With the 1964 Brazilian coup d'état, on April 2 the National Congress of Brazil declared the presidency of the Republic occupied by João Goulart vacant.

With the beginning of the coup, General Nicolau Fico, the army commander in Brasília, had to choose between garrisoning Congress and policing the city, as Auro wished, or not offering this support, as Goulart and Darcy Ribeiro, the head of the President's Civil Cabinet [pt], wanted.

The 1946 Constitution [pt] defined three forms of removal of the President of the Republic: resignation, which did not occur, impeachment, for which the opposition would not have the votes, and vacancy after unauthorized departure from the country.

Although Goulart's whereabouts were communicated to the parliamentarians, Auro de Moura Andrade declared the presidency vacant and quickly closed the tumultuous early morning session.

Meanwhile, on April 2 Goulart still had some power in Porto Alegre, which could even lead to duality of government, but he did not want the conflict and went to the interior of the state.

[6] The president got legislative support to bring forward the referendum on presidentialism, regaining the powers lost to the parliamentary republic [pt],[2] but Congress overturned a constitutional amendment for land reform in May 1963.

[9] This is attributed both to the president's political incapacity, as done by politicians at the time and later authors (Elio Gaspari and Marco Antonio Villa), and, conversely, to the social conflict of the moment making it impossible to build support in Congress.

[10] The basic reforms are also accused, as by Wanderley Guilherme dos Santos [pt], of being, except for the agrarian one, obscure and unclear, only exposed in the presidential message to Congress in 1964, with little initiative taken by the president.

[11] Candidates opposed to the reforms advocated by the left were financed by the Brazilian Institute for Democratic Action, with foreign financial involvement, in the 1962 elections.

[14] In the last moments of his government, as in the Central Rally, the president, as desired by the left, abandoned conciliation and sought to mobilize popular pressure to get the reforms from Congress, thus alarming conservative congressmen.

[23] Auro de Moura Andrade published a manifesto breaking the Senate from the government and calling for the Armed Forces to intervene in the political process.

[27] In Congress, "the stage for harsh, vehement dialogues,[28] congressmen anxiously followed the news of the adhesion of General Amaury Kruel, commander of the Second Army.

[29] Congressman Francisco Julião claimed to have 60,000 armed men from the Peasant Leagues willing to defend the government, which was nothing but bravado, but it intimidated the congressmen.

[31] In the Theater, Darcy Ribeiro, head of Goulart's Civil Cabinet, had organized about a thousand candangos [pt] on the morning of the 1st to, according to him, peacefully occupy the Chamber and Senate on the following day.

[32][33] In another moment, the head of the Civil Cabinet handed weapons and a list of politicians to be arrested or executed (depending on the version), among them the presidents of the Supreme Court (STF) and Senate, to two leaders of the Communist Party [pt].

However, on their way back from the airport they found the Esplanade of the Ministries occupied by the Army, which had ignored Jango's wishes and started carrying out the order of the Senate President.

[43] The congressmen had no patience to wait for the president to leave the country, and so the vacancy was declared without constitutional basis:[44] Goulart not only remained on national territory, but also informed Congress of this fact.

[43] Around midnight, Auro de Moura Andrade was meeting with the leaders of the PSD and UDN, and Tancredo Neves suspected that they were plotting Goulart's deposition.

Suspecting that he would be declared in an uncertain place or outside the country, Waldir Pires drafted an official letter, to be signed by Darcy Ribeiro, clarifying the president's whereabouts.

It was during the suspension that Pedro Aleixo allegedly, Tancredo Neves was informed, suggested a summary coup, making the statement and suspending the session.

[46] Despite having a few MPs of great physical vigor forming a personal safety device,[51] Auro was slapped by deputy Rogê Ferreira, but managed to quickly get out to Ranieri Mazzilli's office.

[46] Fearing a crowd at the bus station and lacking full confidence in the Army, Congress had on hand, on loan from Mauro Borges, three machine guns at strategic points and some ammunition.

[60][a] Statements from military personnel recognize the lack of Congressional obstacles to the deposition of the president and its role in institutionalizing the coup, but while some evaluate positively the motivations of the congressmen, for others they were opportunistic.

[61] Most congressmen justified the measure as a way to restore public order and defend the democratic regime from a socialist revolution or from carrying out base reforms without the consent of Congress.

However, congressmen from the PTB and the Nationalist Parliamentary Front denounced the act, such as Senator Oscar Passos, for whom the session was conducted in a "brutal, illegal and violent" way.

[65] Auro also had a personal motive: in July 1962, during the parliamentary regime, the president nominated him as Prime Minister, under the condition that he kept a letter of resignation.

[66] The course of events up to Castelo Branco's inauguration was remarkably similar to that envisaged in a 1963 American contingency plan: Goulart would be "persuaded" to step aside and Ranieri Mazzilli would occupy his position until the election of a new president by Congress.

With Auro and the president of the Supreme Court (STF), Justice Ribeiro da Costa [pt], he drove in a few cars to the Palace.

[69] A tense argument arose between Fico and Darcy Ribeiro about his loyalty, since he was already taking orders from General Costa e Silva, who had taken over the Ministry of War in Rio de Janeiro.

[69] Mazzilli began his government in Brasília, but power was concentrated in the military constituted in the Supreme Command of the Revolution [pt] in Rio de Janeiro.