Who Is Gilmar Mendes? Brazil’s Supreme Court Dean

Updated 4 times · Latest: 16 October 2026

Gilmar Mendes, 70, is a justice of Brazil’s Supreme Federal Court (STF) and its dean, the longest-serving active member. He was appointed in 2002 and is at the centre of this autumn’s fight over the Banco Master inquiry and over whether senators can impeach justices.

This profile covers his career, his main rulings and the controversies around him, each tied to a named source. It is updated as the court and the Senate act, and our guide to Brazil’s Supreme Court explains how the STF works.

Who Is Gilmar Mendes?

Gilmar Ferreira Mendes was born on 30 December 1955 in Diamantino, Mato Grosso. He is the dean of the STF, the justice with the longest service on the bench, and took office on 20 June 2002 after his appointment by President Fernando Henrique Cardoso.

He studied law at the University of Brasília, earned a master’s degree there in 1987, and completed a master’s degree and a doctorate at the University of Münster in Germany. Brazilians also search for him as “ministro Gilmar Mendes” and “Gilmar Ferreira Mendes”.

Career and Positions

Before joining the court, Mendes was Attorney-General of the Union, the government’s chief legal adviser, from January 2000 to June 2002. He took the STF presidency on 23 April 2008 and held it until 2010, a post that also heads the National Council of Justice (CNJ), the judiciary’s oversight body.

He is also a partner in the Brasília law school IDP, which his son Francisco directs. Critics of single-justice orders at the court use the term “ministrocracia”.

Key Controversies and Rulings

Landmark Rulings

As rapporteur of case RE 635,659, Mendes guided the court’s ruling of 26 June 2024 that carrying cannabis for personal use is an administrative, not a criminal, matter, with up to 40 grams or six plants presumed to be personal use; the vote was 6 to 5. On 26 June 2025 he was among eight justices who declared article 19 of the Marco Civil da Internet, Brazil’s internet law, partly unconstitutional, making platforms liable for some illegal user content; three justices dissented.

His rulings on public spending and elections also drew attention, including the 18 September 2026 Bolsa Família decision covered below. Under current rules he reaches the mandatory retirement age of 75 on 30 December 2030.

The December 2025 Impeachment Ruling

On 3 December 2025 Mendes suspended parts of the 1950 Impeachment Law, ruling that only the Prosecutor-General’s Office (PGR) may file impeachment charges against STF justices and that the Senate needs a two-thirds vote to open the process. Senate President Davi Alcolumbre criticised the decision in a plenary speech that day.

On 10 December Mendes suspended the part of his ruling that reserved filing to the Prosecutor-General, at the request of the Senate’s legal advisers, at least until Congress votes an update to the law. The two-thirds rule remains in force, and conviction of a justice in the Senate requires 54 of 81 votes.

The Senate Inquiry Report

On 14 April 2026 the Senate’s organised-crime inquiry (CPI do Crime Organizado) voted down its final report by six votes to four. The report, by Senator Alessandro Vieira, had asked for the indictment of Mendes, Alexandre de Moraes, Dias Toffoli and Prosecutor-General Paulo Gonet for crimes of responsibility, and Mendes called it a “historic error”.

IDP and the Football Confederation

In 2023 IDP signed a contract to run the CBF Academy, the Brazilian Football Confederation’s coach-training courses, and it takes 84% of the academy’s revenue. Gazeta do Povo put the academy’s revenue at about R$9.2 million a year (about US$1.8 million at R$5.01 per dollar).

A city councillor asked prosecutors to investigate Mendes over his rulings in favour of the CBF’s then president, Ednaldo Rodrigues. Deputy Prosecutor-General Hindenburgo Chateaubriand archived the request in August 2025 for lack of minimum evidence, and Mendes has said he sees no conflict.

The Banco Master Case

The Central Bank liquidated Banco Master in November 2025, after its owner, Daniel Vorcaro, was arrested. Six justices are referenced in the investigation: Moraes, André Mendonça, Mendes, Luiz Fux, Toffoli and Kassio Nunes Marques, and the reports stress that a reference does not mean they committed a crime.

Our earlier reports cover his meeting with Vorcaro, his clash with Moraes and his complaint against Chief Justice Fux.

