What is the rationale for Driving with Measurable Amount laws for those under 21

Maybe it is because of the holidays, but I am seeing an increase in clients charged with Driving with a Measurable Amount of Alcohol Laws. Basically, those laws state that anyone under age 21 who drives with a measurable amount of alcohol in their bloodstream (in my state .02 BAC) is charged with a DUI and subject to penalties.

To me, this law conflates and confuses two different public policies (also laws) and results in absurd consequences. First, we agree (for the purposes of argument) that people under age 21 may not consume alcohol. We further agree that persons who drive automobiles under the influence of alcohol should not be driving.

These laws seem to pound a round peg into a square hole. If you pull over a 20 year old with a .03 BAC, then you have an excellent case that he has consumed alcohol in violation of the underage drinking laws. However, he is not operating an automobile while impaired. So, I’m not sure why the vehicle part is relevant.

Why should a person who drinks underage and drives non-impaired be subject to enhanced penalties? What is the logical purpose of these laws?

I dont believe that there is a law saying minors cant consume alcohol. Who would have the jurisdiction over that? There are laws against minors purchasing alcohol, and adults supplying it to minors, but that doesn’t relate to driving. States do, however, have jurisdiction over who can drive a vehicle and in what shape they have to be in.


Many states have laws that say minors cannot consume alcohol. All states may regulate driving. I was asking about the logic of it, not the power to enact it.

I don’t believe it’s always an absolute that states prohibit drinking of under 21 in all cases. I think that parents are allowed to give their own children alcohol. For example, in Illinois

Because for the sake of argument we’ve agreed that persons under age 21 may not consume alcohol?

I really don’t understand your logic here. We’ve agreed that the legal drinking age is 21. And a cop has pulled a driver over for doing something questionable (speeding, weaving, running a stop sign, whatever.)

Is it logical for the cop to wonder if the driver is drunk? Probably.

Is it logical for the driver not to admit they’re driving drunk? Absolutely.

Is it logical to test them? Considering the above, yes.

So why is it not logical to charge them with a DMA? Especially since if there’s one thing a 20-year old driver has had pounded into his head since he got his license, it’s DON’T DRINK AND DRIVE.

And, by your own admission, you’re seeing an increase in cases where this is happening. I need a better explanation why you think this is a bad idea.

37 states, including yours of WV, allow minors to drink either at home or with their parents. So having measurable amounts of alcohol in your blood is not a crime, you could have been drinking at home. And if you’re under the legal limit you’re not DUI. So this law covers this situation.

You’re premise is wrong. It is not illegal for a minor to drink in all circumstances.


Michigan has such a law. We also border a province where the drinking is 19. Thus it’s quite possible to consume legally, remain sober enough to drive, and be affected by the silly law.

I don’t know of a different way to say it. There is no societal evil of “drinking and driving.” Nobody suggests that the amount of alcohol a person may consume and then drive is ZERO. Even if some madd mothers want that it has not been enacted. So, as I said, there are two societal evils here:

  1. We do not want young adults under age 21 to drink.
  2. We do not want people to drive impaired (not zero tolerance, only impaired driving).

If a person under age 21 drinks, then he violates social policy #1, but we are punishing him as he has violated social policy #2 as well, when he clearly has not. If you want to argue for a zero tolerance driving policy for everyone, then that is a different debate, but if someone is not driving drunk at age 20, then social policy #2 is not violated anymore than a person age 48 is while DMA.

But these kids get their license suspended, have to go to alcohol classes, etc. for something that society implicitly admits is not a danger. Again, I have no problem with a citation for underage drinking in these circumstances, but I do not understand the logic in imputing that behavior to irresponsible driving.

Actually, commercial drivers(semis and straight trucks) face exactly that.

I think the logic is this: Young people are inexperienced drivers and inexperienced drinkers. Together, that’s a recipe for disaster.

Personally, I favor a return to the 18 year-old drinking age.

Fair enough, but that has not been extended to passenger vehicles. Whether it should be as the poster above seemed to suggest is another debate. If a 48 year old is not endangering the public by having one or two drinks and then driving, a 20 year old is not as well.

