Roadside dope testing?

One of Professor Bunyip’s blogging obsessions is excessively intrusive traffic policing in his home State of Victoria. It’s understandable if Bracks’ henchmen are anything like NSW, with whose practices I’m much more familiar through annual holiday visits. Speed cameras proliferate, usually positioned at locations having little or nothing to do with safety and everything to do with maximising revenue.

As far as I can see, the Professor’s position (like mine) flows from a liberal philosophical position rather than narrow self-interest. Then again, I should confess that I’ve been zapped a couple of times in the last 4 years by speed cameras in Darwin, and twice in one week a couple of years ago going down Spit Hill in Sydney (apparently the highest revenue-raising speed camera in Australia – no doubt because it’s impossible to keep below the speed limit without shifting down gears or keeping your foot on the brake).

The Professor has emailed me querying my attitude towards random saliva testing of drivers for cannabis and other drugs. Apparently it was recently introduced in Victoria, and is already snaring lots of victims:

Victoria Australia police’s operation to randomly test drivers for traces of drugs had a dramatic start, with two motorists out of the first 16 tested returning positive samples.

Police say that within minutes of starting the tests in Yarraville, two motorists tested positive to traces of cannabis.

If secondary samples also prove positive, those drivers face fines of $300 and license demerit points.

Assistant Commissioner Bob Hastings says officers had no idea the initial tests would produce results so soon.

“We had a driver test positive within our fourth driver into the queue and that was somewhat surprising so early on,” he said.

“As I said, we had no real expectation of what we were going to find out on the roads but it was a surprise.”

The Professor first asks about the constitutional situation in the US where, he observes:

police in the US can’t pull people over at random, since this has been ruled a violation of the bit in the Constitution dealing with unjust and discriminatory search and seizure. If American coppers want to run sobriety tests, they must test all drivers who come down the road, not just those that tickle Cadet Constable Plod’s particular interest.

The Professor is essentially correct, as this Findlaw article explains. Under the Fourth Amendment to the US Constitution, police need “probable cause” to administer something like a breath or saliva test. They can’t simply do it at random as occurs in Australia. But I’m not sure it makes any real practical difference. Ther would be no constitutional bar to American police pulling over motorists as long as they did it in a systematic rather than random way. But having pulled them over, they couldn’t subject a motorist to breath or saliva testing unless they had “probable cause”. But that would simply mean smelling alcohol on the breath or noticing bloodshot eyes or something of that sort. And once you tested positive, you could guarantee the officer would swear blind that he had smelled or noticed it and you’d have no way of proving otherwise.

A more interesting question is whether we should view roadside drug testing in the same way we view alcohol testing. The Professor’s attitude towards the latter mirrors my own:

Don’t imagine that I oppose alcohol testing, as I don’t. There is ample evidence of the harm alcohol does behind the wheel, there are clinical calibrations for degees of inebriation, and the tests themselves take a mere few seconds and involve no great inconvenience. Plus they are reliable, which the saliva tests clearly are not — and booze testing is clearly warranted by the grim statistics of Victoria’s former road toll. You couldn’t have been in Victoria in the late Sixties/Seventies and not been aware of the damage grog was doing to innocents. One Easter, if I remember correctly, something like 34 people died, most of them no doubt pissed or the victims of the pissed.

But the Professor sees cannabis testing as more problematic:

The surveys on driving while stoned show no such clear co-relation. One piece in the New Scientist reported test results that actually showed improved driving performance. And the most comprehensive survey of driving ability, conducted in Holland and the only one of which I’m aware to use real cars and public roadways, found only a minimal decrease in coordination (there was a slight tendency to drift to right or left, but not out of the lane and not dangerously; women, if I remember, drift more than men, but so do they in most things, apart from the enforcing of their will).

That summary certainly appears to reflect the information in this 4 year old BBC Story. But it seems that more recent research is less rosy for the potheads. Not only is there last week’s Four Corners story (not specifically about cannabis’s effects on driving ability), but this 2 year old ABC TV Catalyst story:

Drugs are now responsible for more deaths on the road than alcohol, and the most common is marijuana. So the government in Victoria has pledged to introduce the equivalent of the alcohol breath test. Catalyst’s Graham Phillips investigates Australia’s first random roadside drug test.

Philip Swan is searching for the equivalent of the random breath test. For drugs this is a saliva test, where a driver has a swab put under their tongue. But that’s where the random drug-test dream gets problematic. Swan is currently evaluating the wares of a number of instrument companies from around the world to see if there is any product up to the task.

