Can political reform succeed where it has failed so many times before?

Proposals to reform Brazil’s system of government is a hardy, perennial issue in the country’s political debate. Periodically, policymakers and pundits float proposals to replace Presidentialism — adopted in 1889 after the military coup that ended Brazil’s oligarchic constitutional monarchy — with systems in which the current separation of both origin and responsibilities between the head of government and the parliament decreases. 

The goal is to eliminate what has been, historically, one of the main sources of political instability in the country: presidents who, in the face of resistance from Congress, manage to expand the president’s power. By tying the origins and responsibilities of the head of government to parliament, advocates of reform hope...