Ex-president Jair Bolsonaro faced an eight-year ban on running for office as Brazil's top electoral court began trying the far-right leader Thursday over his unproven allegations against the voting system during last year's elections.

Bolsonaro, 68, was not in court as the Superior Electoral Tribunal (TSE) opened his trial on charges he abused his office and misused state media when he convened foreign diplomats in July 2022 to warn of the alleged risk of fraud in the October elections, which he went on to lose to veteran leftist Luiz Inacio Lula da Silva.

After just over three hours of hearings, at which lawyers for the prosecution, defense and the left-wing party that brought the case, the Democratic Labor Party (PDL), made their arguments, the court adjourned until Tuesday, when its seven judges will begin delivering their rulings one by one.

Prosecutor Paulo Gonet Branco said Bolsonaro's speech to ambassadors "was aimed at giving the false impression the voting process is obscure, rigged to manipulate the results and award a fraudulent victory to (his) adversary."

He blamed the former president's statements for the riotous aftermath of the elections, when Bolsonaro supporters invaded the presidential palace, Congress and Supreme Court on January 8, a week after Lula's inauguration.

Insiders say Bolsonaro will almost certainly be found guilty, taking him out of the next presidential elections, in 2026.

His lawyer told journalists he would appeal to the Supreme Court if convicted.

- 'Dreyfus affair' -

Bolsonaro was following the trial from the southern city of Porto Alegre, where he was holding political meetings.

Smiling and waving, he was welcomed at the airport by a boisterous crowd of dozens of cheering supporters, many clad in the yellow and green of Brazil's flag, which Bolsonaro has adopted as a symbol.

The ex-army captain reiterated Wednesday that he had done nothing wrong.

"There was no criticism or attack on the electoral system" at the meeting, he said.

His lawyer, Tarcisio Vieira, argued the same before the court, comparing the case to that of wrongly convicted French Jewish army captain Alfred Dreyfus in the 19th century.

That case "became one of the biggest judicial mistakes in history," he said.

He urged the court not to do the same with Bolsonaro, denying he violated the law at the July 2022 meeting and rejecting efforts to link his statements to the January 8 riots.

Prosecutors say Bolsonaro's briefing to diplomats violated electoral law, both with its content and the fact it was organized with state resources, held in the official presidential residence and broadcast live on public TV in the middle of the polarizing election campaign.

Bolsonaro spent nearly an hour making his case at the meeting, armed with a PowerPoint presentation but no hard evidence to back his claim that the electronic voting machines Brazil has used since 1996 compromised the "transparency" of the elections.

- Slew of probes -

Both Bolsonaro's unsubstantiated allegations of election fraud and the January 8 riots drew widespread comparisons to his political role model Donald Trump and the latter's bid to hang onto power after his loss in the 2020 US presidential election.

Bolsonaro, who spent three months in the US state of Florida after his election loss, has kept an uncharacteristically low profile since returning to Brazil in March to serve as honorary president of his Liberal Party (PL).

He faces a raft of other legal woes, from five Supreme Court investigations that could potentially send him to jail -- including over the January 8 attacks -- to police probes into allegations of a faked Covid-19 vaccination certificate and diamond jewelry snuck into the country from Saudi Arabia.

But the man dubbed the "Tropical Trump" remains a powerful force in Brazil.

He lost the runoff election by a narrow 1.8 percentage points, and conservative parties hold a strong majority in Congress.

Bolsonaro "has a large base that is very much influenced by him," said political scientist Marco Antonio Teixeira, of the Getulio Vargas Foundation.

Even if convicted, "he'll act behind the scenes and use his vote-winning power and influence to help other candidates," he said.

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