Although constitutional protection for rights is increasingly popular, there is little systematic research on the extent to which bills of rights affect the process of government. This article examines the effects a bill of rights may be expected to produce, and then uses a quasi-experimental design to analyze the effects of the Canadian Charter of Rights and Freedoms on the Canadian Supreme Court's agenda. The data suggest that the Charter indeed has influenced the Court's agenda, although the effects are more limited than generally recognized. More important, the data suggest that a number of the influences often attributed to the Charter likely resulted instead from the growth of what I call the support structure for legal mobilization, consisting of various resources that enable litigants to pursue rights-claims in court. The political significance of a bill of rights, then, depends on factors in civil society that are independent of constitutional structure
