Four years after implementation, the majority of California cannabis users lacked knowledge of specific Prop 64 regulations, with only 49% knowing possession rules and 30% understanding gifting laws.
Public health educators, drug policy researchers, state cannabis regulators
Only 30% of users knew cannabis gifting rules
What the researchers found
Among 4,020 current cannabis users demographically matched to the 2020 California census, 71% described themselves as somewhat or very familiar with Prop 64, yet awareness of specific regulations was low: 49% knew possession rules, 41% knew transportation rules, and only 30% understood gifting regulations. Only half of current users felt Prop 64 made cannabis products and acquisition safer, and just 30% believed cannabis should be legal in more public places.
Why it matters
If most cannabis users do not know the rules governing possession, transportation, and gifting, they may unknowingly violate laws. This gap between perceived familiarity and actual knowledge suggests legalization rollouts need more effective public education.
The numbers in context
n=5,178 total (4,020 current users, 523 former, 635 non-users); 71% self-reported familiarity; 49% knew possession rules; 41% knew transportation rules; 30% knew gifting rules; 30% supported more public use; 50% felt legalization made products safer
How the study worked
Population-matched questionnaire completed by 4,020 current cannabis users, 523 former users, and 635 non-users selected from an initial pool matched to the 2020 California census. Chi-squared tests and nominal logistic multivariate analysis assessed knowledge and attitudes by demographics and cannabis use factors.
What this study cannot tell us
Cross-sectional survey cannot track how knowledge changes over time. Self-reported familiarity may not align with tested knowledge. Online panel recruitment may not fully represent all California demographics.
How to read the evidence
Large population-matched sample with rigorous statistical methods provides moderate confidence, though cross-sectional design limits causal inference.
When this study was published
2025 publication; survey data matched to 2020 California census, approximately four years after Prop 64 implementation
The bigger picture
Legalization without effective public education creates a knowledge vacuum where users believe they understand the law but actually do not. This pattern likely extends beyond California to every state that has legalized.
Questions still open
- Have other states with legalization done better at educating users about specific regulations? Does knowledge of cannabis regulations affect compliance behavior or health outcomes?
Common questions
Did most cannabis users think they understood Prop 64?
Who was most familiar with Prop 64?
Read the original research
Knowledge and attitudes toward recreational cannabis legalization among California residents: a population-matched questionnaire about Proposition 64.
Journal of cannabis research, 7(1), 42
Citation
Ageze, Daniel; Baird, Sara; Marcotte, Thomas D; Elashmawy, Ahmed; Wong, Angela; Dell'Acqua, Renee; Rybar, Jill; Hacker, Sarah; Gold, Alice; Shaughnessy, Tom; Lanin-Kettering, Ilene; Hill, Linda L. (2025). Knowledge and attitudes toward recreational cannabis legalization among California residents: a population-matched questionnaire about Proposition 64.. Journal of cannabis research, 7(1), 42. https://doi.org/10.1186/s42238-025-00304-9