Diretas Já

Although the idea for creating a constitutional amendment to reestablish direct presidential elections cannot be credited to Oliveira entirely, his proposed amendment and its subsequent failure in the National Congress had massive repercussions, as the movement for direct democracy in Brazil grew beyond the Congress, and became a popular movement in Brazil known as Diretas Já.^[2] The first mass protest for the reimplementation of direct democracy occurred in the city of Abreu e Lima in Pernambuco on 31 March 1983, sprouting protests in São Paulo. These sporadic protests later became an organized movement, beginning with a protest of 30,000 people in Curitiba on 12 January 1984, spreading to most every major city in Brazil from then on.^[6]

Fearful of what was occurring in Congress, then leader of the military dictatorship João Figueiredo strongly pressured members of the dictatorship-aligned PDS to vote down the measure. Along with, Oliveira received a note from Tancredo Neves that affirmed that Oliveira's amendment was all but likely to be voted down.^[7] Despite this, the central faction of the movement began to take to the streets, with an IBOPE poll taken on the eve of the eventual vote showing that 84% of those questioned approved of the amendment. As a last minute effort to stave off the movement, the federal government put forward their own amendment, dubbed the "Figueiredo amendment" which, among other things, would have prevented the reestablishment of direct elections until 1988.^[7] The Dante de Oliveira amendment, however, was ultimately put to a quorum vote on 25 April 1984, but did not obtain the 2/3rds vote in order to bring the measure to a full vote in Congress, largely due to the absence of the PDS members in Congress.^[4] The outcome deepened the already stark divisions and contributed to Neves' landslide win in the 1985 presidential election.^[8]

Post-dictatorship political career

In 1985, Oliveira was elected to be the mayor of Cuiabá for the PMDB. He only served several months out of his first term before being tapped by then-president José Sarney in 1986 to be the Minister of Agrarian Development. His vice-mayor, Estevão Torquato da Silva, succeeded him. He returned to his post as mayor in 1987 and attempted to resolve the city's financial shortcomings.^[4] After his departure from the mayoralty in 1989, in 1990, he switched his affiliation to the Democratic Labour Party (PDT). Afterwards, he ran as a federal deputy for that year's elections, but was not elected. He ran again and was elected mayor of Cuiabá for another term. He resigned from the position in 1994 to become the governor of Mato Grosso. After prolonged disagreements with the PDT, Oliveira was expelled from the party due to their discontinued support of him.^[4] He subsequently switched affiliations to the PSDB and won reelection in 1998. His political reputation was damaged when it was alleged that João Arcanjo Ribeiro, who was involved with organized crime in Cuiabá, helped fund his reelection campaign in 1998.^[9] He left the position to run for senator for Mato Grosso in 2002, but was not elected.^[4]

In 1995, then-president Fernando Henrique Cardoso awarded Oliveira the Grand Officer class of the Order of Military Merit by decree.^[10]

Death

While tentatively planning to run once more as a federal deputy, Oliveira died on 6 July 2006 in Cuiabá due to pneumonia that was exacerbated by complications from diabetes.^[9] After his death, there were various homages to him and his legacy, including the renaming of Avenida dos Trabalhadores in Cuiabá to Avenida Governador Dante Martins de Oliveira.^[11] He is buried in Piedade Cemetery, the oldest cemetery in the Cuiabá, within the Historic Center of Cuiabá.^[12]