BRASILIA (Reuters) - Brazil's Supreme Court decided on Thursday to end the mandatory imprisonment of convicted criminals after they lose their first appeal, restoring the previous rule that they should be allowed to exhaust all their appeal options before being locked up.
The politically charged re-interpretation of Brazil's penal code could lead to the release of dozens of high-profile convicts, including former leftist president Luiz Inacio Lula da Silva, jailed last year for taking bribes.
By a 6-5 vote, the court overturned a three-year-old rule that contributed to the success of Brazil's biggest corruption investigation, the so-called Car Wash operation that put dozens of company executives and politicians in jail for bribes and kickbacks.
The prospect of serving immediate prison time after losing a first appeal encouraged suspects to negotiate plea deals with prosecutors, providing them with information that helped unravel the biggest graft scheme in Brazil's history.
Lula was jailed in July 2018 for eight years and 10 months after he was found guilty of taking bribes from engineering firms in return for government contracts. His lawyers are expected to swiftly file for his release at the lower court that convicted him.
Lula governed Brazil from 2003 to 2010, its first working class president. He left office with sky-high popularity ratings thanks to social policies that raised millions from poverty, but his critics say he ruined the country by allowing corruption to flourish.
Lula's release would heighten tensions in a polarized nation that elected far-right President Jair Bolsonaro last year. Lula had been favorite to win the 2018 election but his imprisonment barred him from running.
Sergio Moro, the judge who handled most of the Car Wash trials who is now justice minister in Bolsonaro's government, warned before the court's decision that overturning the rule would be a big setback for the fight against corruption.
According to the National Council of Justice, some 4,895 convicts could potentially benefit from the rule change.
The Brazilian Bar Association argued that the mandatory prison rule violated the constitution by not respecting the presumption of innocence of defendants throughout the appeals process.
Anti-corruption movement Vem Pra Rua, or 'Take to the Streets,' had published full-page ads in newspapers saying the expected court ruling would be a terrible setback.
"We fear Brazil will become known as the country of impunity," the group said. It announced protests in Brazilian cities on Saturday.
(Reporting by Anthony Boadle and Ricardo Brito; Editing by Sandra Maler and Rosalba O'Brien)