Seizure-to-market ratios and the resilience of the drug markets in France (2010-2023).

BACKGROUND

Drug seizures are widely used as indicators of law enforcement performance, yet their ability to disrupt drug markets remains unclear. Recent evidence highlights the lack of rigorous empirical research assessing whether seizures reduce drug availability, crime, or harms. This study compares estimated quantities consumed in France with official seizure volumes to evaluate the relative scale and policy relevance of drug seizures.

METHODS

We used a demand-side, bottom-up approach to estimate consumption volumes for cannabis, cocaine, heroin, MDMA/ecstasy, and amphetamines for 2010, 2017, and 2023. These estimates were derived from representative population surveys and consumption indicators. Seizure volumes were drawn from national statistics. Seizure-to-market ratios were computed for each substance and year.

RESULTS

In 2023, estimated consumption reached approximately 400 tonnes of cannabis, 47 tonnes of cocaine, 8 tonnes of heroin, 65 million MDMA/ecstasy tablets, and 5.6 tonnes of amphetamines. Seizure-to-market ratios show stable proportions for cannabis (20-30%) and heroin (13-16%), low ratios for MDMA/ecstasy (3-20%), and unusually high ratios for cocaine in 2017 (46-122%), reflecting France's role as an interception point for Europe-bound trafficking. Despite these seizure volumes, retail prices remained stable or declined, while purity and inflation were rising over the same period.

CONCLUSION

The convergence of our estimated seizure ratios with contextual market indicators (stable or falling prices, increasing purity, and inflation) suggests that drug markets remained resilient and that seizures had limited impact on availability. These findings underscore the need for more comprehensive indicators to evaluate supply-side drug policies.