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Drug driving blood test

cityboyjim

Got stopped at road block and arrested and drug driving blood tested.I got results back today .Just zero alcohol.No mention of drugs on the form .Do they also test for alcohol as well as drugs and drug results come later, or did I get the incorrect form back.Thanks .

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BaronVon

joeguevara wrote: »

I never did road traffic offence cases but listened to colleagues discuss the mechanics of them. I remember one specific issue of someone smoking or chewing gum or something similar before the breathalyser in the station and it was dismissed as there should be nothing eaten or swallowed. I could have picked it up wrong.

Yeah, the arrested person has to be 'nil by mouth' for 20 minutes prior to obtaining the breath specimen, to ensure there is no excess alcohol in the mouth, which could cause a higher reading. Like everything in drink driving, it was fought to death in the courts, and many cases were dismissed on it, or some other technical breach, but I think most of them have been exhausted by now....:eek:

ohnonotgmail

joeguevara wrote: »

I never did road traffic offence cases but listened to colleagues discuss the mechanics of them. I remember one specific issue of someone smoking or chewing gum or something similar before the breathalyser in the station and it was dismissed as there should be nothing eaten or swallowed. I could have picked it up wrong.

But me being me, I throw different scenarios around in my head to see if they would work. Now I have to preface this as purely academic and not suggesting it. If it is a breach of any rules then Mod have no problem deleting. So I was thinking that the roadside test is only indicative and not admissible as evidence in court. Now heard so many stories about wanting to be spoken to in Irish and want to read the Legislation in Irish as a delay tactic. Not the best. But if a person when arrive in station and before any interaction suddenly collapsed and had to be rushed to hospital where they were unconscious and unresponsive for over 3 hours, then any blood test is past the time period. It would be illegal to take blood without consent. Be a good one for a play, but not in real life.

Peregrinus wrote: »

Refusing to give a sample is itself an offence which attracts a similar penalty to giving a sample and failing. To refuse you don't have to say "I refuse"; just to behave in a way that means a sample can't be taken. So if you were to fake unconsciousness, you'd be guilty of that offence. And if you think you can spend three hours in hospital faking an unconscious collapse and not have the medics aware that you are faking it, think again.

Plus, if you're brought in unresponsive to A&E they'll be taking bloods anyway, for diagnostic purposes. Your consent is presumed in those circumstances. Oh, gosh, look, here's a blood sample that was taken within the 3-hour window; we can test that.

Might be a good one for a play, but it wouldn't be a very realistic play.

the preferred method to test if somebody is unresponsive is to rub your knuckles down their breast bone. If you are faking it you will be found out immediately.

Peregrinus

Refusing to give a sample is itself an offence which attracts a similar penalty to giving a sample and failing. To refuse you don't have to say "I refuse"; just to behave in a way that means a sample can't be taken. So if you were to fake unconsciousness, you'd be guilty of that offence. And if you think you can spend three hours in hospital faking an unconscious collapse and not have the medics aware that you are faking it, think again.

Plus, if you're brought in unresponsive to A&E they'll be taking bloods anyway, for diagnostic purposes. Your consent is presumed in those circumstances. Oh, gosh, look, here's a blood sample that was taken within the 3-hour window; we can test that.

Might be a good one for a play, but it wouldn't be a very realistic play.

joeguevara

BaronVon wrote: »

The Guard makes the legal demand to the arrested person to provide a specimen to the doctor, who is a registered doctor who is designated by the guard to take the specimen. His role is not for the medical purposes of the arrested person. The arrested person can have their own doctor present too at their own expense, if they wish. It is an offence not to comply with the Guard's requirement to provide the specimen, and it carries a 4 year driving ban, if convicted.

The arrested person does not sign a consent form. The doctor completes the form, which is sent with the specimen to the Medical Bureau for Road Safety for analysis.

I never did road traffic offence cases but listened to colleagues discuss the mechanics of them. I remember one specific issue of someone smoking or chewing gum or something similar before the breathalyser in the station and it was dismissed as there should be nothing eaten or swallowed. I could have picked it up wrong.

But me being me, I throw different scenarios around in my head to see if they would work. Now I have to preface this as purely academic and not suggesting it. If it is a breach of any rules then Mod have no problem deleting. So I was thinking that the roadside test is only indicative and not admissible as evidence in court. Now heard so many stories about wanting to be spoken to in Irish and want to read the Legislation in Irish as a delay tactic. Not the best. But if a person when arrive in station and before any interaction suddenly collapsed and had to be rushed to hospital where they were unconscious and unresponsive for over 3 hours, then any blood test is past the time period. It would be illegal to take blood without consent. Be a good one for a play, but not in real life.

