With two votes outstanding, the trial could yet be postponed to a later date for the final ruling.
The tribunal is trying the former president on charges he abused his office and state media in making unfounded allegations of security flaws in Brazil's electronic voting system.
Prosecutors have linked Bolsonaro's statements to his supporters invading the presidential palace, Congress and Supreme Court on January 8, a week after the inauguration of leftist Luiz Inacio Lula da Silva.
Lula had defeated Bolsonaro, 68, in elections last October.
After hearing evidence in the case, the judges started delivering their verdicts one by one on Tuesday.
If convicted, Bolsonaro will be ineligible to stand in the next presidential election in 2026, opening the contest for a new leader of the political right.
Bolsonaro was not in court in Brasilia, traveling instead to Belo Horizonte in Brazil's southeast, where he was scheduled to have lunch with members of his Liberal Party.
On Thursday, he insisted he was innocent, telling reporters: "Wanting to take away my political rights for abuse of political power is inexplicable."
'Collective paranoia'
The charges arise from a televised meeting Bolsonaro held with foreign diplomats from the presidential residence in July 2022, three months before his election defeat to Lula.
Bolsonaro spent nearly an hour making his argument to the assembled ambassadors, armed with a PowerPoint presentation but no hard evidence to back his claims that electronic voting machines in use since 1996 compromised election transparency.
The lead judge on the case, Benedito Goncalves, ruled Tuesday to convict Bolsonaro, saying he had used "violent speech and lies" that "endangered the credibility" of Brazil's electoral system.
Goncalves said the briefing "served to incite a state of collective paranoia" about elections at a time Brazil was deeply polarized.
"He instigated a belief that there was a real threat the results of the 2022 election would be adulterated," said the judge.
"It was extremely harmful to the democratic environment."
On Thursday, judge Floriano Marques also voted for conviction and posed the question: "What could be more serious (than) a head of state who, with electoral objectives, mobilizes the apparatus of the Republic to intentionally convey the idea that Brazilian elections are not clean?"
Colleague Raul Araujo, however, voted for acquittal. He said the "gravity of the comportment was not sufficient to justify the extreme measure" of electoral ineligibility.
Nearly half the electorate voted for Bolsonaro in last October's second round, but it was not enough for a win.
Bolsonaro's lawyer Tarcisio Vieira has said he would appeal any guilty verdict to the Supreme Court.
Bolsonaro's unsubstantiated talk of election fraud and the January 8 riots drew comparisons to his political role model, Donald Trump and his bid to hang onto power after losing the 2020 US presidential election.
Nicknamed the "Tropical Trump," his presidency was controversial: at the height of the Covid-19 pandemic that claimed more than 700,000 lives in Brazil, he mocked face masks, social distancing and vaccines, warning the jab could "turn you into an alligator."
He also faced an international outcry over the destruction of the Amazon rainforest, which surged on his watch.
Bolsonaro spent three months in the United States after his term came to an end, and has kept an uncharacteristically low profile since returning to Brazil in March to serve as honorary president of his Liberal Party.
He faces a raft of legal woes. Any one of five Supreme Court investigations could send him to jail -- including over the January 8 attacks.
The police are also investigating claims of a fake Covid-19 vaccination certificate and of diamond jewelry snuck into the country from Saudi Arabia.
© 2023 AFP
