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Road Victim Rights

Land Transport Act - seeking safer laws

MORE ABOUT POT DRIVING

WEED KILLS - POLICE STUDY STATISTICS (IN LIGHT OF INTERNATIONAL CULPABILITY STUDIES) SHOW...

THAT AFTER ALCOHOL IT IS THE NUMBER 1 KILLER DRUG ON NZ ROADS...  IT DOESN'T LAG FAR BEHIND.

POT  PLUS...  POT  PLENTY...  POT JUST LATELY  &  POT JUNIOR DRIVER  ARE  WHERE  THE  BIG  RISKS  LIE.

EARLIER STUDIES FINDING NO POT DRIVING ISSUE DUE TO "COMPENSATORY CAUTION" ARE THOROUGHLY DEBUNKED AS THEY MISTAKENLY LOOKED AT THC-CARBOXY

- A few pot driving deaths here lately were due to unwise overtakes and several studies are coming in co-relating pot driving to speed.

• Cannabis impairs driving ability. Though obvious effects aren't as severe as alcohol's they're complex and highly dangerous due to it's sedative and stimulant properties.

• Studies consistently show much higher crash odds and culpability ratings for cannabis users than sobre drivers, and greater danger than from driving on P (Drummer 2004).

•  Users are being targeted by Road Police everywhere today because of increased use (UNODC) & often strength, greater traffic volumes (personal vehicle use) with concomitant increased exposure to road risk. 

• NZ Government reports indicate Maori economies of Northland and the East Coast are dependent upon growing. Studies accordingly show extremely high use in Maori communities amongst most age groups which has been a public Health concern, along with doubled road tolls per capita of others. 

• Cannabis use at dangerous levels (over 10ng in blood) is now present in slightly more crash deaths than alcohol over limits

• Major household surveys indicate while most smokers are responsible about 8 000 Kiwi users regularly drive stoned. Young male smokers or those mixing use with alcohol have the greatest crash risk per a small Waikato Hospital study - quite consistent with overseas findings.

• The Illicit Drug Monitoring System survey of 2005 found 15-17 year olds are more likely to purchase marijuana from tinny houses than from known trusted sources. This lays young users open to buying potentially laced product with even worse than  ill effects on driving than may have been anticipated.

• Considering that near 40% of Northlands crash dead are found to have consumed cannabis and that local roading is no life saver for local people experiencing 'a lapse' it's no surprise Northland Cops stressed over a 2006 local Xmas toll total of 27 - 4 more than the 2005 total. This years is another disaster.

• Cannabis crop areas generally buck the National trend of slowly reducing road tolls. And never more than during harvest season it would appear. Time and again multi fatality crashes feature cannabis as a contributing factor - often atop fatigue, a hang over or a hard long days work.

Some tolerance could save lives

In the interests of road safety Candor would like Cabinet to consider following Canada's example, of reducing penalties for possession of under 15gms of dope when it's found in the car of an unimpaired driver. To administrative fines of say $150 for adults / $100 for under 18 year olds. Better in the car than in the driver!

The most acute impairment related to intoxication occurs in the first 60 minutes after use. In the next 90 minutes impairment subsides quite rapidly. The degree of impairment during the residual phase depends on the dose of THC consumed. After a typical dose of 20ng the residual phase should last 2-3 hours. 

The 14% of Kiwi users who prefer the stronger weed called 'skunk' (which some countries want listed as class A) or who use hash or resin (Class B in NZ) will naturally be impaired for longer than users of basic weed they should note. 

And if users believe that tolerance is any protection, it is something only gained from nearly daily use, and recent studies indicate that it does not reduce crash risk any and may even increase it.  

 Blurred vision and far sightedness occur for tokers

What are the exact effects on driving?

• Drivers under the influence of a reasonable amount of cannabis, or who have used even a little of some other risk drugs eg alcohol atop a little pot have a harder time steering straight and staying in their lane. 
  
• The Drug Driving Research Unit, Swinburne University (Vic) found while researching various drug effects upon 36 variables of  driving performance that cannabis consumption significantly increases vehicle lane weaving
  
• And that use slows reaction time in 'emergencies'. Researchers concluded cannabis slows information processing so users are slow adjusting to changing driving scenarios.
  
• With any alcohol crash risk is phenomenally increased (Ramaekers lately. Chesher '86, Henderson 94). John Bailey long past identified the problem of cannabis plus alcohol causing major trauma on NZ roads. 
  
• 300mcg/kg of THC which is an average joint or less of strong stuff used solely is as impairing as being at 0.5 blood alcohol. Addition of a depressant drug to cannabis eg a little alcohol greatly ups risk of never going home
  
• A 2003 French study of over 10 000 crash deceased by Jean Martin (Universite Claude Bernard) found users had 16x normal crash risk, and that they were more vulnerable to effects of the crash so more likely to die. Perhaps because users favored motorcycles or did not buckle up or else drowsiness prevented braking.
  
