1964 Coup d'état

Castello Branco Government

The IAs

Consequences of Dictatorship


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The AIs



What are Institutional Acts (IAs)?

A set of political rules issued by the government to legitimize their actions after the 1964 coup.  


On April 9 1964, military junta de facto took power and issued a set of political rules known as Institutional Act number one (IA-1). Its main author was jurist Francisco Campos, whose experience with authoritarian laws dated back to the 1930s, when he drafted the Constitution of 1937.The Institutional Act strengthened the Executive Branch of government and gave the President power to suspend political rights, eliminate mandates and fire public officials. For this reason, Constitutional guarantees were suspended for up to six months. Therefore it was up to Congress to pick the new president. They chose, General Humberto Castello Branco as President and José Maria Alkmin as the vice president.


Much like the key features of Castello Branco’s government Institutional Act number 2 was simply an extension of his policy as well as the changes that would later on materialize in the Constitution of 1967. Under the strong political tension, on October 27, act number two was issued: it dissolved existing political parties,established indirect presidential elections, and it intervened with the composition of the Supreme Court. This opened up a political crisis within the regime. Paradoxically the military that had promised democracy adopted, more and more, arbitrary measures that strengthen and extend their powers.  


On the night of December 13, 1968, the Institutional Act number five (IA-5) was issued and Congress became closed indefinitely. The government of the new President, Artur da Costa e Silva was, under tight watch after a speech in which Marcio M. Alves called citizens to boycott the September 7 Independence Day festivities.  

Characteristics of the AI 5: 

(1) Granted power to the President to intervene, as he desired in state and national laws without any regrads to the Constitution.

(2) Further granted the President the right to suspend citizen’s rights for a period of up to ten years.

(3) The IA-5 also banned any type of political manifestation against the government. Most importantly,it suspended the right to habeas corpus.

(4) Ihis act imposed heavy censorship in all aspects of society including, but not limited to newspapers, magazines, plays and music. 

Censorship, totures, and murrders of oposition leaders were confirmed by IA-5. In practical terms this was an amendment to the Constitution of 1967, which was based on the National Security Doctrine, which instituted a police state. As a result Brazil became highly endebted because of the various groups that helped finance the 1964 coup.   


< The front cover of the newspaper Jornal Do Brasil. The headline reads:Goverment ratifies Institucional Act and Congress is suspended indefinitely.