The other question hanging over random drug testing is: what is the equivalent of .05 for substances like marijuana? How many joints could a person smoke and still be capable in the drivers’ seat?

Researchers at Swinburn University are trying to evaluate this. They get volunteers to smoke joints and drink alcohol and then jump behind the wheel of a driving simulator. The scientists then monitor their vital statistics, like how fast they drive, whether they drift out of the lane and how well they respond to sudden surprises on the road.

So far they have managed to dispel one of the great myths about marijuana. While it is true that marijuana drivers tend to drive more slowly, they are not safer. Their weakness is an inability to make quick decisions when something unusual happens on the road. Work is still in progress to see what the equivalent of .05 would be. …

Narration: The debate’s being going on for years, but at last we have a definitive answer. For more than a decade, everyone who’s ended up in this Melbourne morgue from a car accident has had their blood analysed”¦to see if the crash was caused by alcohol, marijuana, amphetamines or other drugs. And Olaf Drummer’s results were staggering.

Professor Olaf Drummer: Drivers who use cannabis and are driving shortly after are almost seven times higher risk of being involved in a fatal crash than a drug free driver.

Narration: In fact, drugs combined kill more people on the roads now than alcohol, and the leading killer drug is marijuana. This result was a genuine surprise, because some studies had shown marijuana was not that dangerous”¦ because it makes you a more cautious driver.

Dr Katherine Tzambazis: Yes, there were some reports suggesting that those who consumed cannabis actually overestimate the effects of the drugs and therefore compensate for those impairing effects.

Narration: But the manager of drugs alcohol and fatigue for Vic Roads, Philip Swann, says many of the academic studies were fundamentally flawed.

Dr Philip Swann: One of the problems we’ve found is that academics are limited by ethics committees to study very low doses and that bears no resemblance to what happens on the road. The sorts of levels that are found in the morgue are much higher.

That strikes me as pretty persuasive. My approach to these sorts of issues is essentially a classical liberal one. I apply JS Mill’s observation that “[T]he burden of proof is supposed to lie with those who are against liberty; who contend for any restriction or prohibition”¦. The a priori assumption is in favour of freedom”¦” Of course, if I was discussing it with Mark Bahnisch, I’d have to concede that the communitarian critique of liberalism has considerable force, that we’re indisputably social beings and that society is probably ontologically prior to the individual. But that doesn’t negate the force of a classical liberal approach in the political arena. JS Mill’s approach ensures that convinced authoritarians, who arrogantly seek to impose their own opinions and moral intuitions on the rest of us, can only do so after proving that the balance of harm really does strongly favour regulation.

But application of that principle to the research findings outlined above suggests that the burden of proof has been satisfied in relation to the effects of cannabis, provided that it has also now been established what concentration of THC in the bloodstream is equivalent in impairment terms to .05% blood alcohol, and that the test kits police are using can reliably detect those levels and not snare too many false positives.

Update – The Good Professor reckons I’ve “come down on the side of Bracks the Thief“. He needs to read my post more carefully, in particular the last sentence starting with the words “provided that”. It’s manifestly a critically important proviso, as some other commenters recognised. Although (as Yobbo claimed) alcohol has different effects on different people too, the fact remains that the 0.05% blood alcohol limit is well-supported by research, in that both controlled driving tests and road accident data show that that level of alcohol in the blood leads on average to a very large increase in accident risk. Unless research on the driving impairment effects of cannabis has reached a similar point of specificty on a genuinely threshold limit, the current Victorian regime is just a revenue-raising stunt on a par with the actual operation of speed cameras. Is there a threshold limit for conviction for cannabis DUI, or is it zero tolerance? The Victorian government’s Drive Alive site makes no mention of any threshold limit, which rather leads me to suspect it is a zero limit (which would be outrageous and unjustifiable). However, since I have no immediate plans to drive in Victoria anyway, and won’t be doing it stoned even when I do, my outrage is shallow and it’s not a question I’m deeply motivated to explore.

I also simply don’t know (but am idly interested) whether research has reached the point of establishing a credible, non-arbitrary driving threshold impairment limit. The Professor might like to phone those researchers at Swinburn Tech University and ask them. After all, it’s only a local call for him, and they started work on that task 2 years ago according to the story quoted above. You’d reckon they’d have achieved some concrete results by now, unless they’ve been smoking the research materials.

The Professor threatens to post again on this topic in the near future. I’ll be awaiting his findings with interest.