Potential-Monke

BaronVon wrote: »

The arrested person does not sign a consent form. The doctor completes the form, which is sent with the specimen to the Medical Bureau for Road Safety for analysis.

Clarified, thank you. I was incorrect. I knew there was a form though! :pac:

BaronVon

Carawaystick wrote: »

So how is the doctor covered?

Lets say a person gets their blood taken, is below the legal limit, and then complains to the medical council stating they did not freely consent to the medical procedure undertaken by the doctor.

Or if there are side effects from the procedure, is the state or the doctor liable?

The Guard makes the legal demand to the arrested person to provide a specimen to the doctor, who is a registered doctor who is designated by the guard to take the specimen. His role is not for the medical purposes of the arrested person. The arrested person can have their own doctor present too at their own expense, if they wish. It is an offence not to comply with the Guard's requirement to provide the specimen, and it carries a 4 year driving ban, if convicted.

The arrested person does not sign a consent form. The doctor completes the form, which is sent with the specimen to the Medical Bureau for Road Safety for analysis.

Potential-Monke

Vestiapx wrote: »

It's the reason I never smoke anymore. I just can't have the Hassel of a conviction for having a joint on a Friday evening and watching Breakfast club and being tested the following Wednesday.

Probably be legalised some day but right now I'll have to go without.

Even if it's legalised, I can't see them changing the current legislation until it's challenged and the legislation is found lacking. I think there's a strong case there, but you'd need the right solicitor, a motivated one who actually wants to win rather than getting paid to win. If one could tie it into a breach of some right, or against some part of the constitution, you'd be onto a winner imo.

Vestiapx

antix80 wrote: »

That would make me think twice about using cannabis. You don't even have to be under the influence of cannabis to end up with a motoring conviction as long as it's in your system.

It's the reason I never smoke anymore. I just can't have the Hassel of a conviction for having a joint on a Friday evening and watching Breakfast club and being tested the following Wednesday.

Probably be legalised some day but right now I'll have to go without.

Potential-Monke

Carawaystick wrote: »

So how is the doctor covered?

the Medical council rules on informed patient consent

Lets say a person gets their blood taken, is below the legal limit, and then complains to the medical council stating they did not freely consent to the medical procedure undertaken by the doctor.

Or if there are side effects from the procedure, is the state or the doctor liable?

IIRC, it's all on the form, the suspect giving the sample signs the form which is read out to them and gives their consent to the doctor to take the sample. It's well covered (can't find an example of the form). You can read the procedure legislation here but I'm not savvy enough to know if there are amendments, which I'm sure there are due to the drug driving legislation now. The legislation just references consent, but doesn't have a copy of the form.

Basically, there's written consent so nothing can be done afterwards. You even get to keep half of the sample if you wish.

Plus you'll have the Garda there taking notes of what happens and what was said, and they'll give evidence as to same if needed. If there was a loophole, it would already have been found, and it's well covered because someone already thought of this at some point, challenged it, won, and the legislation was amended.

Edit: Clarified, there is no form for consent, it's a legal demand of the Gardai which carries a penalty for not complying.

Carawaystick

Potential-Monke wrote: »

By law, you've to provide a sample by signing a form for the doctor. If you refuse, you get charged with a separate offence of failing to provide a sample and it carries the same penalty as if you were charged with being over the limit.

So how is the doctor covered?

the Medical council rules on informed patient consent

Patients undergoing invasive procedures should normally give express consent
– either by signing a consent form or stating that they agree to go ahead with
treatment.
Written consent should always be taken where:
■ There are significant risks or side effects associated with the proposed
treatment or procedure.
■ The patient’s lifestyle, employment or personal relationships could be
adversely affected by the outcome of the treatment or procedure.
■ The treatment or procedure is being undertaken as part of a research
programme.
■ The main purpose of the proposed treatment or procedure is not the patient’s
clinical care.
However, consent is often implied by the patient’s compliance, an obvious
example being when a patient rolls up a sleeve so that a blood sample can be
taken. Nevertheless, patients should be told about the nature and purpose of any
examination, investigation or procedure beforehand.

Lets say a person gets their blood taken, is below the legal limit, and then complains to the medical council stating they did not freely consent to the medical procedure undertaken by the doctor.

