Two far leftist groups occupied a luxury beachfront triplex property Monday that Brazilian police say leftist ex-president and current presidential frontrunner Luiz Inácio Lula da Silva received as part of a kickback from companies benefitting from corruption during his tenure.

The “triplex” became the key piece of evidence that Lula, as he is typically known in Brazil, had received bribes as part of a corruption scheme known as “Operation Car Wash,” in which dozens of politicians from every major party in the country allowed private contractors to overcharge on government projects in exchange for some of the excess cash. Lula began a 12-year prison sentence this month after being convicted on corruption charges, losing his first appeal, and having a habeas corpus petition to keep him out of prison until his second appeal occurred rejected.

Prosecutors alleged—and in Lula’s case, proved via conviction—that the politicians would grant contracts for projects out of Petrobras, the state oil company, at prices far higher than the average to corporations who would agree to share the money. Prosecutors first called Lula into questioning in March 2016, asking him whether he received ownership of the beachfront property as a gift in gratitude for facilitating the Petrobras scheme.

At the time, Lula vehemently denied the charges.

“I am speaking as an outraged citizen. I have a known public history. Only Jesus Christ can beat me in Brazil,” he told reporters, insisting that he “created the most important leftist party in Latin America” and had done no wrong.

Lula remains the frontrunner in the 2018 Brazilian presidential race, according to a poll published Sunday by the firm Datafolha. He is barred from appearing on the ballot, however, by Brazil’s “Clean Slate” law, which was passed during Lula’s first term in office between 2003-2011.

The leftist groups occupying Lula’s property in the beach town of Guarujá have done so in his defense. They contend that, if the allegations are true and Lula did own the property, then following its seizure it became public property, and it is legal for them to occupy it. If the property is not in public hands, then it belongs to someone other than Lula, which means the evidence that put Lula in jail is not true.

Guilherme Boulos, the head of the Homeless Workers Movement and a candidate for the presidency representing the Socialism and Freedom Party (PSOL), posted photos of the occupied apartment on Twitter. Shortly before his arrest, Lula praised Boulos in a public speech, as he had become a fixture in the metalworkers’ union office that Lula hid in after initially refusing to accept his arrest.

“If it is Lula’s, the people can stay. If it isn’t, then why is he in jail?” Boulos asked.

MTST e a Povo Sem Medo acabam de ocupar o triplex do Guarujá, atribuído a Lula por Moro. Se é do Lula, o povo poderá ficar. Se não é, por que então ele está preso? #Lulalivre #Vamos2018 📸@midianinja pic.twitter.com/LPNhkPq23E — Guilherme Boulos (@GuilhermeBoulos) April 16, 2018

Activists adorned the apartment’s balcony with a banner that read, “If it is Lula’s, it is ours!” and “If not, why did you arrest him?”

The activists will reportedly stay in the apartment indefinitely, or until police remove them. Lula will begin his final appeal before he can take the case to the Superior Court of Justice (STJ) – the non-federal supreme court – on Wednesday.

Lula da Silva remains the most popular presidential candidate for 2018, despite it being illegal for his name to appear on the ballot after his conviction. A Datafolha poll released Sunday found that 31 percent of likely voters would support Lula even after the conviction, down from 37 percent beforehand. Without Lula on the ballot, conservative candidate Jair Bolsonaro would receive 17 percent of the vote, while leftist environmentalist candidate Marina Silva would receive 15 percent. Boulos, meanwhile, received 0 percent of the vote both with and without Lula on the ballot.

Lula’s popularity is not a product of Brazilians doubting the veracity of the allegations against him. 54 percent of Brazilians said that they believe his prison sentence was “fair,” while 40 percent said it was unjust.

Whether Lula’s socialist Workers’ Party (PT) will participate in the election without him on the ballot remains to be seen. Party leaders insisted last year that there was no “plan B” in the event that he went to prison. Lula reportedly left lawmaker Gleisi Hoffmann as the de facto head of the party in his absence, while some voices have called for the party to place former Sao Paulo Mayor Fernando Haddad on the ballot instead of Lula.

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