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March 27, 2014

New study suggests legalizing medical marijuana may reduce violent crime

This new Washington Post piece, headlined "No, legalizing medical marijuana doesn’t lead to crime, according to actual crime stats," a notable new study provides reason to think (or at least hope) that medical marijuana reforms may actually be a crime reduction strategy. Here are excerpts from the Post posting, with links to the study being discussed:

Actual historic crime data, however, suggest there's no evidence that legalizing the drug for medicinal purposes leads to an increase in crime. In fact, states that have legalized it appear to have seen some reductions in the rates of homicide and assault.

These findings come from a nationwide study published Wednesday in the journal PLOS One (which is notable for the fact that no one seems to have done this crucial analysis before).  Researchers at the University of Texas at Dallas looked at the FBI's Uniform Crime Report data across the country between 1990 and 2006, a span during which 11 states legalized medical marijuana. Throughout this time period, crime was broadly falling throughout the United States.  But a closer look at the differences between these states —  and within the states that legalized the drug before and after the law's passage — further shows no noticeable local uptick among a whole suite of crimes: homicide, rape, robbery, assault, burglary, larceny, and auto theft.

The robbery and burglary findings are particularly interesting, as those are the crimes we'd most likely expect to see outside of medical dispensaries.  But what about the apparent declines in homicide and assault?

The researchers, Robert G. Morris, Michael TenEyck, J.C. Barnes and Tomislav V. Kovandzic, caution that this may be a mere statistical artifact of their analysis. But there's also a plausible explanation:

While it is important to remain cautious when interpreting these findings as evidence that MML reduces crime, these results do fall in line with recent evidence and they conform to the longstanding notion that marijuana legalization may lead to a reduction in alcohol use due to individuals substituting marijuana for alcohol. Given the relationship between alcohol and violent crime, it may turn out that substituting marijuana for alcohol leads to minor reductions in violent crimes that can be detected at the state level.

Their analysis controlled for other potentially confounding factors: employment and poverty rates in each state, income and education levels, age and urban demographics, per-capita rates of prison inmates and police officers, as well as per-capita rates of beer consumption (per the Beer Institute).

The results don't definitely prove that medical marijuana has no effect on crime (or that it might even reduce it). Maybe the researchers failed to account for some other crucial variable here, some common factor that further depressed crime in precisely these 11 states, precisely after the moment that each passed a medical marijuana law, masking the actual crime increase caused by the policy. Or, there's this interpretation, from the authors:

Perhaps the more likely explanation of the current findings is that [medical marijuana] laws reflect behaviors and attitudes that have been established in those societies. If these attitudes and behaviors reflect a more tolerant populace that is less likely to infringe on one another’s personal rights, we are unlikely to expect an increase in crime and might even anticipate a slight reduction in personal crimes.

March 27, 2014 at 11:39 AM | Permalink


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This makes sense. Consider that according to Homer, at the time of the visit of Odysseus, "the island of the Lotus-Eaters reported virtually NO crime"! See Odyssey Chapter IV, lines 27-33. Regretfully this sentence is found only in the original Greek edition. For inexplicable reasons, the sentence has been left out of every English translation.

Posted by: classical scholar | Mar 27, 2014 11:53:02 AM

"New study suggests legalizing medical marijuana may reduce violent crime."

Did anyone ever say "medical" marijuana in particular INCREASED violent crime?

The problem with "medical" marijuana is (1) that its often just a front for your normal, get-blasted marijuana, and therefore dishonestly represented; and (2) that it decreases ANY activity that might conceivably be productive, like diligent and focused work, for example.

P.S. People don't commit crime either because they're blasted or drunk. They commit it because they're greedy, think rules (and normal jobs) are for suckers, and have no empathy for the people they steal from. It's not a failure of sobriety. It's a failure of conscience.

Posted by: Bill Otis | Mar 27, 2014 12:48:13 PM

to: classical scholar,

Very funny!

Posted by: greek scholar | Mar 27, 2014 12:58:16 PM

To the degree medicinal marijuana, like other medicine, helps those who take it, it promotes their ability to "be productive, like diligent and focused work" as compared to suffering the ailments being medicated.