Update 2 – Looks like my suspicion was right. According to this NSW government briefing paper, “The Road Safety (Drug Driving) Act 2003 (Vic) commenced on 1 December 2004, making it an offence to drive a motor vehicle with any concentration of cannabis or methylamphetamine in the blood or oral fluid.” Here’s a link to the Act itself. Indeed section 4 provides:

prescribed concentration of drugs” means, in the case of a prescribed illicit drug, any concentration of the drug present in the blood or oral fluid of that person …

Come to think of it, if Rex Ringschott is correct that THC doesn’t in fact get secreted in saliva but is only picked up in debris in the mouth, there might be the glimmer of a workable defence, in that the concentration can’t be said to be present “in the … oral fluid of that person”. Trouble is, it appears they give you a blood test too once they get the positive saliva sample. THC is so persistent in the bloodstream that they’d almost certainly zap you anyway, unless you were like Jeff Shaw and had a friend in camp who slipped you both blood samples by mistake.

About Ken Parish

Ken Parish is a legal academic, with research areas in public law (constitutional and administrative law), civil procedure and teaching & learning theory and practice. He has been a legal academic for almost 20 years. Before that he ran a legal practice in Darwin for 15 years and was a Member of the NT Legislative Assembly for almost 4 years in the early 1990s.
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Rex
Rex
2022 years ago

The Professor might want to consider this regarding the affect of cannibis and amphetimines on driving ability.

http://www.druginfo.com.au//article.asp?id=7647&ContainerID=648

And also examine the exact procedure undertaken by the Victoria Police

http://www.arrivealive.vic.gov.au/c_drugsAD.html

Which involves a three step process:
1. Initial Saliva Test – A screening test
2. A Second Saliva Test – A confirmation Test
3. The sample is then sent to a laboratory for full analysis. Only if this last test proves positive will the driver be charged.

But this paper here explains that “THC is not
actually secreted into saliva (Thompson & Cone 1987; Hawkes & Chang 1986) but is detected as
debris within the oral cavity. Thus, there will be much variability in detecting THC in oral fluid. Any suggestion of impairment due to cannabis is predicated on residual matter not being removed by drinking fluids or mouthwashing
soon after smoking.

http://www.aic.gov.au/publications/tandi/ti205.pdf

So that supports Bunyip’s thesis that its unreliable. I guess the message here is if you’re going to do it. Then you should wash your mouth out with soap.

adam
2022 years ago

Hi. Pleased to see some intelligent perspective from you on this, as the program – at its essence – is not testing for impairment. Therefore, what is this exercise about? As you say, 0.05 is a proven measure of impairment, whereas many individuals have such a tolerance that they can smoke large amounts of dope before seeing any effect, etc.

The Victorian Government – in its capacity as the paramilitary wing of the Herald-Sun – is sticking by its story, and so now we have a bullshit piece of legislation that they refuse to back down on out of pride; a la the teacher from Orbost.

Cheers!

Jozef Imrich
2022 years ago

“Strategy without tactics is the slowest route to victory. Tactics without strategy is the noise before defeat.”
-Sun Tzu: Complements of Dana VanDen Heuvel

From Learning Curves to Learning Curbs:

If the purpose of the police drug testing exercise is to reduce car fatalities that is very commendable, but if it a sneaky way of police management to introduce a user pay principle or some kind of return on investment methodology – fund your own police force – then we are in trouble…

Lets hope a regular defensive driving becomes a must for young and drivers who are over 50 ;-D! (Insurance company could sponsor some of the defensive driving initiative – actuaries agree that it would be cheaper to pay drivers over 50 to stay at home and blog or some other ways to keep them off the roads)

It would also help if P platers were not allowed to carry passengers other than their parents or siblings. Peer pressure can push even sensible teenager to accelarate on dangerous curbs.

Police could invest in helicopters or the emerging tagging web-based technology to trace offenders rather than pursuing them along narrow streets …

BTW, It appears that more often than not, it’s simply a matter of choosing the right kinds of drugs … Ecstasy and alcohol disappear from our system within hours; However, if the Professor likes to inhale marijuana – it can take up to 30 days ;-P

Q & A on Drug Testing

Jozef Imrich
2022 years ago
Ken Parish
Ken Parish
2022 years ago

Jozef

Given your caustic comment, I should record that the Professor was careful to disclaim any self-interested motive in challenging the desirability of roadside cannabis testing. Like me, he freely admits to being a bit partial to the demon weed in his young and silly days but, like me as well, he grew out of it some considerable time ago. His concern, like mine, springs from a principled basis.

