Fábio Luís Lula da Silva used his father’s presidency to influence Brazil’s Health Ministry decisions on behalf of a lobbyist seeking to commercialize medical marijuana. The Brazilian Supreme Federal Tribunal authorized federal police to investigate that allegation on Wednesday, at the Federal Police’s own request. The subject is the sitting president’s son. The alleged wrong is leveraging the presidency to serve a lobbyist’s commercial interests inside a ministry that answers to the president. The investigation is now on the official record.

The strongest version of what the STF did is straightforward: it acted like a court. Justice André Mendonça approved the investigation after the Federal Police presented evidence it believed warranted formal inquiry. The STF’s original jurisdiction over matters touching the executive branch, grounded in Article 102 of Brazil’s 1988 Constitution — the document written to prevent exactly the kind of executive impunity the military dictatorship had perfected — is the legal instrument under which the Court authorized the probe. The constitutional architecture is designed for this: the judiciary’s capacity to investigate the family of the person who commands the executive. A court that refuses to authorize an investigation into the president’s son because of the political consequences is a court that has surrendered its function. The STF did not surrender.

The investigation proceeds under Brazil’s anti-corruption framework — Lei Anticorrupção (Law 12,846 of 2013), the statute governing acts of corruption against public administration, including the use of public function to obtain undue advantage for third parties. The legal architecture is sound. The question is whether it will hold under the political pressure it is now entering.

The thread investigators followed leads from Antônio Carlos Camilo Antunes, a lobbyist who has been in jail since September accused of operating a fraud scheme that targeted Brazilian pensioners. The investigation into Lulinha is an offshoot of that broader probe — investigators traced the connection and arrived at the presidential family. The scandal has already consumed Brazil’s social security minister and the head of the National Social Security Institute. Now it reaches the first family itself.

Lula, fresh off blocking US officials’ visas over alleged election interference, appeared on the Inteligência Ltda. podcast and delivered the only statement available to a president who cannot shield his son without destroying his campaign: “If my son is accused of something, he will receive the same treatment as anyone else. He will have no privileges.” He said he would never ask police or a judge to intervene and that his son would have to prove his innocence through the legal process.

The statement was calibrated to sound principled. What it actually revealed was the constraint Lula is operating under: he cannot protect his son without demolishing the political identity on which his presidency was rebuilt. Lula has spent the last weeks projecting sovereign defiance — recalling Brazil’s ambassador to Argentina after Javier Milei endorsed Flávio Bolsonaro for São Paulo governor, denying visas to American officials he accused of trying to undermine the October vote. The threat he was defending against was external. Now it is domestic, and it lives inside his own family.

The timing is devastating. Brazil’s presidential campaign enters its most intense stretch ahead of the October election, and Lula is seeking another term with a corruption investigation targeting his son now on the official record. No charges have been filed against Lulinha. But the STF’s authorization is not a clerical step. It is the opening of a federal police investigation that will run directly through the most sensitive weeks of the electoral calendar. For a president who lost one term to corruption’s political fallout, who spent years in prison before his convictions were annulled, and who rebuilt his career on the claim that he had been wronged — a family-linked corruption probe during a re-election bid is not merely embarrassing. It threatens the foundation on which his return to power was built.

The investigation may clear Lulinha. What it has already accomplished is handing Lula’s opponents the precise argument they needed at the precise moment they needed it: that the Workers’ Party presidency, once again, cannot separate public power from private gain.