As is not arresting an arbitrary number of people who uses marijuana, even if it doesn't result in continual imprisonment, with resulting negative effects, including in some cases lost of certain benefits. That sort of thing lessens being productive in various ways, as does allowing people to drink from time to time, w/o tossing them in jail unless they commit a violent crime etc.

I'm assuming the stuff is useful to that end, which has long colloquial evidence. It might be a "front" to "getting blasted" (to the degree usage is "getting blasted" like having a glass of wine w/o being arrested or breaking the law means the same ... if we want to be clear on what people are saying here) for "many." But, "many" also seriously consider it medicinal, even if they might be misguided. Also, like wine, not sure the limits of "medicinal" really. If it is "merely" being used for relaxation, it might not be "medicine" exactly, but it is a historical usage of alcohol to ease tensions etc.

I do think many people who support criminalization of drugs are not just doing it for moral reasons or to advance productivity (reasons behind the 18A too). They believe that it is increases crimes. But, it is somewhat circular (it is illegal, which makes usage criminal) and once you make a common activity criminal, it is likely to increase crime in other ways as the now criminal class has less respect for following the law. If the practice actually is particularly dangerous to society, some of this might have to be balanced in the mix, but marijuana (much less so than certain drugs like heroin) is not.

And, though there are broad arguments that illegality of drugs as a whole is problematic, such libertarian principles isn't what are at stake here. In the real world, a middle path is taken. And, given that, marijuana legalization is a good idea, in part because it does not increase crime and might in fact reduce it in some ways.

Posted by: Joe | Mar 27, 2014 1:14:16 PM

It isn't really germane to this post, but criminalization of marijuana is problematic in part because it is enforced arbitrarily. Maybe it is, since some medicine is seen as acceptable, even given its strong effects, while other are not.

Anyway, I again note that I have my doubts that the net benefit in reducing crime will be large enough to affect the argument for marijuana legalization overall. But, it helps to show why criminalization itself is a bad idea.

Btw, the "Beer Institute" is just as you expect by its name.

Posted by: Joe | Mar 27, 2014 1:20:09 PM

Bill, fans of music, art, and literature might disagree with your definition of "productive" activity. Certainly, we owe some of the best music of the past 50 years to marijuana.

Posted by: Curious | Mar 27, 2014 2:26:44 PM

Classical & Greek scholars:
I am offended by your illiberal acts of micro-aggression.

As the eminently progressive scholar, Rep. Barbara Lee (D-CA), a member of the Congressional Black Caucus, might have said:
"[These] comments “are a thinly veiled racial attack and cannot be tolerated,” Lee said in a statement Wednesday afternoon.

“Let’s be clear, when [classical scholar] says ‘[Odysseus],’ when he says, ‘[Lotus-Eaters],’
these are simply code words for what he really means: ‘[Greek].’”

~~ thinkprogress.org/politics/2014/03/12/3398771/african-american-representative-slams-paul-ryan-for-racially-charged-comments/

Posted by: Adamakis | Mar 27, 2014 2:40:11 PM

Curious --

"Certainly, we owe some of the best music of the past 50 years to marijuana."

And some of the "best" automobile wrecks.

P.S. Still, since it's such a positive force, I trust you're going to start your kid on it. Maybe at age 12? Earlier? Yes?

Posted by: Bill Otis | Mar 27, 2014 3:04:10 PM


You're absolutely right that marijuana is dangerous if used irresponsibly, and I wasn't denying that. Instead, I was questioning your assertion that marijuana "decreases ANY activity that might conceivably be productive," which is plainly wrong. We owe marijuana car wrecks as well as great creative inspiration. We can and should acknowledge both when we think about marijuana policy.

And no, I wouldn't start my kid on marijuana, despite the fact that I think its a positive force, just like I wouldn't want my kid having sex, driving, owning a firearm, or drinking alcohol, even those things all have positive potential forces as well. But come on, you knew the obvious counter-argument to your point when you made it.

Posted by: Curious | Mar 27, 2014 3:22:18 PM

Bill, in addition to being pleased that Curious has taken down your hyperbole, I am curious if you would become a support of medical marijuana reforms if (when?) we had reasonable evidence that such reforms may in fact reduce violent crime a bit. You are very vocal and very effective in highlighting why you think reductions in violent crimes serve as a string justification for mass incarceration AND you maintain that position forcefully even when there is some significant evidence that alternatives to incarceration may be perhaps more effective and certainly much cheaper.

