Background: In 2023, recreational cannabis use became legal in private residences for adults ages 21+ in Maryland. However, because cannabis remains a Schedule I drug under federal law, colleges and universities receiving federal funds must continue to prohibit the use, possession, and distribution of cannabis on campus and at campus-sponsored events. This study examines trends in awareness of cannabis use laws among Maryland college students.

Method: Data come from the 2023, 2024, and 2025 waves of an online, cross-sectional survey of undergraduate students at 18 colleges in Maryland (ns 2,721-3,976 per year; 64% female, 42% non-Hispanic white). Items assessed knowledge of the minimum legal age (MLA) for cannabis use and legality of cannabis use in seven location types (e.g., in bars/restaurants, at campus-sponsored events). Regression models were developed to examine trends in knowledge from 2023 (four months pre-legalization) to 2025 (20 months post-legalization) overall and by demographic characteristics.

Results: Knowledge of cannabis laws increased from 2023 to 2024 but was stable into 2025. This trend did not differ by gender, race, or age, although white students and students ages 21+ were more likely than others to know the laws across all years. In 2025, 68% of students identified the correct MLA (54% in 2023), but only 12% correctly identified the legality of use in all seven locations (8% in 2023). The lowest percentages of correct responses were for public places off campus (not legal; 48% answered correctly) and in bars/restaurants (not legal; 56% answered correctly). The majority knew that cannabis use is not allowed on campus or at campus-sponsored events off campus (78% and 71% correct, respectively).

Conclusion: These findings indicate that education about cannabis laws is needed for college students, as is further research on the interplay of knowledge, enforcement, and use.