Cristina Fernández de Kirchner, Argentina’s former president and one of the country’s most polarizing political figures, was sentenced to prison on Tuesday and barred for life from public office after the Supreme Court upheld her corruption conviction.
The ruling is likely to deepen political tensions in the country and comes after Mrs. Kirchner, who was the target of an assassination attempt three years ago, announced plans for a political comeback.
Supporters blocked key highways around the capital, Buenos Aires, ahead of the court decision against the left-leaning Mrs. Kirchner, who has clashed repeatedly with Argentina’s right-wing president, Javier Milei, while major labor unions had threatened national strikes.
The Supreme Court rejected an appeal by Mrs. Kirchner in a 27-page ruling, cementing a six-year sentence handed down by a lower court that had found she defrauded the state during her two terms as president, from 2007 to 2015.
Still, Mrs. Kirchner, 72, is unlikely to serve significant prison time as Argentine law often allows house arrest for those over age 70. The lower court, which will determine if Mrs. Kirchner gets home detention, said she had five business days to present herself before the tribunal to be officially detained. Separately, it asked the security minister to provide an appropriate place for her detention.
The former president could be held behind bars for a few days until a judge approves her home detention, said Andrés Gil Domínguez, a constitutional law professor at the University of Buenos Aires.
Mrs. Kirchner told supporters outside her party’s headquarters shortly after the court ruling, “This Argentina we’re living in today never ceases to surprise us.” She called the three members of the Supreme Court “puppets” and characterized them as “a “triumvirate of disgraceful figures” who answered to powerful economic interests, and said they were now “imposing a clamp on the popular vote.”
As for Mr. Milei, he wrote, “Justice” on X and reposted several messages that celebrated the Supreme Court’s ruling.
A fixture in Argentine politics for more than three decades, Mrs. Kirchner remains a divisive figure. While much of the country views her presidency as synonymous with economic mismanagement and corruption, she continues to command a loyal base that credits her with expansive social programs.
Mrs. Kirchner, who was also vice president from 2019 to 2023, has faced numerous charges of corruption. She was convicted in 2022 of steering public roadworks contracts in a southern province to a family friend and business associate.
Mrs. Kirchner has denounced the charges as politically motivated, accusing opponents of weaponizing the judiciary to curb her influence.
The court determined that the scheme had began under her husband and predecessor, Néstor Kirchner, and continued during her two presidential terms. He had been governor of southern Santa Cruz Province and served as president from 2003 to 2007. Mr. Kirchner died in 2010.
Since 2024, she has led the Justicialist Party, the main opposition force to Mr. Milei and the largest political platform for Peronism, the populist, nationalist movement that has shaped much of Argentina’s modern political history.
Mr. Milei has frequently blamed Mrs. Kirchner, as well as her husband, for years of economic mismanagement and systemic corruption that sent the country into a downward economic spiral. Mr. Milei won office in 2023 by vowing to slash public spending and overhaul Argentina’s state-heavy economy.
Mrs. Kirchner recently announced that she was running for a seat in the Buenos Aires provincial legislature in elections this year. She would have been a heavy favorite, and a victory would have granted her immunity from serving the sentence.
“Coincidence is not a political category,” Mrs. Kirchner told supporters on Monday as she prepared for the decision from Argentina’s highest court. “It only took us announcing a candidacy a week ago for the demons to be unleashed.”
She characterized efforts to imprison her as a way to quiet her criticism of Mr. Milei’s right-wing economic policies, which have included broad austerity measures.
“Go ahead, throw me in prison,” she said Monday. “Do you really believe this will fix anything? I might be behind bars, but people will be worse off by the day.”
During Mrs. Kirchner’s trial in 2022, supporters gathered outside her Buenos Aires apartment every day to show solidarity.
In September of that year, a man at the entrance to her building pointed a loaded pistol at her head at close range. The weapon jammed, and she was uninjured. The accused gunman and two others are detained and facing trial.
The former president faces several other legal issues, including accusations of money laundering, orchestrating a corruption scheme involving public works and conspiring with Iran to cover up its suspected role in the 1994 bombing of a Jewish community center in Buenos Aires that killed 85 people.
