Abstract
This paper seeks to examine the available constitutional models of theories of emergency powers. Part I of the paper traces the historical origins and the subsequent development of emergency states, drawing lessons from the works of Machiavelli, Schmitt, Rossiter, Rousseau... Part II presents and discusses some of the most important contemporary theories of emergency powers that propose different views and perspectives on the central issue of the attribution and exercise of State powers in times of emergency, i.e., either in the hands of the executive, the legislative or the judicial branch of the state, and why. Part III illustrates the concerns pertaining to emergency powers by looking at examples of three specific countries, namely Vietnam, India and Canada.