Published in full in the Washington Post.
There's a body of research showing that painkiller abuse and overdose are lower in states with medical marijuana laws. These studies have generally assumed that when medical marijuana is available, pain patients are increasingly choosing pot over powerful and deadly prescription narcotics. But that's always been just an assumption.
Now a new study, released in the journal Health Affairs, validates these findings by providing clear evidence of a missing link in the causal chain running from medical marijuana to falling overdoses. . .