Jozef Imrich
2022 years ago

Speaking of caustic comments that end with a smile :-P, Ken

Police and Poetry

I saw him parked in the middle of the highway.
I tapped my brakes and slowed down to 65 from 80.
Looked in the rearview, too late he was pulling out,
I pulled over, rolled down the widow, got my license ready.
Poet: “Hello officer, how are you today, saw you slowed down,
Please don’t give me a ticket; I’m on a book tour.
Cop: “What’s your book called?”

yobbo
2022 years ago

“As you say, 0.05 is a proven measure of impairment, whereas many individuals have such a tolerance that they can smoke large amounts of dope before seeing any effect, etc.”

Rubbish. 0.05% BAC is simply a measure of alcohol in the blood. Alcohol affects everyone differently like any other drug – some people will be completely incapable of driving at that limit, and some are not affected at all. Limits in the US range from 0.05% to 0.1%.

It’s exactly the same principle as what you have noted for marijuana. The fact is that blood percentage tests are not an accurate determination of driving ability. The best way to determine whether or not someone is capable of driving is to administer a roadside test measuring reaction and balance – the good old walk-this-line or whatever else they used to use.

Jim Birch
Jim Birch
2022 years ago

…and i’ve got several written off cars to prove it.

Rob
Rob
2022 years ago

I once (many many years ago) drove under the influence of hash. Boy, I wouldn’t want to do it again. I sashayed up to the lights, thinking,’Lovely colour, lovely colour, how cool, how cool’. Realised in time the colour was red. Maybe it was bad hash.

Mark U
Mark U
2022 years ago

“Everyone who’s ended up in this Melbourne morgue from a car accident has had their blood analysed to see if the crash was caused by alcohol, marijuana, amphetamines or other drugs….Drivers who use cannabis and are driving shortly after are almost seven times higher risk of being involved in a fatal crash than a drug free driver.”

I am not saying that marijuana does not impair driving, but I would like to know more about what was done here before accepting Prof Drummer’s analysis as conclusive proof of the degree of danger from marijuana. First, testing the victims blood samples does not tell you that the crash was caused by the drugs. Is there a control group for this experiment and if so what is it? Do they have any idea of the proportions of people driving under the influence of drugs that do not have accidents? Are there other possible factors that could be affecting road deaths? A high proportion of accidents occur at night when, as well as the effects of drugs, drivers are tired and driving conditions are more adverse (especially for young people who are not taught to drive at night).

wbb
wbb
2022 years ago

“Like me, he freely admits to being a bit partial to the demon weed in his young and silly days but, like me as well, he grew out of it some considerable time ago. His concern, like mine, springs from a principled basis.”

???? – there’s some food for thought in that lot!

Jozef Imrich
2022 years ago

Ach Ken,

It is early in Sydney, but I managed to get a baker’s dozen of hot cross buns to go with my strong kofi. I needed it as the blogosphere is proving a minefield. No more caustic jokes from me even if one is tempted to suggest that some of us are a joke of Barry O’Farrell’s proportions ;-)

It appears that my czech mates will no longer treat commentariats as an avenue for soft-core or hard-core discussions:

“Petr Partyk criticized a city bureaucrat on a web discussion forum, and now faces prison over it. What’s more, he says the comments were written by someone else. It looks absurd, but according to a decision by the Prague 7 district court he could be in prison for 75 days for libel.”
Headline reads – Man goes to prison over website comments
http://www.arellanes.com/wordpress/?p=1952

Michael Gill
Michael Gill
2022 years ago

I’d be interested to know why Josef Imrich suggests that citizens over 50 should be regarded as suspect drivers. As a 52 year old driver I must say that my experience with friend, family, colleagues and clients suggests that 70 would be a more realistic age group for testing.

Ken Parish
Ken Parish
2022 years ago

Maybe he was joking about that too. I’m not good at deciphering these emoticon thingsies, partly because many people seem to use them just to soften the edges of a negative comment that really WAS intended in all seriousness. When used in that way, it actually amplifies the impact.

Jozef Imrich
2022 years ago

On a serious note: My Troppoarmadillo Roulette is buried below:

http://troppoarmadillo.ubersportingpundit.com/archives/003042.html

adrian
2022 years ago

As a 51 yo professional driver averaging 1500 City kilometres per week, I’m having no problems nor accidents, thanks very much Jozef. My secret is to eat and sleep properly, use no alcohol or drugs and do some daily exercise. Sweet.

