If Legalizing Marijuana Was Supposed To Cause More Crime, It's Not Doing A Very Good Job

When Colorado legalized weed more than a year ago, opponents of the move warned that crime would rise. But half a year after the first sales of recreational marijuana began, the state's biggest city has yet to see an increase in criminal activity.

During the first six months of 2014, violent crime in the city and county of Denver was down 3 percent from the same period in 2013, according to the most recent available data . Three of the four main categories of violent crime that are tracked in the data -- homicide, sexual assault and robbery -- are all down from the same six-month stretch last year. Aggravated assault, the fourth category, is up 2.2 percent.

Burglaries and robberies at the city's dispensaries of medical and/or recreational marijuana are on track to hit a three-year low , according to a separate report from Denver's Department of Safety, first reported by The Denver Post.

Overall, property crime in the city is down by more than 11 percent from the same six-month period of 2013.

Of course, Denver is just one city with legal weed. But as the first, albeit no longer only , large municipality in the U.S. with legal retail marijuana shops, Denver seems a worthy example. The state's second-largest city, Colorado Springs, banned the retail shops in 2013 as did more than two dozen other cities . While Washington state has also legalized recreational weed, sales began just this month and only a handful of shops have opened there.

Correlation does not imply causation, regardless of which way the crime data move, and after just six months, it may be too early to identify any strong social trends. But evidence of a crime wave simply has not materialized -- despite numerous dire warnings prior to legalization.

In 2012, before Amendment 64 legalized marijuana in Colorado for recreational sale and use, multiple members of the state's law enforcement community warned that the measure would bring "harmful" consequences .

"Expect more crime, more kids using marijuana and pot for sale everywhere," Douglas County Sheriff David Weaver said in 2012 . "I think our entire state will pay the price."

Crime rates may not have gone up, but revenue is soaring. Since January, Colorado's dispensaries have sold about $90 million worth of retail cannabis . The state has collected about $35 million in taxes, licenses and fees from both the recreational and medical marijuana markets, according to the Colorado Department of Revenue's latest tax data . Colorado legalized medical marijuana in 2000.

Denver's crime statistics during the first six months of retail marijuana align with a report recently published in the peer-reviewed journal PLOS ONE showing that legalizing medical marijuana causes no increase in crime and may in fact be accompanied by a decrease in some violent crime, including homicide.

Just Colorado and Washington state permit retail marijuana. To date, 23 states and the District of Columbia have legalized marijuana for medical use, and about a dozen others are considering legalization in some form in the next few years.