Given your forceful advocacy, Bill, that just the possibility of reduced violent crime justifies diminished liberty through mass incarceration, I wonder if you would also say the possibility of reduced violent crime justifies increased liberty through medical marijuana reform. At the very least, would you credit the possibility that persons (like me) who generally are supportive of increased liberty through marijuana reform are reasonable for hoping that reduced crime could be a benefit of ending pot prohibition (just as proved to be a benefit of ending alcohol prohibition 80 years ago).

Posted by: Doug B. | Mar 27, 2014 3:48:03 PM

Curitous writes: "Certainly, we owe some of the best music of the past 50 years to marijuana."

I know I'm dating myself, but, under certain conditions, I still enjoy the original version of "Ina Gadda Da Vida."

Posted by: Michael R. Levine | Mar 27, 2014 4:02:40 PM

Curious --

You fail to give any actual reason you wouldn't want to start your kid on pot. If it's a "positive force," as you maintain, why WOULDN'T you want him on it? And if you don't want him to start this "positive force" at 12, how about 14? 16? When exactly would you like to see him reaping the manifold benefits of this "positive force?"

And recall that this entry is about "medical" marijuana. Surely you want to give your kid "medicine," right, no matter how young he is. Yes?

Posted by: Bill Otis | Mar 27, 2014 4:09:12 PM

Michael R. Levine --

Don't feel dated. Under certain conditions, I still enjoy the original version of this: http://www.youtube.com/watch?v=rda6qVAR0Sg&feature=related

Posted by: Bill Otis | Mar 27, 2014 4:14:30 PM


This is an easy question, and again, I'm surprised you don't already know the answer to it - surely, it is the same answer I would give (and I suspect you would give) if asked why I wouldn't give my kids the car keys, a firearm, or a sixpack of beer. Marijuana is a wonderful thing, if used responsibly, and children are not capable of exercising the self-restraint or self-awareness necessary to use it responsibly. Just like driving, owning a weapon, drinking alcohol, and having sex are all wonderful things, if done responsibly, and yet we discourage their use by children, who are not yet capable of engaging in those activities safely and responsibly. I also think there's some decent science out there that marijuana might have a negative effect on the developing brain (much like alcohol might), and so to be on the safe side I wouldn't want my children to indulge until they were adults.

As for "[w]hen exactly" I would like my children to enjoy the positive benefits of marijuana, I think college is probably the age where people begin to learn how to exercise the necessary restraint and awareness. That seems to be society's general attitude toward when drinking becomes appropriate (despite what the law says), and I think it would make sense to treat marijuana the same way.

I recall that this entry is specifically about medicine, but your post arguing that marijuana "decreases ANY activity that might conceivably be productive" was not specifically about medicine, so neither was my response. But to answer your question, while I think marijuana as a recreational substance is something that should be denied to children, if my child had a serious medical condition that necessitated its use (like, God forbid, Dravet Syndrome), then yes, I would absolutely give him marijuana. More on that here, if you're interested: http://www.cnn.com/2013/08/07/health/charlotte-child-medical-marijuana/

But Bill, I would like to return to the main point, your argument that marijuana "decreases ANY activity that might conceivably be productive." Will you defend that argument or retract it? I suspect you cannot defend it, because you keep changing the subject.

Posted by: Curious | Mar 27, 2014 4:25:54 PM

Doug --

"Bill, in addition to being pleased that Curious has taken down your hyperbole..."

He hasn't taken down beans. He dodged the question, which you mistake for an answer.

"I am curious if you would become a support of medical marijuana reforms if (when?) we had reasonable evidence that such reforms may in fact reduce violent crime a bit."

Yikes. This one is really in orbit. Hey, tell ya what, I'm willing to concede here and now that legalizing "medical heroin" is likely to reduce crime, if for no other reason that the increased consumption that will result from easier access will produce more overdose deaths of people who'd been mugging to get the money for their habit.

Indeed, I'll go you one further: I'll also concede if we keep the ENTIRE POPULATION zapped on pot 24/7, there will be the biggest reduction in crime in the history of civilization. No one will do crime. Of course, no one will do anything else, either.

