Studies of individual perceptions of norms suggest that such norms predict marijuana use (Beyers et al., 2004; Botvin et al., 2001; Elek et al., 2006; Hansen and Graham, 1991). These studies, while important, do not provide information on group-level norms, which is needed for several reasons. First, individual perceptions of societal norms may not always be accurate. Second, societal norms may influence behavior independently of individual beliefs. That is, other things being equal, a given individual may be more likely to use marijuana in an accepting than in a non-accepting society, as we recently showed (Keyes et al., In press). Third, policy and program interventions focused on societal norms may have a wider impact than interventions focused on individuals (Chilenski et al., 2010; Lipperman-Kreda and Grube, 2009; Lipperman-Kreda et al., 2010). Therefore, studying the influence of societal-level norms is increasingly important, especially during times such as the present when marijuana use, abuse and dependence are increasing. However, a difficulty in conducting this research is the scarcity of informative societal-level data on groups with differing norms.
