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Development of the Marijuana Breathalyzer: A Speedbump in Legalization

Larry Rankin is a non-user who is fascinated by the ins and outs of the ongoing marijuana legalization process.

It would seem the tide has turned in the marijuana legalization debate. Unlike in years past, pro-legalization seems to have all the momentum, and it should. Everything out there that is credible has shown the effects of marijuana to be less destructive than many legal drugs, such as alcohol, tobacco, antidepressants, etc. From the standpoint of a safer high, there just isn’t any obvious, rational reason why marijuana shouldn’t be legalized.

That is until we get into the practicality of legalizing it. Marijuana is like a round peg in a square world: it just doesn’t want to fit. For example, it can be grown naturally, so anyone can grow it in their backyard, which makes regulation and taxation a bit of a headache, but perhaps the biggest problem with legalizing Marijuana is the fact that it stays in your body so long.

Most drugs leave the body within a day or less after use. Yet it is not unusual for THC to embed itself in the user’s fat cells for over a month. There have even been cases in which heavy users have stopped and THC is still present as much as a year after cessation. (1)

The problem this presents is in monitoring if users are under the influence when they shouldn’t be: behind the wheel, at work, etc.

The Shortcomings of the Blood Test

With alcohol there is the simplicity of the roadside breathalyzer, a tried and true system for measuring one’s sobriety. Though there are currently myriad companies chasing the perfect roadside marijuana tester, with many like Hound Labs in California claiming success, we are still a long way from an established pedigree that will hold up under the scrutiny of law. (2)

We do have the certainty of blood tests to determine if someone has enough THC in their system to be deemed “high,” but a blood test can only effectively be used after the fact, not for the prevention of marijuana related accidents. (1) For example, a roadblock can catch drunk drivers before potential injury and the loss of life because of the breathalyzer. A blood test would likely only be of relevance in casting blame after the incident occurs.

And that is if you believe marijuana significantly hinders one’s ability to drive. And what is “high,” anyway?

How Marijuana Impacts the Senses

The prevailing scientific literature indicates that marijuana doesn’t much hinder the performance of singular tasks, but given multiple tasks, such as is almost always the case in real world scenarios, the marijuana user is prone to distraction. This is all in large part due to the fact that the marijuana user’s brain is more active than a non-user. All this unnecessary activity causes problems with things like peripheral vision, understanding the passage of time, multi-tasking, and even balance. (1)

These are all senses that we use to keep our vehicles on the road. That said, some studies have shown that people under marijuana’s influence are (at least comparatively) safer than drivers under the influence of alcohol. This is because people who are high on marijuana tend to be aware of that fact, while those inebriated by alcohol do not. (1) In essence, the research shows that marijuana users are more careful drivers than those who are drunk.

Due to the effect on the senses, prudence dictates that people should not drive while high, but for argument’s sake, let’s say that marijuana was proven to not be a significant hindrance to everyday driving: what about activities like driving semis or buses or large equipment?

A double-standard regarding acceptable inebriation levels based on the nature of equipment being used is not without precedent. For example, truck drivers with a BAC above trace amounts (say more than what a person may accidently ingest while using mouthwash) will be given a DUI, while a person of average size can operate their personal vehicle after a couple of drinks with no fear of repercussion. This is because a semi requires more concentration to operate safely than a normal sized vehicle.

But whether it is decided we need to detect inebriation levels for drivers of all vehicles or just some, marijuana represents a regulatory problem. THC is still in the body well after use, regardless of whether or not a person is actively stoned. Testing preventively is very difficult. The current answer is to allow employers to determine whether or not any THC is acceptable for employment based on vocation type, but as legalization becomes the rule and not the exception, this becomes an unreasonable restriction.

How can a business justify telling employees what they can or can’t ingest away from work and off duty if it is a legal substance? For example, a doctor on call is required to stay sober because while on call they could be asked to perform at any moment. The employer is justified in making this requirement for the safety of patients. However, Doctors are not forbidden to ever drink alcohol, because it is a legal activity that can be enjoyed safely by adults.

The same is true of marijuana, and as it becomes entirely legal, the lack of a marijuana breathalyzer and the nature of THC to stay in our body will make determining who is high a real challenge.

How Far Away is a Breathalyzer System?

Most authorities on the matter agree that it is just a matter of time before a reliable roadside marijuana “breathalyzer” is developed, and it is conjectured by many that the winning system won’t even measure breath, but saliva.(1)

Whatever ends up being the prevailing system, the next obstacle will be proving its reliability, which will likely also take years, and then it is a matter of training law enforcement to use it properly, which again adds to the projected release date of an effective system.

