be a bigger safety risk than legal drugs. Prescribed medicines and over the counter medicines generally come with substantial warnings where necessary, and are used responsibly by the majority of the population. While the proposed new offence will only apply to illegal drugs the offence of driving while being incapable of proper control will apply to both legal and illegal substances.

What about benzodiazepines (tranquillisers)?

These medicines usually come with warnings about using heavy machinery and driving, and are prescribed by doctors who will ensure their patients are aware of the likely effects. We expect New Zealanders to continue to use prescription medicines responsibly and carefully consider their fitness to drive. Nevertheless where Police detect impairment at the roadside, they will be able to take action to address the immediate risk to road safety by taking the keys from the driver.

Why aren't we doing what the Australians are doing? Why don't we have random testing for illegal drugs?

South Australia, Tasmania and Victoria have introduced random testing for illegal drugs. In these states it is an offence to be driving with detectable levels of certain illegal drugs in your body fluids. In New Zealand, we think it is important to make a link with our road safety goals. What matters is that we identify if the driver is impaired. If we find the driver is impaired by alcohol at a certain level, that is an offence. If we find the driver is impaired by illegal drugs, that will be an offence. Our goal, in line with the harm minimisation principles of the NZ Drug Policy, is to improve the road safety risk.

What will happen at the side of the road?

First, if a police officer suspects a driver is impaired, the usual alcohol detection process will take place. If the driver is not impaired by alcohol, but the police officer is still suspicious of impairment, a roadside impairment test will now be compulsory. The specific impairment test to be undertaken will be published in the NZ Gazette. At the moment, the test, which is not compulsory, includes an eye examination, a balance test, a walk and turn test and other similar tasks. If the driver does not perform these tasks to a satisfactory standard, the police officer will be able to forbid the driver to drive for a period of time (say 24 hours). A blood test will be required, and the driver will then be taken to a police station or medical centre for this. If the driver performs the tests satisfactorily, he or she will be free to go.

Is the test the same for everyone?

The test is the same for everyone, but in judging whether the test has been performed satisfactorily, the Police Officer will make allowances for age, state of health and so on.

What if I fail the test because I am sick?

It may be that the Police Officer refers the case to the Director of Land Transport for consideration of the driver's medical fitness to drive.

Can police stop me anytime, anywhere?

Yes. The test will be compulsory when the Police Officer has reason to suspect impairment.

What about the methadone users (they've killed people in the past)? What about party pills?

The definition of an 'illegal' drug in this road safety context will be very carefully considered as the legislation is drafted. Methadone is a prescription medicine and if it is used in accordance with the prescription, it will not be strictly or specifically illegal to drive while impaired by methadone, or by party pills.

It will still be an offence to be incapable of proper control of a vehicle. The immediate risk of someone driving while impaired will be addressed by taking the keys off the driver at the roadside, whatever substance has impaired them.

What about existing offence for 'improper control'?

The existing offence, for being "under the influence of drink or a drug or both, to such an extent as to be incapable of proper control" of a motor vehicle, will remain unchanged.

New Zealand: NORML New Zealand advisory
Driver Drug-Testing trial begins
10 May 2004


UK: Drug Risk For Party Drivers
19 Dec 2006

While many are aware of the dangers of drink driving, campaigners say drug driving is just as dangerous and carries the same penalties.

Their call comes as a survey found a worrying one third of young people in the North West said they know someone who takes illegal drugs and drives regularly.

According to research, by breakdown organisation Green Flag, 37 per cent of North West passengers had been driven by a driver under the influence of drugs and one in five would drive three hours after taking tranquillisers or anti-depressants, which can affect driving for hours.

For more information on how drugs can impair driving, visit

Any person who knows of any drink or drugged driver can inform police for immediate action, or call Crimestoppers anonymously.

[*Noteworthy: cannabis was not mentioned in this article.]


Australia: The role of drugs in road safety
April 2008


Cannabis (marijuana) is the second most common drug (found in about 15% of fatalities in Victoria), followed by the amphetamine-type stimulants (4%) and opioids (4%). Illicit drugs are present in almost 20% of drivers killed in Victoria.2 A survey of almost 500 injured drivers admitted to a major road trauma hospital found that cannabis products were present in 46%, opioid analgesics in 11% and amphetamines in 4%.


Australia: Police catch 77 drug drivers in random tests
06 March 2008

Seventy-seven Queensland drivers have tested positive in random roadside drug tests - including two drivers who have been detected twice - since they were introduced on December 1 last year.

Police Minister Judy Spence today announced 5800 tests had been conducted across the state, with one in 75 drivers testing positive.

"Random roadside drug testing is taking dangerous, drugged-up drivers off our roads," Ms Spence said.

"Drivers testing positive show the presence of illicit drugs speed, ice, ecstasy or cannabis in their systems.

"These penalties serve as a strong warning to all drivers - we take a zero-tolerance approach to driving under the influence of illicit drugs.


Australia: Drugs Put Swerve On Driving Skills
31 Dec 2007

Marijuana smokers are slow on the road.

While the detrimental effects of alcohol on driving are well documented, scientists are still learning what impact various illegal drugs have on driving skills.

Newtown resident Camilla said she was one of the 5600 people who had been pulled over and checked for illegal substances in the past 12 months.


Australia targets drugged drivers (Ecstasy)
2 September 2006

Police in the Australian state of Victoria have begun randomly testing drivers for the drug ecstasy

The force says it has developed ground-breaking technology to detect the presence of the drug in drivers' saliva and blood.