Okay. So the argument is that because I have been driving for 30 years, I can handle having one or two drinks in my system, but because this kid has only been driving for 4 years, he needs his full faculties to concentrate on the road? It seems pretty pretextual and would probably pass the rational basis test in court, but I’m not buying it.

If anything, this kid’s reaction time is much better than mine, and if we follow that logic to its conclusion, we should ban anyone over the age of, say, 65 from driving at all.

As far as the inexperienced drinking, there is still the general intoxicated driving law. If .02 BAC puts you on your ass, regardless of age, you can still be charged with DUI notwithstanding the BAC. That applies whether one is 16 or 86. I don’t see the need to single out young people for this.

I dispute your first point. It is not illegal to furnish alcohol to a minor in WV so long as you are related to the minor by blood. However, in the wisdom of our Legislature, it is still illegal for the minor to consume or possess the alcohol. The police hit on this portion of the law a lot.

But it any event, let’s assume that it is not illegal for a minor to drink in some circumstances. Why is the driving part important when impairment is not an issue?

The “inexperienced drinking” doesn’t mean that .02 puts you on your ass. It means that an inexperienced drinker is less likely to know how many drinks will result in intoxication for that person, so best if they don’t drink at all if they are going to drive.

Also, there 's no reason to assume that a 20 year old has been driving for 4 years, or even that the person charged for driving with a .03 BAC is 20 rather than 16. So instead of

it could easily be a 20 year old who has had a license for two weeks or even a 16 year old who has had a license for 2 weeks. Are you still not buying it?

To your first point: If they are pulled over and charged with DMA, then they have successfully navigated the difference between reasonable drinking and intoxicated (or else they would be charged with DUI). We want to punish that? To the contrary, we want to encourage that.

Second point: The experience level does not matter so long as the driving is not impaired. The dangers of drunk driving, AFAIK, are because of the delayed reaction time, not because of any lack of knowledge or experience. We should ban driving over age 65 under the logic of these laws.

Have you, in fact, established that young drivers are “impaired” only if their BAC reaches the threshold established for adult impairment?

Adults tend to have more body mass (as well as more experience driving and more experience drinking, as noted previously). Teenagers are known scientifically to have different sleep requirements from adults and different judgment than adults – are you sure their alcohol tolerance and driving ability are identical to adults?

The legislature, of course, probably doesn’t have science backing its position. This is a visceral response like the laws we make regarding terrorists. Teenage drivers, not entirely unlike terrorists, keep killing us. Some sort of response from lawmakers and police is inevitable.

Well, first, I think it is on the proponents of a law in a free country to show the harm before restricting freedom. I don’t think it is my duty to show how a law is bad at the outset.

But to your point, I don’t think the Legislature could show that. Sixteen or twenty year olds are more capable, as a rule, than 40 year olds. When I was sixteen, I could get out of bed by placing my hard dick on the floor and pogo-sticking to the bathroom. Today, well (deleted) it is much different.

To say that young people are less capable of a physical task of driving a car than older people is a specious argument at best. The body mass argument is even more absurd. Some fat 20 year old is held to a higher standard than a 42 year old that just went to the gym because his doctor told him he was about to get diabetes?

Your final paragraph seems to suggest that your prior arguments are complete horseshit, to which I wholeheartedly agree. :slight_smile:

It looks like the limit for CDL holders is 0.04, not zero . I’m not clear whether an 0.04+ results in a suspension of CDL privileges AND DUI arrest or just the suspension.

Interestingly, a .04 will cause a loss of CDL even if caught while driving a passenger vehicle.

I would think the argument is more that there are contributing factors that have been shown to increase the possibility of an accident. For example, many states do not allow drivers of a certain age (usually 16 YO) to have more than one non-family member as a passenger in the car. That seems quite reasonable considering the distractions that a car full of teenagers might create for a less-experienced driver. Many states have decided that underaged drivers should be strongly discouraged from driving after consuming any alcohol at all. (Similarly, some states also prohibit young drivers from driving after dusk.) It doesn’t seem at all unreasonable, and I don’t exactly see why it has to meet your criteria of “both A and B must be true” before it’s rational. Just my opinion, of course.

BTW Utah just became the 1st state to lower the DUI limit to 0.05