Just to add a little perspective, Dr. Marilyn Huestis, a leading researcher on the effects of marijuana, projected regarding a roadside marijuana test that, “we’ll see these kinds of tests used by law enforcement…within 3-5 years.” (1) This projection was made in a Popular Science article written 4 years ago.

It isn’t even so much that the technology to test THC levels on the spot doesn’t currently exist; it’s that such systems don’t lend themselves to accurate use outside a controlled laboratory with uncooperative test subjects. In a knee jerk reaction, Australia even implemented a saliva-based roadside Marijuana Test way back in 2004. Though it was based on a system that worked well in the laboratory, the roadside version proved to be virtually useless. (1)

How High is High?

But when a reliable roadside test is finally developed, we still have the major issue of determining exactly what it is to be under the influence of marijuana. All regular users will have THC in their system at all times, regardless of whether they are high or not. As a result, the threshold can’t be zero.

So how much THC represents being high? Both Colorado and Washington have decided this number is 5 nanograms or more per milliliter of blood. (1) And what hard science is this based on? When you dig into the data, you find out it’s a guesstimate. They’re using quasi-science to make an educated guess at the threshold in which both regular users and occasional users will be significantly impaired.

But though this number is fairly arbitrary, it’s a jumping off point. The same is true with alcohol. We don’t really know what level makes a particular individual drunk. The threshold used to be .1 BAC for a DUI. Now most states have it at .08. This number isn’t based on any hard science. A first-time drinker driving legally at a BAC of .07 might be lit and a hazard to others, while a seasoned drinker driving illegally at .1 BAC may drive safely. (1)

With this sort of thing there has to be a starting point. There has to be a set level that we can agree upon as being “in the ballpark” of correct, even though drugs, whether it be alcohol, tobacco, marijuana, or Tylenol, affect everyone differently. 5 nanograms today may be changed to 3 or 7 with the perspective of time.

Final Thoughts

The lack of a marijuana breathalyzer is a bona fide obstacle to legalization. Unlike all the same old nonsense that anti-marijuana legalization activists continue to repackage and regurgitate, trying to bide time before the inevitable, this is a problem not imagined or exaggerated that will take time and effort to entirely overcome.

That said, the train remains on the rails and continues to chuck along. Breathalyzer systems will continue to develop and refine. Regulatory measurements will continue to be honed and adapted for increased relevance and accuracy. We will make marijuana fit because it is far less costly than its exclusion.



1. “How Will Police Regulate Stoned Driving?” Popular Science [online]

2. “Don’t Hold Your Breath for a Marijuana ‘Breathalyzer’ Test” Scientific America [online]

This content reflects the personal opinions of the author. It is accurate and true to the best of the author’s knowledge and should not be substituted for impartial fact or advice in legal, political, or personal matters.


Larry Rankin (author) from Oklahoma on September 04, 2017:

Nadine: thanks for dropping by. So glad you enjoyed it:-)

Nadine May from Cape Town, Western Cape, South Africa on September 04, 2017:

What an interesting article Larry, very informative. Never heard about a marijuana breathalyzer.

Larry Rankin (author) from Oklahoma on August 14, 2017:

Catherine: I also feel it makes it a lot easier to legalize in good conscience.

Thanks for stopping by.

Catherine Giordano from Orlando Florida on August 14, 2017:

I had not heard about a marijuana breathalyzer before, but I instantly recognized it as a good idea. It will make people less likely to drive when high. Even certain medications can impair the ability to drive. (It says so right on the label.) You made a very persuasive case. I'm in favor of it. It puts marijuana in the same legal place a alcohol.

Larry Rankin (author) from Oklahoma on June 24, 2017:

Fullerman: I agree with your sentiments. Thanks for stopping by.

Ryan from Louisiana, USA on June 23, 2017:

Some good points here. If it becomes legal, which it should, we definitely need certain legal restrictions on it like alcohol or tobacco. Very interesting hub.

Larry Rankin (author) from Oklahoma on June 23, 2017:

Katy: I think the fact that we're discussing more intricate issues like Marijuana breathalyzers shows we're close to legalization.

Thanks so much for dropping by.

Larry Rankin (author) from Oklahoma on June 23, 2017:

Nadine: thanks for stopping by.

Larry Rankin (author) from Oklahoma on June 23, 2017:

Ronnie: of course the 87% matters. That's why we have driver's education.