Or if there are side effects from the procedure, is the state or the doctor liable?

Potential-Monke

BaronVon wrote: »

You could be convicted of simple possession of cannabis, so being convicted of driving while under the influence of it isn't that much of a stretch of the imagination!

You can only be convicted of simple possession if the product is found on you, wouldn't have any bearing on the test. Having it in your system isn't the same as having the product on your person.

BaronVon wrote: »

https://www.ucd.ie/mbrs/t4media/MBRS%20Roadside%20Drug%20Testing%20Report.pdf

That's exactly what I was looking for, thanks!

BaronVon

Potential-Monke wrote: »

I just find it strange that someone can be prosecuted on the 1ng/ml when there is so much evidence to prove that you can't put a figure on it.

You could be convicted of simple possession of cannabis, so being convicted of driving while under the influence of it isn't that much of a stretch of the imagination!

But to take a quote re Urine samples:

"In regular users, metabolite levels can build up to background levels above 1,000 ng/ml. Many days or weeks of abstinence are required to clear out, as illustrated in the following graph of metabolite levels in test subjects who were regular users"

So blood is definitely the better option at the station, but even then if you're a regular user (daily) or heavy user, you could show above the min level even if you hadn't smoked for a few days with urine.

If you fail a roadside drug test, you are brought back to the station where a doctor takes a blood specimen, there is no option for urine when drugs is suspected. This is because the blood test is much more reliable. The blood/urine option is only for alcohol, but normally a breath test is the preferred option.

If you do provide blood / urine specimen when suspected for alcohol, it will be tested for drugs if no alcohol is found. But the guard would still need evidence of impairment to convict.

The Medical Bureau of Road Safety are the think tank for all of this, and would have made the recommendations to the government on the drug limits. Here is their report on the process.....

https://www.ucd.ie/mbrs/t4media/MBRS%20Roadside%20Drug%20Testing%20Report.pdf

Peregrinus

Chicoso wrote: »

I thought that was the jist of what the Garda was saying

You should pass the roadside drug test after a nights sleep?

If I've understood correctly, unless you're still feeling the effects, you should pass. But "should" is not the same as "definitely will".

Chicoso

Not talking about the blood test now back at the station

Sorry for confusion

Chicoso

Peregrinus wrote: »

It seems to be saying that the Drager unit shouldn't detect THC in oral fluid more than about six hours after last use - unless you are still feeling the effects of it, in which case (I'm guessing) that's a sign that your THC levels have remained high, and are likely to be detectable.

But that's shouldn't detect THC, not definitely won't detect it. There'll be a few unfortunates who metabolise it slowly or ineffeciently. So the recommendation to wait 24 hours seem to be a piece of "to be sure, to be sure" advice - after 6 hours, most people, most of the time, will have undetectable THC levels. But after 24 hours virtually everyone, all the time, will have undetectable levels.

At least, that's what it seems to me to be saying.

I thought that was the jist of what the Garda was saying

You should pass the roadside drug test after a nights sleep?

Peregrinus

It seems to be saying that the Drager unit shouldn't detect THC in oral fluid more than about six hours after last use - unless you are still feeling the effects of it, in which case (I'm guessing) that's a sign that your THC levels have remained high, and are likely to be detectable.

But that's shouldn't detect THC, not definitely won't detect it. There'll be a few unfortunates who metabolise it slowly or ineffeciently. So the recommendation to wait 24 hours seem to be a piece of "to be sure, to be sure" advice - after 6 hours, most people, most of the time, will have undetectable THC levels. But after 24 hours virtually everyone, all the time, will have undetectable levels.

At least, that's what it seems to me to be saying.

myfreespirit

cityboyjim wrote: »

Thanks for the reply .I had one smoke of cannabis .One joint that is .Is that enough to give high enough reading to convict me .I had some the previous night also.I was not expecting to have to drive that evening but felt fine and took the chance .Just no idea how to defend myself if I am charged with this .Thanks

The Road Safety Authority publishes a Frequently Asked Questions about roadside drug testing that the Gardaí carry out.
Link here:
https://rsa.ie/Documents/Campaigns/Anti%20Drug%20Driving/Preliminary%20Drug%20Testing%20List%20FAQs.pdf

These Q&A's talk about how long after smoking cannabis the roadside test can detect the drug:

Quote:

25. Can’t cannabis stays in your system for days after you smoke it?

The Drager Drugtest 5000 will detect 9-Tetrahydrocannabinol (THC), the active ingredient in cannabis, in oral fluid for about 6 hours after last use.