What Gilmar Mendes Said and Did Recently

On 18 September 2026 Mendes, as the case’s rapporteur, upheld the government’s 15.04% Bolsa Família increase and ruled that it does not violate the election-year restriction. He said the figure only restores inflation, measured by the INPC consumer price index from March 2023 to August 2026, so the minimum benefit rises from R$600 (about US$120) to R$691 (about US$138).

On 28 September he put a procedural motion to the court asking it to suspend the proceeding on whether to open an inquiry into Moraes in the Banco Master case until every justice referenced in the investigation is identified. He argued that the court should not decide before it is clear who may take part in the vote.

On 14 October reports said part of the court wants to conclude the internal inquiry by the December recess, which begins on 20 December, to reduce impeachment pressure from senators who take office in 2027. The Federal Police are to deliver their report after 26 October, then the Prosecutor-General’s Office (PGR) gives an opinion and the full court decides whether to open inquiries.

How Brazil’s Supreme Court Works

The STF has 11 justices, whom the president appoints and an absolute majority of the 81-member Senate, at least 41 votes, must approve. Justices serve until the mandatory retirement age of 75.

The court rules on constitutional questions, tries members of Congress and ministers for some crimes, and settles disputes between the federal government and the states. Individual justices can issue interim orders that take effect at once, which critics call “ministrocracia” and which the full court then reviews.

Why Gilmar Mendes Matters for Brazil

Mendes is the court’s dean and one of its most influential votes, so his decisions on elections, public spending and the limits of congressional power shape the rules of Brazilian politics. For investors, the standoff between Congress and the STF is a live institutional-risk factor in the election cycle.

The unresolved Banco Master references and the debate over the Impeachment Law test how far the court can police itself. The answer will matter after the new Senate takes office in February 2027.

What to Watch

Watch the Federal Police report due after 26 October and the opinion of the Prosecutor-General’s Office (PGR). Watch also whether the court acts on Mendes’s motion and whether Congress takes up an update to the Impeachment Law.

Frequently Asked Questions

Who is Gilmar Mendes?

Gilmar Mendes is a justice of Brazil’s Supreme Federal Court (STF) and its dean, appointed in 2002 by President Fernando Henrique Cardoso. He presided over the court from 2008 to 2010.

How old is Gilmar Mendes?

He is 70. Gilmar Ferreira Mendes was born on 30 December 1955 in Diamantino, Mato Grosso.

Why is Gilmar Mendes at the centre of the impeachment debate?

On 3 December 2025 he ruled that only the Prosecutor-General may file impeachment charges against STF justices and that the Senate needs a two-thirds vote to open the process, and Senate leaders objected. On 10 December he suspended the Prosecutor-General-only part at the Senate’s request, but the two-thirds rule remains.

Can an STF justice be removed?

Yes, the Senate can convict a justice of a crime of responsibility, which requires a two-thirds vote of 54 of 81 senators. In practice the Senate president decides whether a request advances to a vote.

Is Gilmar Mendes under investigation in the Banco Master case?

He is one of six justices referenced in the investigation, but the reports stress that references do not mean a crime was committed. The Federal Police report is due after 26 October, and the full court then decides whether to open inquiries.

What did Gilmar Mendes rule on Bolsa Família?

On 18 September 2026 he upheld the government’s 15.04% increase, lifting the minimum benefit from R$600 (about US$120) to R$691 (about US$138). He said it only restores inflation and does not break the election-year rule.

Sources: Brazilian Constitution, article 101; Supreme Federal Court (STF) rulings and the Senate record of 3 and 10 December 2025; Senate organised-crime inquiry vote, 14 April 2026, as reported by Congresso em Foco and Diario de Pernambuco; TSE and Congresso em Foco biographical data; Diario de Pernambuco and Brasil Paralelo (28 September 2026); Agência Estado and Estadão Conteúdo (14 October 2026); Gazeta do Povo and Congresso em Foco (18 September 2026); Gazeta do Povo, O Povo and Band on the CBF Academy contract and the August 2025 decision; Central Bank of Brazil PTAX rate, 13 October 2026.

For the institutional angle, how the STF works, its eleven justices and its powers, read our guide to Brazil’s Supreme Court. For the election context, see our Brazil election results hub and our Pablo Marçal profile.

This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error · Editorial responsibility: Matthias Camenzind, Editor-in-Chief

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