Let's try this 1 more time. When less than 1% of drivers (in this case drunk drivers) cause 13% of all accidents, focus on that group! No other group represents a larger danger to drivers than those intoxicated, and unlike other accidents, drunk driving accidents are 100% preventable.

As to the other topics you brought up, they're legitimate concerns, though off topic. Do we have tolerance levels and punishment where they should be concerning DUIs. That is always up for debate.

Police have always been susceptible to corruption. This is a very multidimensional topic for another day. But again, the topic at hand is the development of a marijuana breathalyzer. We're getting off the scope of the article again.

Caila Ingram from United States on June 22, 2017:

This is a great article and a hot topic in my home state of Maine. Now that marijuana has been legalized everyone wants to know how the state is going to enforce the DUI laws. Personally, i never thought legalization of Marijuana would happen in my time, but now that it has I don't think it will take to much longer for instant marijuana testing.

Nadine May on June 22, 2017:

What an interesting article on marijuana. I did not know the effect it has on people...I learned a great deal.

Ronnie wrenchBiscuit on June 16, 2017:

Larry, 87% is no laughing matter. What I have suggested is a practical remedy. Furthermore, anyone familiar with the corruption of law enforcement understands that because the limit is now set so low, a great majority of those who are charged with DUI are not a threat to anyone. When someone you love is killed by a sober driver please remind yourself that the 87% doesn't matter.

Larry Rankin (author) from Oklahoma on June 14, 2017:

Linda: I'm always glad to hear from you.

I think I've done the facts justice here.

Larry Rankin (author) from Oklahoma on June 14, 2017:

Ronnie: lol. Good for a laugh, anyway.

If we want to legalize marijuana, a marijuana breathalyzer is a critical building block to that end.

Your statistics are a false equivalency. If 13% of accidents are caused by well less than 1% of the driving demographic on the road at any given time, than yes, we definitely need to protect our citizens from these people! Roadblocks, breathalyzers, and most importantly education.

When I was a young man I got a DUI. No complaints here. I was endangering lives. I needed pulled off the roads for 6 months.

Larry Rankin (author) from Oklahoma on June 14, 2017:

Kara: that's my standpoint. Some marijuana activists view the development of this device as a step backwards. Why? In my mind the opposite is true. A good breathalyzer makes legalization nationwide that much more practical.

Thanks so much for stopping by:-)

Larry Rankin (author) from Oklahoma on June 14, 2017:

Bill: you're always going to have growing pains, but we're on the right path.

Larry Rankin (author) from Oklahoma on June 14, 2017:

CJ: I always appreciate when you drop by. Thanks so much for sharing.

It's a real problem. I didn't include it here, but pot related DUIs have apparently more than doubled in states where it's legal.

A roadside test is definitely needed, but I still think we're on the right track with legalization. I don't want this to become an anti-marijuana article. I just want to bring things back to earth and show there are some practical obstacles.

Linda Crampton from British Columbia, Canada on June 13, 2017:

This is a very informative article, Larry. You've given me some important things to think about. Thank you for sharing the facts.

Ronnie wrenchBiscuit on June 13, 2017:

Interesting article. I never thought about this, but I should have. I should have figured greedy politicians and city officials would figure a way to extort more money from citizens.

We don't need a marijuana breathalyzer, and we could do without them period. 87% of auto fatalities are caused by sober drivers! If the government really wanted to save lives they would invest more in mass transit and limit the usage of automobiles. In the Navy we were given Top-Secret clearances on a "need to know" basis. Driving should also be determined on a "need to drive" basis. But cities are making billions of dollars on DUI penalties. And all of those on the gravy train are making bank as well. It's the automobile that is killing the majority of people, not drunk drivers. Anyone who supports marijuana breathalyzers is supporting tyranny, and is an enemy of the people.

Kara Skinner from Maine on June 13, 2017:

This was a great article. I've never thought about a marijuana breathalyzer, but you are right. These do need to be developed for the safety of everyone involved. Developing a way to accurately test for "highness" would also probably help legalize marijuana because people could relax knowing there are ways to monitor drivers and workers to make sure they are not high.

Bill Holland from Olympia, WA on June 13, 2017:

Great points, Larry! When Washington State, where I live, legalized pot, it took over a year to work out the legalization of it so the system would function. It is truly a difficult legal situation.

CJ Kelly from the PNW on June 13, 2017:

Larry, great work. Very important topic in my state since legalization. DUIs are up but I don't know a breakdown of which substance. 3-5 years is too long to wait. We need them much sooner.

I've known several people who still claim they drive "better" when high. Yeah...


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