Mark Tushnet is William Nelson Cromwell Professor of Law Emeritus at Harvard Law School. He clerked for Justice Thurgood Marshall before beginning his teaching career. He has written more than a dozen books, including Weak Courts, Strong Rights: Judicial Review and Social Welfare Rights in Comparative Constitutional Law (2008) and Advanced Introduction to Comparative Constitutional Law (2014). He was President of the Association of American Law Schools in 2003, and in 2002 was elected a fellow of the American Academy of Arts and Sciences.

1. Introduction; 2. Why a fourth branch - the structural logic; 3. Why a fourth branch - the functional logic; 4. Design issues in general; 5. Design principles in practice - a survey; 6. Anticorruption investigations - case studies from Brazil and South Africa; 7. Electoral commissions - case studies from India, the United States, and South Korea; 8. Audit agencies; 9. Conclusion.

Analyses why constitution-designers have come to establish institutions protecting constitutional democracy in modern constitutions.