Despite the popularity of the Evidence-Based Policy Making paradigm, scholarly evidence often fails to have an impact in emotional or value-laden policy debates. Consequently, changes to Canada’s gun control laws in recent years have often failed to incorporate scholarly research. This is problematic given that the forces of path dependence impose costs on policy makers who seek to reverse established policies, even if they are dysfunctional. This article lays the theoretical foundations for a Firearms Policy Evaluation Framework, which can be used by scholars, policy makers, advocates, and the public to conduct preliminary evaluations of proposed firearms policies before they become law. The utility of the framework is then demonstrated with an evaluation of the 2020 assault-style weapons ban in Canada, which includes a systematic scoping review of the literature on the impact of assault-weapons bans.