A worker inspects a marijuana plant at a grow house in Denver, on Thursday, Nov. 8, 2012. Marijuana legalization votes this week in Colorado and Washington state don't just set up an epic state-federal showdown on drug law for residents. The measures also opens the door for marijuana tourism. (AP Photo/Ed Andrieski)

How goes Colorado's experience with legal marijuana? Spend some time on social media or on numerous blogs and you'll read headlines like "Revenue Up, Crime Down!" or "Youth Use Declining After Legalization." In this short blog series, I will tackle different topics that have been the subject of myth and misinformation.

First up: crime.

Lately legalization advocates have been cheering numbers that show a decline in crime. There are literally hundreds of articles that have been written with this narrative. But an honest look at the statistics shows an increase -- not decrease -- in Denver crime rates.

Crime is tracked through two reporting mechanisms: the National Incident Based Reporting System (NIBRS), which examines about 35 types of crime, and the FBI Uniform Crime Reports (UCR). The FBI UCR only captures about 50 percent of all crimes in Denver, so the NIBRS is generally regarded as more credible. The Denver Police Department (DPD) uses NIBRS categories to examine an array of crime statistics, since it is the more detailed and comprehensive source of numbers.

The Denver Police statistics show that summing across all crime types -- about 35 in all -- the crime rate is up almost 7 percent compared with the same period last year. Interestingly, crimes such as public drunkenness are up 237 percent, and drug violations are up 20 percent.

So why are advocates claiming a crime drop? Easy: They blended part of the FBI data with part of the DPD/NIBRS data to cook up numbers they wished to see. When one picks the Part I data from UCR and uses DPD/NIBRS property-crime numbers only while studiously avoiding the DPD/NIBRS data on all other crimes, one can indeed manufacture the appearance of a decline. As one can see here, even when using the FBI UCR numbers -- in their entirety -- crime has risen.

A report commissioned by the National Association of Drug Court Professionals puts it nicely:

When a closer look at the data is undertaken, a different picture -- something other than "crime is down" -- appears to emerge. ... [L]egalization proponents should not infer causality regarding the downward trend observable when isolating just the UCR's Part I crime index.

When I asked the president of the Colorado Drug Investigators Association, Ernie Martinez, about these statistics, he urged me to look at the crimes that have been happening in connection to marijuana -- even after legalization:

Across the Front Range, we are experiencing more and more butane explosions due to hash extraction methods, calls for service on strong smells, and calls to ER's on adverse effects after either ingestion or smoked use. Black-market continues to exist unabated, availability of black market marijuana is ever present and cheaper than legalized MJ. Medical marijuana registrants continue to rise due to many factors such as more quantity allowed and more plants allowed, all due to Physician recommendations.

So if crime is up, can we blame legal pot? We do not know whether legalization has anything to do with it. But we do know that reputable news organizations should stop relying on the Big Marijuana lobby for statistics. They wouldn't blindly trust coal-industry statistics on the environmental effects of strip mining, and they should bring similar skepticism to propaganda claims disseminated by this new industry.