BACKGROUND: Western Australia (WA) became the fourth Australian jurisdiction to adopt a prohibition with civil penalties scheme for minor cannabis offences when its Cannabis Infringement Notice (CIN) Scheme became law on March 22, 2004. Previous criminological research has demonstrated the importance of public attitudes towards the law in determining the effectiveness of legislation. This survey represents the first phase of a pre-post study that attempted to gauge public attitudes towards the legal status of cannabis, the proposed legislative reforms surrounding the drug and their likely effects. METHODS: A random telephone survey of 809 members of the WA population was conducted prior to the implementation of the new laws with a view to exploring contemporary views of the existing legal status of cannabis, attitudes to the proposed legislative model, and respondent perceptions of its likely effects. RESULTS: Despite cannabis being viewed negatively by large numbers of the sample, criminal penalties for minor cannabis offences were viewed as inappropriate and ineffective. Once explained, the proposed civil penalty scheme was viewed as “a good idea” by 79% of the sample, despite significant differences due to personal experience of cannabis use, political affiliation, religiosity, and age of offspring. Most believed that the legislative change would not result in changes to levels of cannabis use (70%) or ease of obtaining cannabis (59%). CONCLUSIONS: These data suggest that prior to its implementation the new legislation was highly acceptable to the majority of the community. These baseline data will be compared with data to be collected at the post-change phase of the study to allow empirical observations of attitudinal and behavioural changes occurring in the community.