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No, marijuana has not caused a "sharp increase" in crime in US states which have legalized it

Former New York Times reporter Alex Berenson claims marijuana legalization appears to lead to “sharp increases” in murders and aggravated assaults.
However, several studies have found no apparent link between relaxing legal restrictions on cannabis and violent crime, Reason writes.
“We can’t conclude that marijuana legalization increases violence,” University of Oregon economist Benjamin Hansen says Hansen says. “The homicide rates in Colorado and Washington were actually below what the data predicted they would have been given the trends in homicides from 2000-2012.”
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