This chapter focuses on the liminal moment, between the failed first attempt to pass the Act in January 1799 and its eventual passage in June 1800, 18 months later. It considers the legal questions about the legitimacy of the Act of Union from two different perspectives. The chapter describes the issue of consent, specifically Ireland's consent to the Union seen as analogous to consent to a contract of marriage. It analyzes the arguments made about the constitutional legitimacy of the Act, which posited Irish claims to superior knowledge and understanding of English constitutional law. Both views demonstrate the mutually constitutive relationship between law and empire and how metropolitan authorities hoped to use the law to fix relationships of power that would build imperial networks to buttress the Empire.