We know what reduces crime: prison. The evidence of the past 50 years is at this point beyond rational deniability. But prison is on your Bad List, although occasionally (very occasionally) people do clean up their act in there. Meanwhile, dope is on your Good List, not because you could (or do) think it's a wonderfully constructive thing for people to do, but (so far as I can see) because libertarian ideology commits you to drug legalization.

Could you tell me once more what the AMA thinks of the "benefits" of pot? Do lawyers know more than doctors about that?

Posted by: Bill Otis | Mar 27, 2014 4:32:40 PM

And to both Bill and Michael - don't worry, marijuana use is old and widespread enough for users to sometimes feel dated themselves as well. I, for example, enjoy the original version of this: https://www.youtube.com/watch?v=PN9n1bAahg4

Posted by: Curious | Mar 27, 2014 4:36:26 PM

"He hasn't taken down beans. He dodged the question, which you mistake for an answer."

Bill, I hope my response above answers your question, and I hope you will answer mine as well!

Posted by: Curious | Mar 27, 2014 4:39:50 PM

Curious --

You're getting a good deal of rhetorical mileage by repeating my words with a period at the end. But there wasn't a period at the end, not where you're putting it. What I actually said was, "...decreases ANY activity that might conceivably be productive, like diligent and focused work, for example."

The sentence has a different meaning when it's read with the seven words at the end that you deleted. That's why you deleted them.

I strongly suspect that the huge bulk of the world's great music was composed by people who were NOT zapped. I can't prove that, of course....any more than you can prove that it was composed by people who were.

Now one question for you (which you can answer because you keep your name concealed): Do you intentionally flout federal law, for no reason other than recreation, because you feel like obeying the law is for others?

Posted by: Bill Otis | Mar 27, 2014 4:48:32 PM

Don't know but I'd be amazed if Mr. Otis has ever had kids of his own and if so it's hard for me to even begin to imagine the type of sheltered life they must have endured during adolescence.

Posted by: Greg | Mar 27, 2014 4:50:07 PM

Greg --

"Don't know but I'd be amazed if Mr. Otis has ever had kids of his own and if so it's hard for me to even begin to imagine the type of sheltered life they must have endured during adolescence."

The anonymous guttersnipe Left, no longer content to go after my wife as a "kapo" now brings my kids (assuming I have some, which is none of your business) in for some bashing for the life they "must have endured."

That's enough, guys. Take your references to my family and go to hell.

Posted by: Bill Otis | Mar 27, 2014 4:55:48 PM


Thank you for your response. Unfortunately, you do not explain, and I confess I do not understand, how the extra seven words in your quotation give your argument a different meaning. I assure you I did not delete them in order to distort your position. Perhaps you can explain further?

I understand your general argument to be that marijuana decreases any conceivably productive activity. I believe you used the extra words that I deleted, referring to "diligent and focused work," in order to offer a specific example of such activity. I readily concede that marijuana decreases a person's ability to engage in diligent and focused work. However, I brought up creative inspiration as a specific counter-example to your general point, because I think it is a conceivably productive activity that marijuana increases, rather than decreases.

Please correct me if I misunderstood your argument. Or, if you like, please concede that marijuana does increase some activities that might conceivably be productive. I am interested to hear your response.

And yup, I bet you're right that the majority of the world's great music was composed by sober artists. But I am sure that I can prove that at least some of the great music (and art, and literature as well) was composed by pot smokers, and that their music was directly influenced by their marijuana use. Here, for example, is a great moment in music history: http://www.beatlesbible.com/1964/08/28/bob-dylan-turns-the-beatles-on-to-cannabis/

As to your last question, I certainly don't think that I am the only person entitled to flout federal marijuana law for recreational purposes - after all, it would be pretty silly of me to get upset at other people using marijuana if I am as well.

Posted by: Curious | Mar 27, 2014 5:07:00 PM

Greg, that's totally out of line and frankly stupid. It is simply beyond me why people spend their energy spewing poison on an internet message board, when there are so many better ways to devote one's attention.

Bill, I hope you will ignore the haters and continue our discussion. I appreciate your time.

Posted by: Curious | Mar 27, 2014 5:12:16 PM

"That's enough, guys. Take your references to my family and go to hell."

