A week before Brazil hosts the Olympic Games, a judge has ratcheted up political tensions in the country by ordering former president Luiz Inácio Lula da Silva to stand trial on charges of obstructing justice during a vast corruption investigation at the state-owned oil company, Petrobras.

The court case against the Workers’ party founder – who in 2009 helped to win the Olympic bid for Rio de Janeiro – is likely to cast a shadow over the sporting spectacle and adds to a wave of problems engulfing the country, including a political crisis, the worst recession in decades, pollution fears and the Zika epidemic.



Lula is accused of conspiring to buy the silence of a former Petrobras director, Nestor Cerveró, who was arrested last year as part of the vast – and still ongoing – Lava Jato (Car Wash) investigation into corruption at the state-run oil company.



Ricardo Leite, a federal court judge in Brasília, announced on Friday that there was sufficient evidence to begin criminal proceedings against Lula and six other suspects.



The former president has denied the charges, saying the accusation is based on a mendacious testimony made by former senator Delcídio do Amaral as part of a plea bargain to secure the latter’s switch from jail to house arrest.



“Lula has made it clear in a statement to the attorney general that he never interfered or attempted to interfere with testimony related to Lava Jato,” said a statement from the Lula Institute.



A lawyer for Lula addded: “Lula vehemently denies the claims against him but is not opposed to be investigated in a fair and open manner. In this case, Lula’s lawyers were not asked to put forward a defence. Lula has already testified that he did not try to interfere with the testimonies. Brazil’s judicial system has once again highlighted to the world the challenges of receiving a fair trial in Brazil.”





Along with Lula and Amaral, the defendants list includes Diogo Ferreira (Amaral’s former assistant), banker André Esteves, lawyer Edson Ribeiro, rancher José Carlos Bumlai and his son, Maurício Bumlai.

In an interview with the Guardian earlier this year, Amaral said Lula had asked him to help Cerveró’s family because the former Petrobras director could implicate Bumlai, a rancher and an associate who served as a go-between in negotiations between politicians and oil company officials.

“Look, is there any way we can help Bumlai,” Amaral recalls Lula telling him at a meeting in Brasília. The solution they reached, the former senator says, was that Bumlai’s family would help Cerveró’s family with legal fees. The sum – at least 250,000 reais ($77,000) – was paid with the help of the banker Esteves, then one of Brazil’s richest men. Amaral was later secretly recorded trying to arrange Cerveró’s escape.



The former senator predicted his testimony would soon lead to the arrest of the former president, who was once his ally.

Lula has been under growing legal and political pressure. He was detained for questioning and his home and offices were raided by police in March. Two months later, his successor, Dilma Rousseff, was suspended from the presidency while she undergoes an impeachment trial in the senate on unrelated charges of fiscal irregularities.

Adored as one of the most popular leaders in the world when he left office in 2010, Lula told the Guardian last month that he is the victim of a political witch-hunt that is designed to stop him running again for the presidency in 2018.

He claimed Amaral was lying to secure his release. “He’s built a fantasy narrative to help himself,” he says. The senator denies this and stands by his testimony.

Lula and the other defendants have been given 20 days to present their defence. The trial will take place in Brasília and be presided over by Leite, a judge who was mired in controversy last year when prosecutors asked for him to be withdrawn from a tax fraud case because he was impeding the investigation.

Earlier this week, Lula’s legal team filed a petition with the United Nations human rights committee claiming he was the victim of abuse of power in the corruption case. But that process related to a different legal challenge against him in Curitiba.

Although the former president has not been jailed, the prospect of a trial may further divide the country ahead of the Olympics, which open in Rio de Janeiro next Friday.