Analysis shows no change in US crime from medical marijuana legalisation

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Victoria University of Wellington research shows there has been almost no change to the level of crime in the United States since the legalisation of medical marijuana.

The research, led by Dr. Luke Chu from the School of Economics and Finance and former student Wilbur Townsend, studied national crime rates as well as rates in individual states that have passed laws, and found minor effects.

The exception was California, where violent and property crime reduced by 20 percent between 1996—when medical marijuana was legalised there—and 2013.

The researchers compared before and after data on specific crimes including murder, rape, robbery, aggravated assault, burglary, larceny and motor vehicle theft between states with and without legalised marijuana. Nearly all of the estimated changes in crime rates are close to zero at national and state levels.

California's 20 percent reduction in crime could be due to a range of factors, says Dr. Chu.

"There's no definitive answer as to why. California is a relatively liberal state and was the first U.S. state to legalise medical marijuana.

"Other recent studies have shown that cause an increase in heavy use, but a reduction in other acts including drunk driving, heroin usage and opioid addiction."

Dr. Chu says the findings are comparable to a New Zealand context. "I believe we would be unlikely to see a large surge in crime if it were legalised here."

Previous studies have explored the topic, but with conflicting findings, says Dr. Chu. This study is the first of its kind to examine state-specific effects.

"In addition to traditional regression analysis, we used a technique called synthetic control method to analyse the data. This allows us to take into account pre-law differences in trends without making extra assumptions."

The study, led by Wilbur as part of his Honours thesis, was recently published in the Journal of Economic Behavior & Organization.


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Aug 22, 2018
Among other things, leaving aside such points as the definitions of crimes, if everyone took arsenic, afterward, all rates of all crimes would go to zero. That doesn't make it right. If everyone lobotomized themselves, afterward, there would be a steep drop in crimes committed. If drug use makes someone so reckless, they kill themselves by accident, will that be recorded as a crime? It's not necessarily ascertained the effect that easy drug access has on things like homelessness. But destroying one's life isn't necessarily listed as a crime. But that doesn't make it right.
A point, too, that so many ignore. Making marijuana easily accessible is said to lower the use of things like opioids. In general, to satisfy someone, an alternative drug must have at least as potent an effect as the drug they are replacing. This indicates that, in fact, marijuana is far, far more powerful than those promoting marijuana addiction are willing to admit.

Aug 22, 2018
Well it's easy to see that julian is a strict adherent of the Prohibitionist's Motto:
"Never let the facts get in the way of disseminating a Then effective piece of hysterical rhetoric"


Aug 23, 2018
In general, to satisfy someone, an alternative drug must have at least as potent an effect as the drug they are replacing.


Nonsense, it just has to be more pleasant, or more available, or more acceptable. When weed was illegal I drank more alcohol, a considerably stronger and more dangerous drug with unpleasant side effects (including hangovers) because it was what was available. Now I rarely drink at all.

Aug 28, 2018
Without the use of any mind-altering substances whatsoever, julianpenrod believes in chemtrails and the new world order, as well as being a rabid racist and misogynist, so I find it amusing that you are attempting to have a rational discussion with him. It won't work. Your best option is "Ignore user" or give his posts a 1 star and move on without replying.

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