The study found that — even after taking into account other factors — nearly one fewer person per month died of an opioid overdose in Colorado after the start of legal cannabis sales in 2014 compared to before. The paper’s authors stop short of saying that legalization caused the reversal, instead saying that legalization was “associated” with a decline in opioid deaths. The authors also caution that the study looks only at a small sliver in time because legalization is still relatively new.
“These initial results clearly show that continuing research is warranted as data become available, involving longer follow-ups and additional states that have legalized recreational cannabis,” the study’s authors write.
Officials in Colorado met the study with skepticism Monday.
Dr. Larry Wolk, the executive director of the Colorado Department of Public Health and Environment, said it is too soon to draw sweeping conclusions about legalization’s impact.
“It just hasn’t been in place long enough,” Wolk said. “Anything that does get published at this point should be considered preliminary data.”