• Driving on sedating cultivars or when fatigued on pot can cause more than "weaving" - falling asleep at the wheel causes a flop forward and a sharp tug on the steering wheel - perhaps pulling you into oncoming lane.
  
• As time sense and depth vision are affected stoned drivers have reduced ability to judge distances and changes in the speed of other vehicles on the road. And to make adjustments to their own speed in time.
  
• Because dope disturbs concentration, attention and short term memory drivers can fail to notice important events and situations  on the road (eg car ahead's brake lights). Slowed and non goal directed thought processes also affect ability to respond to unexpected hazards on time and even correctly
  
• Cannabis users interviewed in Canadian focus groups noted they felt it may be just as risky to drive during the 'burnout' phase sometimes following intoxication. It is something like a hangover and characterised by fatigue. Fatigue is a common cause of severe crashes as these can happen in a split second micro-sleep.
  
• A few studies have now shown that 'to the extent drivers compensate for the effects of cannabis through extra effort into focusing, they appear to be able to manage routine and low demand tasks. But the remaining brainpower seems insufficient to cope with peak and unexpected demands'. (Smiley - 1999, Marijuana)
  
• Cannabis lab studies showing delta 9 thc substantially impairs attention, concentration, hand / eye co-ordination, tracking and reaction times include Couper and Logan 2004, Gieringer 1988, Maskowitz 1985
  
• Some issues found by NIDA studies were impaired retention, vigilance and divided attention task ability. Along with poor problem solving due to uncompleted thought processes. Subjects can pull selves together to concentrate on simple familiar tasks but only for a few minutes. Difficulty sustaining and shifting attention was also found during Blows study.

Drummers 1995 study (and similar of the era) that reassured about cannabis safety was wrongly reassuring as the fact carboxy thc was measured (metabolite present for weeks) meant the sample was biased toward unimpaired pot smokers. Other reassuring older cannabis studies were also flawed as they were based on urine which shows historic use. Using such samples clearly slanted such studies towards finding less risk - just as studying drivers who drank a few days earlier would. 

Drummer revisits the issue in 2004. Using a better methodology he studied 3398 deceased people. And finds an OR (crash risk) of 6.6 (approaches alcohol limit) for drivers over 5ng blood thc. A level of 5ng can't be reached without recent use within 2-3 hours. Reviews of many studies find agreement that only high doses of active delta 9 thc (over 5-7ng) or cannabis with other drugs, including any alcohol, cause problems on road. When use is high or other drugs are in mix culpability is 90% in crashes. 

Longo in 2000 found no heightened risk of injury crashes with marijuana. Like alcohol she found higher risk existed instead for more extreme ie fatal rather than mere injury crashes. Likely due to the crash type often being drowsy related. No brakes or late braking is associated with serious outcomes so a study of cannabis crashes for braking is needed. 

Auckland University Study by Blows et al suggested it is habitual not casual or even recent pot use that ups crash risk of smokers by nearly 10x in NZ. Candor thinks its unusual finding that it is not recent use that's the issue are wishy washy. As they say any raised risk detected after recent use was discounted by taking into account fatigue and non seatbelt use. 

Candor note use may still be what increased the crash risk due to it's increasing the impact of fatigue while under the influence (or causing fatigue in 'burn out') and by intoxicant effects causing or contributing to carelessness. 

Studies (Jesso et al) have shown drug drivers tend to worse driving regardless due to a typically greater risk taking type personality (quite aside from intoxicant effects compounding the problem in some cases). This is also the case with drinkers but the fact can not undermine the importance of drink itself increasing risk. As a dose dependency to ever heightening risk is demonstrable. 

This was also shown lately to be the case with cannabis in several experimental studies. Which made clear impaired cognition and psycho-motor functioning (co-ordination) are THC dose related. And that detrimental effects are more prominent in some driving tasks than others. Highly automated behaviours like road tracking are more affected than complex driving tasks requiring conscious conscious 

On road studies are today cementing evidence as different variables affect risk in reality than lab studies can account for. Earlier on road studies were difficult due to methodological issues like needing fast blood tests. But the fact saliva tests now co-relate very well to active blood drug cannabis levels (only high soon after use), and are only 1% inaccurate has made important studies lately possible. 

On road studies show active cannabis is present in anything from 2% of injured drivers to 32% (Italy) depending where you look – Kelly et al '04. NZ likely takes the cake in whole world with ESR study results 2006 showing 47% of dead drivers used weed up from 22% a decade ago. The sample may be a little skewed due to collection in green areas.

Impairment on driving simulators lasts up to 3 hours. Shinar et al in 2004 found smokers had decreased driving speed (doesn't equate to safer driving ),  but also poor vehicle control and they again related this to attention problems as evidenced by correlating variability in heart rates.  

Ramaekers view is that 7-10ng is the thresh-hold separating lower risk pot drivers from menaces. Though some US states have set limits at 2mg. Europe has tended to go for 5ng.