26. How can one be allowed to drive under medicinal cannabis if they have a note from their doctor, they are still impaired? It is expected that an extremely small number of drivers will be able to avail of the medical exemption certificate where their doctor lawfully prescribes them with a product which contains a medicinal cannabinoid. This certificate does not allow them to drive if they are impaired. Please see link to certificate here. A driver who tests positive for cannabis and is impaired is committing an offence.

27. I smoke cannabis regularly, how do I know when I am allowed to drive after taking it? It is recommended to wait 24 hours after last using cannabis before driving. If you are sure you are no longer impaired as result of taking cannabis and more than 6 hours have elapsed since last use it should not be possible for a Garda to detect impairment and the 9-Tetrahydrocannabinol (THC) level in you oral fluid should be lower than the detection limit for the Cannabis test on the Drager Drugtest 5000.

So, if I'm reading this right, it suggests that the Drager test can't detect the drug if you wait 24 hours after consumption before you drive.

Chicoso

There was a Garda quoted on the drug test , said you'd be alright the next morning

Means nothing though

Potential-Monke

joeguevara wrote: »

Prior to this, was she "feeling the effects"? :pac:

joeguevara

Funny story on this. A girl I know had a gram of coke and stupidly went drove to buy drink. Stopped at checkpoint when they first came out. Breathalised. Clear. Swabbed for drugs. Clear too. On the one hand delighted. But also furious she had been scammed.

Potential-Monke

Peregrinus wrote: »

the dilemma only arises because the science is inconclusive.

And yet they are basing the limit on inconclusive science, which to me, is not proper for legislation to be enforced. I'd have no problem if the evidence was there was a concentration of 1 ng/ml or higher coupled with evidence of impaired driving, whereas the way it currently stands, you're done either way. I don't smoke and drive, I treat it like drink, I won't smoke if I have driving that day, but I do smoke to unwind when I know I'm not going anywhere. With the current legislation, I would need to plan up to 3 weeks in advance, which is just not possible.

I won't get into the debate of drink vs weed, there's enough evidence out there to prove one is far more dangerous than the other. I dunno. I suppose I'll find out if I ever find myself in that situation, which hopefully I never will. Would be interesting to see if the law changes once cannabis is legalised, which I'm sure it eventually will be, when the younger politicians get into positions of power and realise the monetary benefit of it.

Peregrinus

With the current level of uncertainty, I think you have to plump for one of two approaches:

1. The precautionary approach: "Nobody needs to smoke dope. Therefore, we will not let people smoke dope and drive unless and until this is shown to be safe".

2. The [I can't think of a word which means the opposite of "precautionary"] approach: "Everybody needs to drive. Therefore, we will not ban smoking dope and driving unless and until this is shown to be dangerous".

Science can't steer you to one or other of these positions; the dilemma only arises because the science is inconclusive. So which way you jump must depend on some other factor. It could be your personal psychology - are you a risk-averse person or a more adventurous type? It could be personal interest or advantage - those who enjoy smoking will be motivated to prefer the approach which allows them to smoke and drive. It could be personal interest of a different kind - as a public representative, which approach is more likely to cost me votes/my seat? Or it could be a philosophical/ethical convictions - I would rather run the risk of inflicting unnecessary harm on cannabis users (by banning cannabis-driving when this may not be needed to protect the public) than on road users (by not banning cannabis-driving when this may be needed to protect the public) because the cannabis-drivers voluntarily put themselves in this position whereas the other road users do not.

Potential-Monke

Oh I understand totally. There's plenty research out there, but it's all inconclusive because of the way THC works in the body. It can't be compared to alcohol, which has a similar effect on all humans, with only some slight variance depending on age, size, etc. With THC, there are too many variables, and the 1 ng/ml doesn't appear to be a definitive number. As you said, I think they just went with the lowest possible number because they wouldn't have been able to find a definitive answer, which in itself is (to me) is not enough to make and enact a law upon.

I am open to correction, but I'd love to see the research/reasoning for this number to be used by the Irish Legislators, but I can't find it anywhere.

Peregrinus

It does seem to be the case that cannabis takes longer to metabolise than alcohol, and so cannabis use results in a longer period during which there is an elevated blood concentration.

But if the elevated blood concentration is in fact associated with a risk of impaired driving, that's not really an argument for allowing people to drive with a elevated blood concentration. It may be unfortunate for cannabis users that their drug of choice takes longer to eliminate from the system, but it's not a misfortune that they can ask others to bear on their behalf.

