More Pot, Less Crime: Medical Marijuana States See Drops in Assaults and Homicides


Sonya Yruel/Drug Policy Alliance

A study published by the online journal PLOS One yesterday finds that adoption of medical marijuana laws is not associated with an increase in crime and may even result in fewer assaults and homicides. Robert G. Morris and three other University of Texas at Dallas criminologists looked at trends in homicide, rape, robbery, assault, burglary, larceny, and auto theft in the 11 states that legalized marijuana for medical use between 1990 and 2006. While crime fell nationwide during this period, it fell more sharply in the medical marijuana states, even after the researchers adjusted for various other differences between states. Morris and his colleagues suggest that the substitution of marijuana for alcohol could explain this result, although they caution that the extra reduction in crime might be due to a confounding variable they did not consider.

What seems clear is that these crime data do not support the notion that making marijuana more readily available drives up crime rates, whether because of marijuana's effect on behavior (including use of other drugs) or because of robberies associated with cash-heavy cannabusinesses:

The central finding gleaned from the present study was that MML [medical marijuana legislation] is not predictive of higher crime rates and may be related to reductions in rates of homicide and assault. Interestingly, robbery and burglary rates were unaffected by medicinal marijuana legislation, which runs counter to the claim that dispensaries and grow houses lead to an increase in victimization due to the opportunity structures linked to the amount of drugs and cash that are present….This is in line with prior research suggesting that medical marijuana dispensaries may actually reduce crime in the immediate vicinity.

How relevant is research on medical marijuana laws to the debate about broader forms of legalization? Highly relevant, if you take the view that medical marijuana is mostly a cover for recreational use, as prohibitionists tend to argue. In truth, the legal regimes governing the medical use of marijuana range from very strict (such as New Jersey's) to very loose (such as California's). But it is fair to say that a lot of people with doctor's recommendations in the looser states are recreational users in disguise. It therefore makes sense that legalizing medical marijuana would be accompanied by a decline in drinking, as Morris et al. suggest. Such a substitution effect may also explain why medical marijuana laws are associated with a decline in traffic fatalities.

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  1. Just wait until the caravan of minivans from Sunny Minnesota full of desperate soccer moms with their epileptic kids show up!

    Those scofflaws are worse than the gang in Road Warrior. They won’t let you walk away. They’ll take your grass and kill you.

  2. I was gonna rob a bank
    But then I got high
    I was gonna rob a bank
    But then I got high
    I listened to Pink Floyd instead and I know why
    Because I got high
    Because I got high
    Because I got high

    1. I was gonna kill my lover
      But then I got high
      I was gonna make her live over
      But then I got high
      Instead I watched Cheech and Chong, and I know why
      Because I got high
      Because I got high
      Because I got high

      1. I was gonna shoot up a school
        But then I got high
        I was gonna waste all those fools
        But then I got high
        Now I love everybody and I know why
        Because I got high
        Because I got high
        Because I got high

        1. +1 slow clap.

          1. Unlike penicillin-resistant superclap.

  3. A study published by the online journal PLOS One yesterday finds that adoption of medical marijuana laws is not associated with an increase in crime and may even result in fewer assaults and homicides.

    And everything just tastes better.

    I can’t see much crime from people too broke to buy a J, so I’m going with the stoner mellow.

  4. This should offset the increase in crime caused by global warming.

    1. We call it climate change now, and the preferred term is “aggression” so that it can include actions perceived as being hurtful.

  5. I got tangled up in a pro/con MJ legalization discussion recently. I haven’t engaged in that before. I am shocked at how craven and sadistic the drug warrior crowd is. Absolutely appalling.

    One even claimed that children, suffering excruciating pain and misery from cancer treatment, should just ‘man-up’ and bear the pain rather than have their lives ruined by MJ. How do you even respond to something like that?

    1. Homocides and assaults would be declining faster if not for legalizing marijuana. Why do you love criminals, Suthen?

      1. This is a good point. If not for pot, we’d basically be in the Garden of Eden pre-apple eating days. Also, pot makes you lazy, which is why the violence rate has gone down. It’s all of those things and more.

        A couple weeks ago at a Lent service my pastor warned, and it sounds like I’m making this up but I promise I’m not, about a political party that, get this, says you can do whatever you want so long as you don’t harm anyone else. His two examples were marijuana and prostitution. Apparently, because we don’t want the state making them illegal, we support them. It’s frustrating because he’s a compassionate guy and his sermon was about not labeling people according to their sin, yet he can’t seem to separate society and state.

        I’d been thinking about removing the Gary Johnson bumper sticker, but I’ll be keeping it on now.

        1. “…. he’s a compassionate guy…”

          I am skeptical.