Last year more than 40 percent of drivers killed on Victoria's roads had traces of drugs other than alcohol.

Australia: First "Drugged Driver" to Sue Police for Defamation
03 June 05

In December, a motorist from the Australian state of Victoria became the first person to be identified as a "drugged driver" under the state's brand-new roadside drug test program. As TV camera crews filmed it all, John de Jong, 40, was pulled over, forced to submit to drug tests, and then accused of testing positive for methamphetamines and marijuana. Only one problem: The roadside tests were wrong, and a police laboratory later cleared de Jong of any wrongdoing.

Now de Jong is suing the government of Victoria for defamation. While the professional courier told the Advertiser newspaper Tuesday that he mainly wants an apology from Victoria police, he is also seeking unspecified damages for harm to his reputation after being falsely identified as a doped-up driver. Police told him his face would not be shown on TV by media they had invited to witness the new policy in action, but it was anyway.

The program, which is still underway, allows police to stop passing motorists at random and force them to submit to a saliva test for cannabis and methamphetamines. Those found to have drugs in their systems are punished by fines similar to those for drunk driving. But unlike Australia's drunk driving laws, which specify a blood alcohol level beyond which impairment is assumed, the drugged driving laws punish drivers for any detectable amount of the drugs, regardless of whether that amount is linked to actual impairment.

Police plan to randomly test some 9,000 drivers this year, they said when the plan was announced in December. Among the targeted locations are areas with heavy truck traffic and "areas known for rave parties," police said.


Australia: Newsbrief: World's First Random Drug Test of Drivers Results in World's First Random Drugged Driver Bust and Threat of World's First Lawsuit Against the Practice

17 Dec 04

The world's first program to randomly drug test drivers got underway in the Australian state of Victoria

Monday, and it scored its first victim within 15 minutes, according to Australian press reports. Under the experimental program, police can stop motorists at will and force them to submit to a saliva test for cannabis and methamphetamines. Those found with the drugs in their systems will be fined in a scheme parallel to drunk driving punishments. But unlike drunk driving laws, which set a limit above which the driver is presumed to be impaired, the drugged driving campaign punishes drivers for having any amount of the drugs in question in their systems, whether or not impairment is proven.

The fourth driver tested in metropolitan Melbourne, 39-year-old John De Jong, tested positive for both methamphetamines and marijuana and was cited. A positive test result is forwarded to a laboratory for confirmation. If the lab confirms the positive result, De Jong will be fined $228.

De Jong, who claimed he had not smoked pot for more than a month, was not happy, and neither was his attorney. "My client's rights have clearly been violated," said Solicitor Katalin Blond. "He's arrived home from work to find his children and family in tears, having seen his face plastered across the television," she told ABC Radio. De Jong is considering bringing lawsuits for defamation and breach of privacy, she added.

Of 32 drivers randomly tested Monday, De Jong was the only one to return a positive result, Victoria police said. But there will be more. Police said they plan to test 9,000 drivers in the state during the next year. They will target trucking corridors and "areas known for rave parties," a police spokesman told the publication The Age.

New Zealand Cannabis Stats (2001)
  • Marijuana is the third most popular recreational drug in New Zealand after alcohol and tobacco (excluding caffeine).
  • In the 1998 National Drugs Survey, 43 percent of males and 27 percent of females aged 18 to 24 years had used marijuana in the preceding 12 months
  • . Most of those who stated that they had tried marijuana had been introduced to the drug at between 14 and 18 years of age.
  • About 70 percent of prosecutions (18,720 prosecutions) for offences involving cannabis resulted in a conviction (13,120 convictions) in 1998. Approximately 85 percent of convictions for cannabis offences each year are of males
  • In 1998 the largest number of convictions were for those between 30 and 39 years old (30 percent of all convicted cases). The age group with the second highest proportion was those aged 20 to 24 years, with 24 percent of all convicted cases.
  • There were seven deaths over the period 1990-96 where a cannabis-related condition such as drug abuse or dependence was the underlying cause of death
  • There were 2722 cannabis-related hospitalisations over the period from 1996 to 1998. There were 4.5 publicly funded hospitalisations per 100,000 population in 1998 where a diagnosis of a cannabis-related condition or poisoning was recorded.

Also see: Drug and Driving: A Compendium of Research Studies

RE: New Zealand

"Researchers suggest that increased accident risk among cannabis users may be more related to the characteristics of the driver rather than the effects of cannabis on the driver behaviour"

Pot’s Effects On Driving Performance Contrast Alcohol’s, Study Says

May 15, 2008 - Jerusalem, Israel


"The present study reveals that although some similarities in the degree of impairment could be observed – mainly with the lower level of THC and alcohol, where both increased reaction time and [lane position variability] – some discrepancies also appeared between the two drugs," authors concluded. "In particular, subjects seemed to be aware of their impairment after THC intake and tried to compensate by driving slower; alcohol seemed to make them overly confident and caused them to drive faster than in control sessions."

MADD Canada: Estimate of DUID prevalence


"As noted above, it has been estimated that about 10% of fatal crashes involve impairment by drugs (licit and illicit) alone. Assuming that the drugs-plus-alcohol frequencies are a sub-set of the instances where alcohol has been found, the estimations overall impairment can be drawn by multiplying the cells in Table 3 by 1.1"

More on MADD : Crash Course On MADD

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