This chapter examines the state legislature theory related to election laws, focusing on a significant Pennsylvania case regarding mail-in ballot deadlines and the interplay between state courts and legislatures. It discusses the potential chaos that could arise from state legislatures overriding election results, particularly in swing states, and the implications for the electoral vote process in Congress. The chapter also highlights the importance of integrity in the electoral process and the political dynamics at play among senators amidst ongoing debates over election legitimacy.