BRASILIA, June 9, 2025 (BSS/AFP) - Brazil's right wing former president Jair Bolsonaro will appear at the Supreme Court Monday, facing charges of trying to stage a coup to retain power after losing the 2022 elections.

In February, prosecutors accused the 70-year-old far-right leader, who governed Brazil from 2019 to 2022, of leading a "criminal organization" plotting to overturn the election results and preventing the inauguration of leftist President Luiz Inacio Lula da Silva.

The plot failed, the charge sheet says, because of a lack of military backing.

Bolsonaro also stands accused of having been aware of an alleged plot to assassinate Lula, his vice president Geraldo Alckmin, and judge Alexandre de Moraes -- an arch-foe.

Bolsonaro, who is hoping to make a comeback in 2026 presidential elections despite being barred from running, denies the charges.

He, along with seven other former aides, are facing sentences of up to 40 years behind bars if convicted.

- 'Moment of truth' -

Although he has the right to remain silent, Bolsonaro told reporters last week that he plans to respond "without any problem" to questions from the court.

"It's an excellent idea to speak openly about the coup. I will be very happy to have the opportunity to clarify what happened," the former army captain said on Thursday.

"It's the moment of truth."

The Supreme Court headquarters in Brasilia, where Bolsonaro will take the stand, is one of the buildings raided by his supporters, known as the Bolsonaristas, in January 2023 as they urged the military to overthrow Lula.

Testimonies will be broadcast live and could last all week.

Bolsonaro figures sixth on the list of witnesses and is expected to take the stand on Tuesday or Wednesday.

For the former president, the trial will mark a reunion with former allies and sworn enemies.

Seven of his co-defendants have also been called to testify, including his former right-hand man Mauro Cid, who has been labeled a traitor by the Bolsonaristas for turning state's witness.

Cid's testimony allowed the police to identify the various actors in the coup plot and to lay hands on compromising information exchanges, according to the investigation.

Four former ministers and the former heads of Brazil's navy and intelligence agency will also be seated in the dock.

While on the stand, Bolsonaro will not only face questions from prosecutors and defence attorneys, but also judge Moraes, whom the former president calls a "dictator."

- 'History' in the making -

The judicial process has been swifter than usual in this case, said Rogerio Taffarello, a criminal law expert at the Getulio Vargas Foundation.

But the end is still a way off, with the court able to call new witnesses as the trial proceeds before getting to the closing arguments and sentencing deliberation.

Since the alleged plot was conceived over a long period, and because some of the charges brought are new to the Brazilian system, "an extremely complex legal discussion" is expected, Taffarello told AFP.

Bolsonaro spent the weekend with his lawyers preparing his testimony at the residence of Sao Paulo state governor Tarcisio de Freitas, local media reported.

In a preliminary phase, Freitas, who served as Bolsonaro's infrastructure minister, testified for the defence, insisting his boss had "never touched" on the subject of a coup or "mentioned any attempt at constitutional disruption."

But two former army commanders confirmed that Bolsonaro had hosted a meeting where the declaration of a "state of siege" was discussed as a means to overturn Lula's election victory.

"Brazil's history will be written," Marcio Coimbra, head of the Casa Politica think tank told AFP, pointing out that the trial marked the first ever for an attempted coup under a democratic regime in the country.