In 2021, Oregon became the first state in the United States to decriminalise the possession of small amounts of all drugs for personal use with the implementation of Measure 110. This policy shift aimed to reduce the harms associated with drug use, such as overdose fatalities, by redirecting resources towards addiction treatment and recovery programs. However, the rapid spread of fentanyl, a potent synthetic opioid, in Oregon’s unregulated drug market has raised questions about the effectiveness of such decriminalisation policies on reducing drug-induced mortality. This cohort study investigates the association between drug decriminalisation, the spread of fentanyl, and fatal overdoses in Oregon.

Study Methodology

The study utilised a matrix completion synthetic control method to assess the changes in fatal overdose rates in Oregon post-decriminalisation, accounting for the timing of fentanyl’s spread. It compared the trends in Oregon against a synthetic control group composed of the remaining 48 states and Washington, DC, which did not decriminalise drugs. Data was sourced from the National Forensic Laboratory Information System (NFLIS) to track fentanyl’s presence and from the CDC for mortality rates, covering January 1, 2008, to December 31, 2022. The study analysed the association between fentanyl exposure and overdose mortality through various statistical models, incorporating state and time fixed effects.

Key Findings

• Fentanyl Spread: The rapid spread of fentanyl was observed in the US between 2014 and 2021, with Oregon experiencing significant saturation in early 2021, coinciding with the enactment of Measure 110.
• Overdose Mortality Rates: The study found a positive association between fentanyl saturation and overdose mortality rates across states. In Oregon, the increased presence of fentanyl was linked to higher overdose death rates.
• Impact of Decriminalisation: Initially, decriminalisation appeared to correlate with increased overdose deaths; however, after adjusting for fentanyl exposure, no direct association between decriminalisation and higher mortality rates was observed.
• Regional Patterns: The spread and impact of fentanyl varied by region, with western states like Oregon experiencing later saturation compared to eastern states.

Implications for Public Health

The findings suggest that the rise in overdose deaths in Oregon post-decriminalisation is more closely related to the fentanyl crisis than to the policy of decriminalisation itself. This underscores the critical need for public health interventions that address the challenges posed by the infiltration of fentanyl into the drug market. While decriminalisation holds promise for reducing the stigma and barriers to treatment for drug users, its success heavily depends on robust support systems and timely implementation of treatment services.

Study Limitations and Future Research

The study acknowledges several limitations, including the use of proxy measures for fentanyl presence and the inherent challenges of modelling complex policy impacts. The potential non-differential undercounting in mortality data and the variability in data reporting across states could affect the findings. Future research should explore the long-term effects of decriminalisation policies, especially in the context of evolving drug markets dominated by synthetic opioids like fentanyl.

An accurate assessment of decriminalisation efforts requires comprehensive evaluations that consider the dynamic nature of drug supply changes and their broader social implications. Continued study into effective intervention strategies and policy adjustments is essential as states navigate the complexities of drug decriminalisation and its health outcomes.

Source: JAMA Network