The changes were rejected by the majority of voters, resulting in the choice of presidentialism, the end of the Parliamentary Republic established in 1961 and the restoration of the full powers of president João Goulart, also sworn in in 1961.

Goulart's inauguration had been the target of an attempt at a military veto and it was only possible due to a political compromise that resulted in the adoption of parliamentarism to weaken his powers.

In 1962, political crises in July and September, both with general strikes and military pressure, allowed the president to obtain a favorable prime minister and intimidate Congress to bring forward the voting date.

[2] On 24 August 1961, then president Jânio Quadros resigned, seeking to trigger a succession crisis against the inauguration of his vice-president João Goulart, who was on a trip to China.

[3] The possibility of civil war arose, but "following an old national tradition" the solution was a compromise,[4] preserving the president's mandate but weakening his powers through the adoption of parliamentarism.

[15] Since taking office, Goulart articulated the reversion to presidentialism,[5] and at the opening of the 1962 legislative works he explained his intention to regain his powers with an early plebiscite.

[16] The dispute for bringing the referendum forward, driven by trade unionism, military and political pressure, was then won in September by an anti-parliamentary coalition stronger than the parliamentary one — even Goulart's enemies wanted presidentialism.

In his first year in power, he concentrated his forces on bringing forward the plebiscite, and thus had no interest in strengthening the parliamentary regime or in stabilizing the economy through an unpopular fiscal adjustment.

[21] There were difficulties in applying economic policy from the dismissal of Tancredo Neves, in June, to the reschedule vote in September; instability made any stabilization program unfeasible in mid-1962.

For political scientist Argelina Figueiredo, UDN and PSD congressmen were mostly against parliamentarism, but a contrary argument is that, if this was the case, it would not have been necessary to apply so much pressure to bring forward the plebiscite.

Goulart defeated offensives in Congress to consolidate parliamentarism, first in an attempt to pass a complementary law in September 1961, and then in administrative decrees that would strengthen the Council of Ministers.

Carlos Lacerda, from Magalhães party and also running for president, wanted to reverse parliamentary rule and is mentioned among its opponents, but he acted against the referendum.

[40] Tancredo Neves was not dedicated to the preservation of parliamentarism, but his fall was the "beginning of the end" of the regime, as his cabinet, unlike the others that followed, was not formed with the commitment to bring forward the plebiscite and was not dependent on Goulart.

The government wanted to delegate powers to the Council of Ministers to carry out the base reforms, and Brochado da Rocha threatened to resign if Congress did not vote on the plebiscite by 17 August.

On that date, the period of "concentrated effort" in Congress ended and the parliamentarians would leave Brasília to conduct their electoral campaigns; if the cabinet fell, they would need to participate in the formation of a new one.

[46] With the arrival of this period, the UDN and PSD managed to limit one of the advantages of the president — the absence of government during ministerial changes, which could lead to the postponement of the elections.

On 12 September, the UDN and PSD approved the Capanema Law in the Chamber of Deputies, authorizing the president to appoint a provisional cabinet, and it was forwarded to the Senate.

Meanwhile, on the 10th, the CGT made a series of demands: "to bring forward the plebiscite to 7 October, the delegation of powers to the Council of Ministers, the repeal of the National Security Law, a 100% increase in the minimum wage, the granting of the right to vote for illiterates and soldiers, the implementation of a "radical agrarian reform", the freezing of the prices of essential goods and the approval of the bill to regulate the right to strike".

[48] On 13 September, Jair Dantas Ribeiro declared himself incapable of maintaining order in the territory of the 3rd Army "if the people rise up" against Congress for not bringing forward the plebiscite.

[d] Along with the request for a state of emergency in 1963, this was one of the two moments in which Goulart "made use of strong pressure mechanisms, frightening everyone and giving rise to speculation about any unconstitutional plans he might have".

The meaning of this action was, according to historian Carlos Fico, "to lead the National Congress to vote with the government, this way we could perhaps speak of undue pressure, but not coup d'état"; "it is true that Goulart played hard".

For Moniz Bandeira, general Amaury Kruel, head of the Military Cabinet, defended a coup d'état led by the president, and the commanders of the 1st, 2nd and 3rd armies wanted to intervene against parliamentarism.

4 of 2 September 1961 will be submitted to a popular referendum on 6 January 1963.The left wanted the date of 7 October, coinciding with elections for Congress and ten state governors,[69] but this was resisted by conservative politicians who would be harmed by associating their candidacy with the unpopular "yes" option to parliamentarism.

[75] The presentation of the Triennial Plan, devised by economist Celso Furtado for the remaining years of Goulart's term, contributed to the campaign for a return to presidentialism.

[76] Leonel Brizola and Juscelino Kubitschek toured the country campaigning for the "No" vote to parliamentarism,[77] and Magalhães Pinto organized a front of governors in support of presidentialism.

The hopes of the UDN politicians were the thesis of the insufficiency of the plebiscite to revoke the Additional Act and the expectation of low turnout; the latter was defeated when the Electoral Justice determined that voting was mandatory.

"The propaganda machine set up by those in favor of the return of presidentialism, the millions of cruzeiros — denounced by UDN parliamentarians — the posters, jingles, newspaper articles, appeals" worked.

[90] Propaganda for presidentialism blamed inflation and the social crisis on the parliamentary system, making it necessary to empower the president to act against extreme poverty, illiteracy, landlessness and political crises.

[91] At the behest of Darcy Ribeiro's Ministry of Education, the Instituto Superior de Estudos Brasileiros published the pamphlet "Why vote against parliamentarism in the plebiscite?

[2][96] Goulart, having achieved full presidential powers, started his Basic Reforms plan (Reformas de Base), which led to a military coup d'état in April 1964.