That was not meant as a personal family attack, such a thin skin when you choose to flaunt it. Life's experiences can have a huge effect on ones life and having kids is one of them. The comment meant to possibly explain why you seem to show little empathy in your writtings on this site. The life you have is the one you've made for yourself and comes across in your writings here as angry and sad.

Posted by: Greg | Mar 27, 2014 5:23:49 PM

The most crimogenic substance on earth is, of course, alcohol, with legal intoxication levels in half the murderers, half the murder victims, half the suicides, half the car crashes (now one third), likely most of the domestic dispute calls for the police.

Prohibition dropped consumption by only 50%, since it did not have public support. Yet, the Twenties were boom times, with low crime rates outside of bootlegging competition, and lower death rates by cirrhosis rates (occurring only in 10% of alcoholics, but a reliable correlate and marker of general alcohol consumption and addiction).

I support banning alcohol and tobacco, backed up by mass executions, lashings, etc. However, realistically, there is zero support for a ban, and zero chance it will ever re-occur. So I favor legalization of marijuana.

I would issue Adult Pleasure Licenses, and get Medieval with anyone supply a person who has lost his due to addiction. That leaves 98% of us alone to enjoy adult pleasures, and restricts those who are addicts.

Posted by: Supremacy Claus | Mar 27, 2014 6:00:17 PM

Greg, it seems to me that the angry and sad one is the person who trolls internet message boards launching personal attacks. I wish you hadn't derailed an interesting and productive conversation with your utterly pointless post.

Posted by: Curious | Mar 27, 2014 6:07:49 PM

One of the things I have never said here is that there are some admirable traits of the lawyer profession. One of them is a disciplined advocacy rhetoric, mostly aimed at persuasion and at compelling judges to rule in favor of a client.

Greg needs to tell us if he a working lawyer. If he is not, his remarks are the barkings of a dog behind a fence on the way somewhere. We keep walking. No big deal.

If he is a lawyer, they are a professional responsibility problem. He needs to apologize for them and to promise to take a course in advocacy. Imagine the reaction of a judge had he made them in a tribunal. The jury would take that judge reaction as a cue as to which way to decide the verdict. Case is over for his client, and a lawyer malpractice claim is not frivolous.

If Greg cannot control himself in the face of frustration in the traverse, he could help himself by getting evaluated and treated for his impulse problem.

Posted by: Supremacy Claus | Mar 27, 2014 6:38:45 PM

Here is an argument on the side of Bill.

There is a THC brain receptor. Why? No one knows what it does.

Say marijuana delivers THC to the receptor, and a great benefit in self medication is achieved, fewer seizures, less anxiety where nothing else works, better appetite after chemotherapy.

If the aim is beneficial self medication, one may get marinol prescribed. It is legal, from a pharmcy, and not a carcinogenic plant smoked deep into the lungs. Marinol is swallowed, has to cross many barriers and survive many removal mechanism before reaching the blood and brain, slowly, and over an hour after ingestion.

So all advocacy for legal marijuana smoking is hypocritical and pretextual, aimed at getting high, not at self-medication.

Another argument in Bill's favor. Amotivational syndrome as part of and during marijuana intoxication (not a separate disorder). Imagine a quarter of the population choosing that as a career.

Posted by: Supremacy Claus | Mar 27, 2014 6:48:32 PM

Marijuana turns out to have a safety profile comparable to that of broccoli.

The questions of social impact and public health ride fundamentally on whether its legalization will lead to increased or decreased use of alcohol, opiates, and benzodiazepines. All of which show dramatic dangers of addiction and anti-social behavior not seen with pot.

A representative case is the growing problem of pharmaceutical and street opiates, which seems to be driven by poorly-managed pain relief. The spectrum of pain cases range from those who can manage with NSAIDs (like Motrin) all the way up to those with such severe pain that massive amounts of opiates are required. Somewhere in the middle are a group who might, with access to appropriate strains of marijuana, avoid starting down the opiate route. From what I can see the advantage to this group, as well as the overall public health improvement, would be immense.

Posted by: Boffin | Mar 27, 2014 8:44:46 PM

lord I skip this thread for a couple of days and suddenly we're taking pot shots at family again.

sorry bill.

Posted by: rodsmith | Mar 29, 2014 10:53:09 PM

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