By Alex H. Kral, Jamie L. Humphrey, Clyde Schwab, Barrot H. Lambdin, Bradley Ray,

Importance Opioid-involved overdose mortality has been on the rise for 2 decades in the US, exacerbated by an unregulated drug supply that is unpredictable and has increasingly contained highly potent fentanyl analogs starting a decade ago.

Objective To determine whether there is a geospatial association between law enforcement drug seizures and opioid-involved overdose mortality in San Francisco.

Design, Setting, and Participants This cross-sectional study used location- and time-stamped overdose mortality data from the Office of the Chief Medical Examiner and publicly available crime data from the San Francisco Police Department between 2020 and 2023 to assess whether location and time of law enforcement drug seizures were associated with subsequent opioid-involved overdose mortality. Data were analyzed from January 2020 to September 2023.

Exposures Time-stamped locations of law enforcement drug seizures involving a drug distribution charge.

Main Outcomes and Measures The primary outcomes were the time and location of (1) overdose mortality involving any opioid and (2) overdose mortality involving fentanyl or any fentanyl analog. The relative risk (RR) and 95% CIs for endemic and epidemic factors were calculated.

Results There were 2653 drug seizure crime events that involved any drug distribution charge and 1833 overdose deaths that tested positive for any opioid or synthetic opioid, including heroin and fentanyl analogs. Within the surrounding 100 meters, law enforcement drug seizures were associated with increase risk of fatal opioid-involved overdoses the day following the drug seizure event (RR, 1.74; 95% CI, 1.06-2.83; P = .03) and elevated risk persisted for 7 days (2 days: RR, 1.55;95% CI, 1.09-2.21; P = .02; 3 days: RR, 1.45; 95% CI, 1.08-1.93; P = .01; 7 days: RR, 1.27; 95% CI, 1.11-1.46; P = .001). Similar statistically significant spatiotemporal patterns were observed in the 250- and 500-meter spatial bandwidths. Within each space-time kernel, the strength of the association, all of which were statistically significant, dissipated the further away in time and distance from the law enforcement drug seizure event.

Conclusions and Relevance The findings of this cross-sectional study suggest that the enforcement of drug distribution laws to increase public safety for residents in San Francisco may be having an unintended negative consequence of increasing opioid overdose mortality. To reduce overdose mortality, it may be better to focus on evidence-based health policies and interventions.

JAMA Netw Open. 2025, 11p.

By Roderic Broadhurst, Matthew Ball, Chuxuan Jiang, Joy Wang and Harshit Trivedi

Opioids, including the highly potent synthetic opioids fentanyl and carfentanil, are commonly sold on illicit cryptomarkets or Tor darknet markets. Data collected throughout 2019 from 12 large darknet markets that sold opioids enabled observation of the impact of law enforcement seizures and voluntary or scam market closures on the availability of fentanyl and other opioids.

Trends in opioid and fentanyl availability before and after law enforcement interventions indicate whether market operators and sellers are deterred and whether market closures lead to displacement, dispersal or substitution. Evidence of all of these outcomes was present in both descriptive and trend analyses, although most effects were short lived. Market closures, especially law enforcement seizures, reduced the availability of opioids, in particular fentanyl, as well as increasing prices and displacing vendors to other markets. Market closures also led vendors to substitute fentanyl for other opioids or other illicit drugs.

Research Report no. 18. Canberra: Australian Institute of Criminology, 2021. 73p.

By Alex Brill | Scott Ganz

Recent data show a small decline in opioid-related mortality following a decade during which opioid-related mortality more than doubled to nearly 53,000 in 2018. However, the aggregate statistics mask important spatial and temporal trends in the data. This report estimates nationwide, regional, and county-level economic costs associated with the opioid crisis. The data show that, despite recent nationwide per capita opioid-related cost declines, the impact of the crisis continues to be felt across large swaths of the Northeast, Midwest, and South. We also find that opioid-related mortality tends to diffuse among nearby counties, with the local diffusion rate from illegal opioids—which are the primary cause in the current wave of the crisis—exceeding the rate from prescription opioids, which were the primary cause in earlier waves. The combination of lower aggregate mortality and faster diffusion among nearby counties points to a changed spatial distribution of economic costs as the opioid crisis evolves.

Washington DC: American Enterprise Institute, 2020.