What is the effect of revolutions on legal systems? What role do constitutions play in legitimating regimes? How do constitutions and revolutions converge or clash? Taking the Arab Spring as its case study, this book explores the role of law and constitutions during societal upheavals, and critically evaluates the different trajectories they could follow in a revolutionary setting. The book urges a rethinking of major categories in political, legal, and constitutional theory in light of the Arab Spring. The book is a novel and comprehensive examination of the constitutional order that preceded and followed the Arab Spring in Egypt, Tunisia, Libya, Morocco, Jordan, Algeria, Oman, and Bahrain. It also provides the first thorough discussion of the trials of former regime officials in Egypt and Tunisia. Drawing on a wide range of primary sources, including an in-depth analysis of recent court rulings in several Arab countries, the book illustrates the contradictory roles of law and constitutions. The book also contrasts the Arab Spring with other revolutionary situations and demonstrates how the Arab Spring provides a laboratory for examining scholarly ideas about revolutions, legitimacy, legality, continuity, popular sovereignty, and constituent power.