Some years ago, Newcastle Uni conducted and publicised a survey on drivers in vehicle accidents. From memory the results were very interesting regarding who was at fault in these accidents.

A surprising number of accident drivers tested positive for pot. However, an overwhelming percentage of those potters were judged to be in the right !

My guess is that pot drivers have a tendency to not only ‘drift’ in lanes but also ‘surge’ on the power. This causes much frustration for surrounding drivers, who then take radical action, thereby resulting in accidents.

Jozef Imrich
2022 years ago

To use Boris Johnson’s expression, I could not disagree with you less, Adrian.

Believe me, I want to keep on the right side of any Irish taxi driver … no one drives so much traffic to websites as you. God bless the Irish!

Happy Easter ;-D

Jozef Imrich
2022 years ago

To use Boris Johnson’s expression, I could not disagree with you less, Adrian.

Believe me, I want to keep on the right side of any Irish taxi driver … no one drives so much traffic to websites as you. God bless the Irish!

Happy Easter ;-D

Jimbo
Jimbo
2022 years ago

Good comments thread.

I used to work in the road safety business (in fact, at one time I worked for Philip Swann!)

As others have pointed out, the problem with the Vic Police drug test initiative is that it doesn’t demonstrate proof of impairment.

The situation with alcohol is quite different. Contrary to yobbo’s assertion, the relationship between BAC level and accident involvement was clearly established as far back as the 1960s. Interestingly, the first significant data-point in the studies preceding the introduction of random breath testing was actually 0.08; the 0.05 limit was not at the time justified by the data (although there may be better studies today).

The situation with marijuana is much more complicated. Like alcohol, the period of intoxication is relatively short (dependant on dose, but usually a few hours). Unlike alcohol, THC (the active ingredient of cannabis) is not rapidly and predictably secreted from the body. Which means that cannabanoids can be detected in the body days after ingestion. This means that to say that x% of casualties test positive for THC is meaningless

Walter Plinge
Walter Plinge
2022 years ago

This drug testing seems to be rather selective. No testing for opiates, solvents, GHB, ketamine, prescription drugs &c. Having been side-swiped at 1:00am by a women full of prescribed tranx and on the wrong side of the road a few years ago, I’d say legal drugs were just a great a problem. All too hard or impossible – and therefore hypocritical.

The impairment test sounds like the way to go.

Jozef Imrich
2022 years ago

If road safety is at issue here shouldn’t the potholes on roads be also one of the top priorities for the government to address… Providing an affordable and reliable public transport would not also go astray, especially at night. Should insurance companies cross sponsor the services provided by the taxi companies? If drug testing is just another stick to apply in a very selective way the solution might be generating more problems and at what cost … As Walter rightly pointed out impairment test is the way to go. Back to common sense of walking along the white line on the road?

I understand that the (Good) Professor is recommending the commentariat to his readers as the following was written in the spirit of the Green Thursday:

Ken Parish has had a look at the standard sheaf of evidence presented by supporters of the Shakedown State’s Sultans of Spit, accepted the argument that safe roads warrant random saliva tests and come down on the side of Bracks the Thief. He misses the crucial points: the tests are neither reliable, with false positives common, and that even when they register the relatively recent use of marijuana, their findings say nothing of impairment, for which there is no officially recognised standard. It is those facts that tip the scale against any argument on behalf of the “common good” and make the indigity of being obliged to present one’s palate for inspection a violation of individual liberty, not to mention dignity.

French doctors often slip medication through the postern gate. If marijuana could be taken the same way (there would be much less sharing, one guesses), would policemen be authorised to bend you over the mudguard and take an anal swab? Different orifice, same gross principle.

There will be more posts on this subject in coming weeks, including some that could be useful. In the meantime, read Ken’s thoughts and check the commenters’ links. Some are very interesting.
– posted by Stanley @ Thursday, March 24, 2005

Polly
Polly
2022 years ago

My concern with the testing is that they do seem to be inaccurate. How embarassing for the gentleman who was declared the first druggie caught by Vic roadsie testing, to have his face all over the news and then it turns out the test was wrong.

I also have concern about the sniffer dogs. How can the dogs searching you be legal when they don’t have just cause. The dogs don’t appear to be particularly accurate with less than 30% of body searches coming up with anything. I regularly get sniffed by these dogs as I pass through a train station on my way home from work.