Study of Over 35,000 Finds Germany’s Marijuana Legalization Did Not Increase Annual or Heavy Cannabis Use
- A study of nearly 36,000 people in Germany found no increase in past-year cannabis use or heavy consumption during the first two years after marijuana legalization.
- The research, using 23 surveys from 2022 to 2026, showed stable rates of marijuana use and heavy use (daily or almost daily) before and after the Cannabis Act took effect in April 2024.
- No statistically significant changes in cannabis use were observed across different age groups (14-24 and 25-64) or by gender, with sensitivity analyses confirming stable consumption trends.
- Germany’s law permits adults to possess limited amounts of marijuana and cultivate up to three plants, but does not yet have a commercial retail market; researchers recommend ongoing monitoring to assess longer-term effects.
A large new study examining nearly 36,000 people in Germany found no evidence that the country’s legalization of marijuana led to an increase in either past-year cannabis use or heavy consumption during the first two years following the reform.
The study, published this month in the International Journal of Drug Policy, examined 35,957 respondents between the ages of 14 and 64 using 23 repeated population surveys conducted from April and May 2022 through March and April 2026.
Germany’s Cannabis Act took effect April 1, 2024, allowing adults to legally possess and cultivate marijuana. Researchers analyzed roughly two years of data from before the change and two years after it took effect.
Among all respondents, 2,302, or 6.4%, reported using marijuana at least once during the previous 12 months.
Researchers found that the prevalence of past-year marijuana use remained largely stable following legalization. The proportion of past-year consumers who reported daily or almost daily use — classified by researchers as heavy use — also remained largely unchanged.
None of the statistical measures examining whether the trajectory of marijuana use changed following implementation of the law reached statistical significance. The same was true when researchers separately examined participants by gender and by age, comparing those ages 14 to 24 with those ages 25 to 64.
Sensitivity analyses using alternative dates for when a potential legalization-related change might have occurred also supported the finding that consumption trends remained stable.
The researchers concluded that Germany’s 2024 marijuana reform “was not associated with changes in 12-month use prevalence or heavy use early (two years) after implementation.”
The authors cautioned that the findings cover only the first two years following the law change and said continued monitoring is warranted because longer-term effects could emerge later.
Germany’s law allows adults to possess up to 25 grams of marijuana in public and up to 50 grams at home, while permitting the cultivation of up to three marijuana plants per adult. The country has also established nonprofit cultivation associations through which members can obtain marijuana, although it has not implemented a traditional nationwide commercial retail market.