Legalization of Marijuana

Earlier this week voters in Colorado and Washington state approved ballot measures legalizing recreational use of marijuana. While similar proposals have fallen short of approval in California, it is reasonable to surmise that other states will follow, and a trend will emerge.  Supporters are applauding the end of "prohibition," likening this development to the adoption of the 21st Amendment to the United States Constitution in 1933, repealing the 18th Amendment (1920).

As you know if you read my essay "Temperance and the Addict" last June, I have an academic interest in the use of mood-altering substances, and the effects of changing the status of marijuana from illegal to legal will surely be fascinating to observe.

["Medical marijuana," by the way, is a subject to which I haven't paid much attention, because I think the scientific literature on that is more confusing than enlightening, and I have been inclined to agree with those who perceived the movement to legalize the drug for medicinal purposes to be nothing more than a smokescreen (pun intended) for legitimizing recreational use.]

In the practice of emergency medicine I frequently see the consequences of the choices people make about the use and abuse of tobacco and alcohol.  Much has been written comparing marijuana with those two legal drugs.  Even an overview of those comparisons would take a book chapter rather than an essay.  For example, the long-term health effects of tobacco and alcohol are well understood. Marijuana, not so much.

A column ("The End of the War on Marijuana") published at CNN.com caught my eye early this morning.  The writer, Roger Roffman, is a professor emeritus of social work at the University of Washington and a supporter of the legalization measure in that state.  Roffman made two observations that I found especially noteworthy:

Far too many teens think smoking pot is "no big deal," greatly underestimating the risk of being derailed from social, psychological and educational attainment. Far too many adults don't take seriously enough the risk of marijuana dependence that accompanies very frequent use.

Roffman has written books on medicinal marijuana and the treatment of marijuana dependence, and his next book (titled A Marijuana Memoir) is sure to be interesting.  It's my sense that he knows his subject well, and so his observations worry me more than a little.

One of the aspects of substance use that I often think about is direct cost to the consumer.  While the price of a pack of cigarettes varies with state taxes, not to mention choice of brand versus generic or purchase by the pack or carton, I have a pretty good idea what people are spending on tobacco when they tell me how much they smoke.  I cannot help being amazed that some people whose resources are very limited choose to spend thousands of dollars a year on cigarettes.

It was my sense that prices for marijuana are quite variable, and a Web search for information proved that to be correct.  I found a wide range of reported "retail prices," mostly between $200 and $1,000 per ounce.  Knowing next to nothing about smoking the stuff, I did more research to discover that people typically roll joints containing anywhere from one half to one gram each, which means one might get anywhere from 30-60 joints from an ounce.  At $300/ounce, a joint might cost $5 to $10.  This was an eye opener for me.  I had figured marijuana was much more expensive than tobacco per cigarette, but I didn't realize one joint cost as much as a pack of cigarettes.

Of course, users don't typically smoke 20 joints per day.  As I browsed the Web, the self-reported patterns I found for regular users were mostly in the range of 1-5 grams per day, with one person claiming 15 grams per day when he had large amounts of money (and could afford to spend large amounts of time completely disconnected from reality).

So the bottom line on the expense for regular users seems to be about the same as for a pack-a-day cigarette smoker at the low end (one joint per day) to much more than that (perhaps $50/day) for heavy users.  I'm guessing the heavier users likely are able to get better prices by going up the supply chain and paying wholesale prices.  Smoke what you want and sell the rest.

We know a lot about the damaging effects of smoking tobacco on health: heart attack, stroke, peripheral arterial disease, COPD, and lung cancer, just to name the most common problems.  We know far less about what regular heavy smoking of marijuana does to the lungs, but I think we are likely to have much more data in the years to come.

We also know a good deal about the harmful effects of alcohol, including disease of the liver and other organs in the digestive system as well as the brain.  In emergency medicine, while we see plenty of that, we see a great deal of trouble caused by acute intoxication, especially motor vehicle crashes.

So I wanted to find out how smoking a reefer might compare with alcohol consumption for getting behind the wheel.  As you might imagine, the data are not abundant (yet), but here is what the National Highway Traffic Safety Administration (NHTSA) says:

Marijuana has been shown to impair performance on driving simulator tasks and on open and closed driving courses for up to approximately 3 hours. Decreased car handling performance, increased reaction times, impaired time and distance estimation, inability to maintain headway, lateral travel, subjective sleepiness, motor incoordination, and impaired sustained vigilance have all been reported. Some drivers may actually be able to improve performance for brief periods by overcompensating for self-perceived impairment. The greater the demands placed on the driver, however, the more critical the likely impairment. Marijuana may particularly impair monotonous and prolonged driving. Decision times to evaluate situations and determine appropriate responses increase. Mixing alcohol and marijuana may dramatically produce effects greater than either drug on its own.

I must admit I find this more than a little scary if legalization makes smoking and driving anywhere near as common as drinking and driving is now.  And drinking and driving would likely be much more common if it were not for fairly strict enforcement of laws against that.  Will we have laws against driving under the influence of marijuana in all the states where recreational use is legalized?  How will such laws be enforced?  There is no recognized field sobriety test or breath test, and the correlation between blood levels and clinical effects is very uncertain.

One news story about the new law in Colorado said the state expected, through the regulation of sale and the imposition of taxes, to bring about $60 million a year into the state treasury, while saving about $75 million in costs to the penal system associated with the criminalization of sale, possession, and use of marijuana. That's a lot of money going to the state's bottom line.

The obvious question: will it be worth it?  The answer: we don't know, because we have no way to calculate the cost of much more widespread use resulting from its effects on health and behavior.  If the record of tobacco and alcohol is even modestly instructive, we may be in for some rude surprises.  As my regular readers know, I think we do an awful lot of things in our society as if we have never heard of the Law of Unintended Consequences.