          1. Catholics have their own dictionary.

    2. I guarantee you, if you told them a story about how your grandfather cut his foot on glass, took a shot of whiskey, and sewed himself up, they’d give their nod of approval and talk about the days when men were men. It’s like pain is a sign of hardness, as is booze. I can’t tell you how many times I’ve heard people boast about how so-and-so lived to be 90 while eating a steak a day and having a whiskey at 4 and a double at 8 with the news. It’s as if what they really miss is the 50’s version of manhood, whatever that entails. There are some great self-sufficient aspects of that era, but drug prohibition isn’t one of them.

  6. It’s also possible that having the police spend less of their time on bullshit possession crimes means that they can spend more on real crimes.

    1. Is there money in that for them?

      1. Once they lay off the Narco Squad and the Vice unit.

      2. No, and they won’t be able to seize, keep and/or sell your property without due process.

  7. Did they take into account the possibility (read: logical necessity) that crime would go down BECAUSE MJ was legally available without considering alcohol?

    One of the best things about “Breaking Bad” was that it showed what was necessary to succeed in drug trafficking. The main character wasn’t “bad”, but he kept getting into worse situations simply because he was breaking a law. He needed to ensure that others wouldn’t rob his business or kill him. He had to commit acts of violence simply because he couldn’t get the state to prevent acts of violence against him. This is a good “thought experiment” and has likely played out throughout the country ever since someone decided to ban something.

    I would be willing to bet that most violent crime is caused by BANNING drugs, not by the drug users themselves.

    (If this is “old hat” and you all knew this already, I apologize for wasting your time.)

  8. Not wasted time. Except for one small quibble* this needs saying again and again until people start listening.

    *This is a good “thought experiment” and has likely played out throughout the country human civilization ever since someone decided to ban something.

    I know of no government in the history of the world that has successfully shut down a black market with use of force.

  9. But. . . . Will the old illegal dealers look for a new source of revenue.? Meth? Coke? Horse? A bit of dip in crime a trend does not make.

    1. What in the world makes people think that their is potential revenue being unexploited by criminals? Do you think it’s amotivational syndrome caused by being in the general vicinity of cannabis? Perhaps you think that criminals aren’t greedy, that their motto is take what they need and leave the rest?

      Of course one of the major points you’re missing is that the purveyors of hysterical rhetoric predicted that crime would skyrocket if medicinal cannabis patient protection laws were adopted and the statistics do prove that they were wrong, wrong, wrong, again.

      Ockham’s Razor says that it’s your inability to accept that you were played for a chump by the hysterical rhetoric. What the heck does it take to convince you? In 16 years of the Compassionate
      Use Act California’s crime rate has fallen 38.903%

      Same time frame the nationwide crime rate is down 36.196%

      What the heck does it take to get you people to admit that you’re wrong? Obviously the facts are irrelevant.

  10. It could be as simple as the fact that they went from busting heads to not busting heads.

  11. It is forgivable for the sheltered people of this world to not understand weed is the great demotivator.
    Potheads may commit less crime, but they also do a lot less of everything else that requires energy or deep thought.
    This is not a net plus by any calculus.

    1. There is no science to prove your point … actually quite the opposite. Your old stereotype of a lazy pothead is not the reality. Most pot smokers are highly successful and some even become president.

    2. There’s yet another la-la land fantasy. ConstitutionFirst doesn’t seem to have noticed the number of States in which we’ve gotten the laws changed, and done so in the face of an intransigent Federal government with $trillions of borrowed resources to squander in their quest for the continue embrace of the proven, epic failure of public policy called prohibition.

      The only logical conclusion of why people don’t admit that they’re wrong in the the face of carloads and carloads of evidence that says that they are wrong is that they would rather be wrong than admit it. Or is it also the fact that you’d have to admit that you were played for a chump by professional confidence artists as well as admit that you’re wrong, wrong, wrong?

    3. Yea, that’s crap. Lazy people who smoke pot are still lazy, motivated people who smoke pot are still motivated. I know a lot of motivated people, dedicated to and very good at their jobs who smoke. Since I don’t hang out with lazy people I don’t know any, personally, that smoke and are lazy.

  12. Here that sound? It is the popping of the fear mongering balloon.

  13. Funny how I’ve read where someone’s son, or a son of their friend smokes pot and is lazy and unmotivated. They go on to try to use this as proof that it should stay illegal. I commented ‘huh’? How does prohibition help the already lazy kid from getting the pot they are already smoking. What it does do is turn them into criminals, and if they get caught, almost impossible to get a good job when they do turn their life around and stop being lazy.

    Prohibition stifles speech about the pros and cons of use. It shuts down and real debate.

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