Jonathan Caulkins is Stever University Professor of operations research and public policy at Carnegie Mellon University. Peter Reuter is distinguished university professor in the School of Public Policy and department of criminology at the University of Maryland.
Ever since opioid deaths suddenly peaked and began to decline in summer 2023, plunging by nearly half over the next two years, experts have been puzzling over why this blessed event occurred. Was it improved public health policies? Increased enforcement? The previous deaths of so many fentanyl users? Or something else?
In an article published Thursday in Science, we make a case, along with several colleagues, for one major contributor: a reduction in the supply of fentanyl, which was associated with 90 percent of all fatal opioid overdoses in 2022.
Three lines of evidence point in this direction.
First, multiple indicators of fentanyl supply turned downward at the same time deaths did. Notably, the purity of fentanyl powder fell in the second half of 2023 after rising steadily for several years; that meant consumers were getting less fentanyl — and thus running a lower risk of death — from any given purchase. The amount of pure fentanyl in counterfeit pills also fell at that time, as did the number and weight of drug seizures, despite intense federal enforcement.