Background: This paper explores user perceptions and practices in contrasting legal-policy milieux-Amsterdam (de facto decriminalization) and San Francisco (de jure criminalization) on four policy issues: sources of cannabis and separation of markets for it and other drugs; user perceptions of effects of price on consumption; effects of potency on consumption; and perceived risk of arrest and accessibility of cannabis.
Methods: Questions on these issues were added to surveys on career use patterns amongst representative samples of experienced cannabis users using comparable methods.
Results: Most San Francisco respondents obtained cannabis through friends who knew dealers, whereas most Amsterdam respondents obtained it from regulated shops. Only one in seven Amsterdam respondents but half the San Francisco respondents could obtain other drugs from their cannabis sources. Majorities under both systems had never found cannabis "too expensive." Amsterdam respondents preferred milder cannabis whilst San Francisco respondents preferred stronger; majorities in both cities reported self-titrating with potent cannabis. Risk and fear of arrest were higher in San Francisco, but most in both cities perceived arrest as unlikely. Estimated search times were somewhat longer in San Francisco, but a majority reported being able to access it within half a day.
Conclusions: There is substantial separation of markets in the Dutch system. Policies designed to increase cannabis prices appear unlikely to impact consumption. Decriminalization was associated with a preference for milder cannabis, but under both policy regimes most respondents self-titrated when using more potent strains. Criminalization was associated with somewhat higher risk and fear of arrest and somewhat longer search times, but these did not appear to significantly impede access for most respondents.