What this does is to raise the stakes on both sides, so to speak. If in fact 1ƞg/ml is associated with a risk of impaired driving, then the fact that a user may be at or above that level for several days after us makes it all the more important not to allow him to drive during that time; the longer the "risky period", the greater the chance of an accident.

On other hand, if it's not associated with a risk of impaired driving, then a restriction which prevents him from driving for several days after using is particularly harsh.

But this tells us nothing, one way or the other, about whether 1ƞg/ml is associated with an increased risk of impaired driving; it just underlines the importance of getting a definitive answer to that question. While you say that "the effects are completely gone . . . within 5-8 hours after smoking", the research you have been able to find doesn't seem to say that. And I should no more accept your word for this than you should accept my word that I'm just fine to drive the morning after a feed of pints and chasers.

Potential-Monke

Peregrinus wrote: »

...not so that they stop using cannabis, but so that they separate their cannabis use and their driving.

And therein lies the problem. Going by what I've been reading/researching, as I would be considered a 'heavy user' (more than 0.5g a day, also up in the air depending on THC levels in the strains being consumed), there's a good possibility that in a blood/urine test, I would be over the limit from 3 days to 3 weeks after stopping, as due to my 'heavy usage' it would take significantly longer for the level to drop below the 1 ng/ml stated.

I completely agree we need to have the laws, but this figure seems to punish those who smoke more, even though the effects are completely gone (similar to drink) within 5-8 hours after smoking.

I can only hope I don't get swabbed at a MIT checkpoint, because regardless of my driving I'll be prosecuted, be put off the road for 6 months and probably never be able to get insured again after that. Just seems unfair based on a figure that apparantly has no proper research behind it (or at least, has differing views/opinions on what would be considered too much to be over). Unlike drink, the heavy users still show under within 12-24 hours.

I haven't smoked in 4 days, but there's a possibility that if I'm swabbed today I could get prosecuted as I used to smoke daily, and quite a bit too.

Sorry for taking over your thread OP! Please let us know how you get on.

Peregrinus

I wouldn't assume that Ireland is copying Germany, since the same limit applies in Belgium, Denmark, Luxembourg and (in some cases) the Netherlands. And I think it also applies in most Australian states.

Ther's a couple of possiblities here, not necessarily mutually exclusive.

Ireland could have decided to go for a limit at the lower end of the range of limits used in different countries. While some countries have limits above 1ƞg/ml, few or none have limits below that. Irish legislators didn't want to appear "soft" on cannabis by comparison with other countries, so they adopted the limit that seemed to represent the toughest end of the range.

That just begs the question, though, why that figure has come to be the toughest end of the range.

It could be that, while there's a diversity of evidence about what level of cannabis concentration is associated with driving impairment, no evidence suggests that there is impairment below 1ƞg/ml, whereas there may be at or above that level. 1ƞg/ml therefore represents a very cautious approach; we won't accept any level of risk of driving impairment due to cannabis use.

Alternatively, 1ƞg/ml may represent the lower limit of what can be meaningfully measured. The view may be that, precisely because it's hard to identify a "safe" level of cannabis concentration, the correct approach is a zero tolerance approach: don't smoke and drive. 1ƞg/ml become the limit not because we know that it might be unsafe, but rather because we don't know that it's safe.

On either of these approaches, the confusion/difficulty about identifying the cannabis concentration that is associated with driving impairment becomes, not an argument for not punishing people with low levels, but an argument for not allowing them to drive.

It all looks a bit puritan, and it occurs to me that these approaches may be reinforced by the general illegality of cannabis use. But some of the countries with a very low level - notably the Netherlands - combine a relaxed attitude and liberal laws with regard to cannabis use and a hard line on cannabis-driving.

Be interesting to check if countries that have notably low cannabis-driving limits also tend to have notably low drink-driving limits.

A significant effect of the drink driving laws has been not to detect and punish drink drivers (though they do that) but to discourage drink driving in the first place by helping to bring about a change in attitudes (and they have been pretty successful at that also). And I think something similar may be at work here. The hope is that by taking a very strong line on cannabis-driving, the attitudes of cannabis users can be changed - not so that they stop using cannabis, but so that they separate their cannabis use and their driving.

Potential-Monke

Peregrinus wrote: »

So I think the question comes down to this; is there evidence of a statistically significant link in a material proportion of people between impairment to skills relevant to driving and the 1ƞg/ml limit? I don't know the answer to that question but, if you want to attack the law, I think that is the question you need to ask.

