Operation Sisamnes: From a Lawyer’s Murder to the Largest Corruption Scandal in Brazil’s Superior Court of Justice
By HotspotNews-December 25, 2025
Brazil is witnessing one of the most serious crises in its judicial history. Operation Sisamnes, led by the Federal Police (PF) under the supervision of Supreme Federal Court (STF) Justice Cristiano Zanin, has uncovered a structured and highly sophisticated scheme involving the sale of judicial decisionsat the Superior Court of Justice (STJ)1– the court meant to be the ultimate guardian of legality in the country. Named after the ancient Persian judge Sisamnes, who was flayed alive for corruption, the operation exposes a “parallel market of influence” that moved millions in bribes, involving court staff, lobbyists, lawyers, and businessmen.
The Trigger: A Murder That Opened Pandora’s Box
It all began in December 2023 in Cuiabá, Mato Grosso. Lawyer **Roberto Zampieri**, known for handling major judicial recoveries in the agribusiness sector, was gunned down outside his office. Initially treated as an ordinary crime, the case took a dramatic turn when the Federal Police seized the victim’s phone. Encrypted messages revealed explicit negotiations of bribes to influence court decisions – not only in Mato Grosso state courts, but with direct references to STJ staff and ministerial cabinets.
Zampieri exchanged messages with lobbyist **Andreson de Oliveira Gonçalves**, dubbed the “lobbyist of the courts,” discussing sums such as “R$20 million to invest up there” – a clear euphemism for payments directed at the STJ. The conversations exposed early access to confidential draft rulings, manipulation of billion-real cases, and the use of fake legal contracts to launder money.
Launch and Early Phases (2024)
On November 26, 2024, the PF launched the **first phase** of Operation Sisamnes, authorized by Justice Cristiano Zanin. Andreson Gonçalves was placed in preventive custody, and search warrants targeted addresses linked to STJ staff. The operation identified three core groups: court officials and advisors, intermediaries (lobbyists and lawyers), and paying clients (primarily from agribusiness).
Just weeks later, on December 20, 2024, the second phase focused on money laundering derived from the sale of rulings, with additional searches in Mato Grosso.
The Explosive Phases of 2025: The Scheme Branches Out
Throughout 2025, the operation has accumulated more than ten phases, revealing the full depth of the corruption:
– March 2025 (3rd and 4th phases): Investigation into obstruction of justice and leaks of confidential STJ information aimed at derailing police operations. An underground surveillance network was dismantled.
– May 2025 (5th phase, May 13): Searches across three states targeting a money-laundering network, with the freezing of R$20 million in assets.
– May 2025 (7th phase, May 28): Five preventive arrests targeting the masterminds behind Zampieri’s murder. A criminal group involving active-duty and reserve military personnel was exposed, offering espionage and contract killings – complete with a “price list” that even included surveillance of STF ministers (R$250,000 per target).
– May 2025 (8th phase, May 29): Removal of a judge, freezing of R$30 million, and searches in Mato Grosso linked to corruption in the state court (TJ-MT) connected to the STJ scheme.
– June 2025: Arrest of the mayor of Palmas (TO), Eduardo Siqueira Campos, for systematically leaking confidential information.
– October/November 2025: Federal Police reports (including a 426-page document) described the scheme as the “most sophisticated and complex” ever seen in the Brazilian judiciary, with privileged access to ministers’ draft rulings. Evidence pointed to cabinets of ministers **Isabel Gallotti, Nancy Andrighi, Og Fernandes, Marco Aurélio Buzzi**, and others – advisors such as Daimler Campos, Márcio Toledo Pinto, and Rodrigo Falcão were suspended or dismissed. Suspicious payments to relatives and private jet loans emerged as additional bribery methods.
– December 2025: New actions targeting relatives of suspended state judges in Mato Grosso. Journalists like Malu Gaspar have warned that the investigation is “making a lot of people nervous” and could lead to further operations.
The Current Picture: Impunity for the Untouchables?
Despite dozens of arrests, suspensions, and dismissals, **no STJ minister has been formally charged**. Their privileged jurisdiction (foro privilegiado) shields them, with the inquiry handled at the STF level. However, the PF and the Attorney General’s Office (PGR) describe a clear pattern of hierarchical organized crime, with tentacles reaching deep into agribusiness (companies such as Fource Consultoria and Bom Jesus Agropecuária cited in billion-real frauds).
This scandal does not exist in isolation. It exposes a systemic crisis in the Brazilian judiciary, where political activism at the STF coexists with endemic corruption in superior courts. While ideological rulings censor social media and target political opponents, schemes like Sisamnes thrive in the shadows, eroding public trust in justice.
For conservatives who have always stood for equal law and order, this case is emblematic. We cannot accept a judiciary that protects its own while persecuting ordinary citizens. Operation Sisamnes represents a historic opportunity to clean house: demand full transparency, end privileged jurisdiction for common crimes, and impose exemplary punishment on all involved, regardless of position. If the thread keeps being pulled – and it is – the entire ball of yarn will unravel.
Brazil can no longer tolerate a justice system divided by caste. It is time to dismantle the judicial mafia and return power to the people.