Constitutions of exception are commonplace legal regimes that prescribe conditions and procedures under which the constitution itself can be legally suspended. Often the suspension of the constitution involves the interruption of scheduled elections for the national legislature and/or the chief executive. Military participation in civilian government and the derogation of civil liberties and rights are also typical. There is a debate in the literature about the value of exception clauses. We argue that they threaten democratic stability and consolidation. We do this by studying a large panel of countries and their constitutions over the twentieth century.