This month, two reports came out of Colorado on the impact of marijuana legalization in the state. One, funded by the federal government, which opposes legalization, found that the impact is adverse, with an increase in drug use, emergency room visits, exposure to infants and more. The other, funded by the state, which obviously supports legalization, noted that past-month use by high school seniors did not go up from 2011 to 2013 — it’s still about one in four students.

The Colorado marijuana impact report issued last week by the Rocky Mountain High Intensity Drug Trafficking Area (HIDTA) program shows a 100 percent increase in traffic fatalities involving drivers testing positive for marijuana from 2007 to 2012. The report also found a 57-percent increase in marijuana-related emergency room visits from 2011 to 2013, an 82-percent increase in hospitalizations related to marijuana from 2008 to 2013, and a 268 percent increase in marijuana-related exposures to children ages 0 to 5 from the 2006–2009 time period and the 2010–2014 time period. The HIDTA program is run by the federal Office of National Drug Control Policy.

However, on August 8, the state Department of Public Health and Environment issued its 2013 Healthy Kids Colorado Survey showing that from 2011 to 2013, past-30-day marijuana use among high school seniors dropped from 22 percent to 20 percent. Pro-legalization advocates — which include the state of Colorado — argued that the survey shows that legalization is not having a harmful effect on underage use, which is illegal in Colorado. The state is still planning a prevention campaign to warn young people about the damage marijuana could inflict on their brains, according to the state announcement.

The Colorado survey did not refer to daily use by high school seniors, which was found to be increasing by the Monitoring the Future study conducted by the National Institute on Drug Abuse (see ADAW, December 23, 2013). For the past two surveys, 6.5 percent of high school seniors across the country reported smoking marijuana daily — the most dangerous type of use. Researchers with the Monitoring the Future study expect the perception of risk to be lowest in states where marijuana is legal. The lower the perception of risk, the higher the use.

For the HIDTA report, go to

For the state survey announcement, go to