Good point, and from what I've been reading, the answer is no, there isn't. And t'internet is not helping me with regards to finding out who set these limits, how they came to the conclusion, and if all other factors were taken into account. Unlike alcohol in which "blood alcohol content (BAC) has similar rates of absorption, distribution, and elimination across all humans, and there is also a fairly good correlation between BAC and level of impairment", the same cannot be said of THC.

I've no doubt that whomever was behind this limit didn't actually do anything other than look at Germany and go, yeah, we'll use theirs (they test blood serum levels for the 1 ng/ml, unsure if that's what we do here). It just seems like this specific piece of legislation is severely lacking in research. And most likely the main reason it hasn't been challenged properly yet is because (and from experience) if someone (read: scrote) is driving under the influence, it's rarely just cannabis so while they might be able to fight that side of it, the other intoxicants would negate it.

Federal law in 'Merica sets blood/urine tests at 50 ng/ml and breath tests (ie: drugs intoxilyser, similar to the beath intoxilyser) have it at 15 ng/ml. Some states had a 'it's in your system so you're done sunshine' legisaltion, which was quickly removed/revoked/updated as it was constitutionally flawed (equal protection laws).

It's quite an interesting topic, but the ability to easily find the research behind Ireland's decision on limits is non-existent as far as I can tell.

Peregrinus

Potential-Monke wrote: »

They do already. The roadside test is not as specific usually, just indicates a level (with the Drager for drink, it used to show something like Zero, below and above iirc, but was changed to Yes or No or something similar) and the station test is the final determination. I'd imagine the same is also applied to drugs now.

I still think the arbitrary figure of 1ng/ml shouldn't be enough to convict alone. Would love if there was a case of someone challenging it on the grounds that it's too specific for something that can be (and has been proven) very specific to the individual.

To quote Ryan Vandrey, associate professor of psychiatry and behavioral science at John Hopkins University, "There is no typical window of detection. It is highly variable from person to persona and it varies based on the frequency of use and the amount of use. So there is no way of predicting or knowing how long someone would test positive with any kind of certainty".

I understand that that's the law, the judge has no say in it, I just find it strange that someone can be prosecuted on the 1ng/ml when there is so much evidence to prove that you can't put a figure on it. Surely if there was a legal argument to the law, the case couldn't be concluded without that being cleared first? Would the case not be put on hold if a valid argument was put against it, and wouldn't proceed until the law is upheld or amended? It's not much good putting someone off the road and possibly ruin their life because of an arbitrary figure with no scientific backing?

Does anyone have the research completed by the Irish Government, or at the least the studies they used, to come up with the 1 ng/ml? I don't even know what terms to search to find that. And do we know is it testing for THC, THC-COOH or OH-THC (the liver produced THC that everyone has)?

Similar questions could be, and no doubt have been, asked about the the permitted blood/alchohol concentration. Isn't this an arbitrary figure? Isn't it true that different people metabolise alcohol differently, may manifest different levels of impairment on the same blood/alcohol concentration, etc? And, yes, all this is true. But (the legislature takes the view that) it's still possible to say that, on average, a blood/alcohol concentration of 50mg/100ml is statistically associated with measurable impairment in driving skills, and therefore a general ban on driving in excess of that concentration is justified. And, so far, the courts have not seen fit to take the view that this is unconstitutional.

Given that, I think the fact that the effects of cannabis on driving-related skills vary from person to person is a complete non-runner as an argument against the law. There's a legitimate public interests in having clear and uniform laws, and in drivers knowing what is and isn't permitted, and if a material proportion of drivers are impaired at a given concentration, that justifies a ban and it's irrelevant that Joe Bloggs may not be impaired at that concentration.

So I think the question comes down to this; is there evidence of a statistically significant link in a material proportion of people between impairment to skills relevant to driving and the 1ƞg/ml limit? I don't know the answer to that question but, if you want to attack the law, I think that is the question you need to ask.

Potential-Monke

Carawaystick wrote: »

How does the Doctor get informed medical consent to take the blood sample? Given the Duress of prosecution for failing to give a sample?

By law, you've to provide a sample by signing a form for the doctor. If you refuse, you get charged with a separate offence of failing to provide a sample and it carries the same penalty as if you were charged with being over the limit.

Carawaystick

How does the Doctor get informed medical consent to take the blood sample? Given the Duress of prosecution for failing to give a sample?