Former Brazilian President Luiz Inacio Lula da Silva was released from prison on Friday after a judge ordered his release.
The order came one day after the country's Supreme Court overturned a law requiring the imprisonment of convicted persons after the loss of their first appeal.
Lula was imprisoned in 2018 for eight years and 10 years after being found guilty of receiving bribes from engineering firms in return for government contracts.
Thursday's controversial Supreme Court decision could benefit dozens of other senior prisoners and thousands of other convicts.
According to analysts, the prospect of imminent imprisonment following the loss of a first appeal encouraged the suspects to negotiate with prosecutors on opposition procedures and provided information that helped decipher the largest corruption scheme in Brazil's history.
The law had helped Brazil's largest corruption investigation, the so-called "car wash," arresting dozens of corporate executives and politicians for bribery and bribes.
The carwash prosecutor said the ruling would complicate their work and favor impunity, as "excessive" appeals were initiated in Brazil. They said in a statement that the court's decision was not in sync with a country that wanted to end corruption.
Brazilian Justice Minister Sergio Moro said on Friday that the Supreme Court ruling should be respected.
Moro was the judge of the car wash trial that condemned Lula before he was appointed Minister of Justice by President Jair Bolsonaro The rule would be a major setback for the fight against corruption.
"Not eligible for election"
Lula, Brazil's first working-class president, was the country's leader between 2003 and 201
Critics accuse him of ruining the country by causing corruption to flourish.
His release is likely to exacerbate tensions in a polarized country that last year elected far-right President Bolsonaro .
Lula is free to engage in politics but is not eligible under the Brazilian Clean Record Act to seek an elected office eight years after his first conviction in June 2017.
"Lula is not eligible to vote, but it is not necessary for him to be the center of attention," said political scientist Alberto Almeida.
"He can pull more politicians from the middle and end up as a dealmaker for his party's candidate in the 2022 presidential election."
Al Jazeera and news agencies