Brazilian Labor Court Fines Attorneys 16,000 Dollars Over Invisible Prompt Injection in Legal Filing
A Brazilian regional labor court sanctioned two attorneys after discovering hidden text engineered to manipulate the judiciary's automated artificial intelligence assistant, Tom's Hardware reported. Judicial staff identified the covert instruction within an initial complaint processed through the court's digital analysis tool, known as Galileu, Mezha.net reported. The lawyers formatted the instruction using white font against a white document background, concealing the phrasing from human readers during standard visual review, Tom's Hardware noted. Court personnel uncovered the hidden command after adjusting background document colors during automated file processing.
Galileu Tool Manipulation and Prompt Injection Mechanics
Upon altering the typography color, judicial officers revealed an explicit directive instructing the automated system to conduct superficial review and avoid challenging attached evidentiary documents, Mezha.net reported. The judicial ruling cited the machine-translated text commanding the artificial intelligence to respond superficially and accept the petition without contesting submitted records. The presiding labor judge classified the technical maneuver as prompt injection, defining it as the deliberate insertion of concealed instructions intended to distort algorithmic reasoning in favor of the submitting party. The court condemned the deceptive submission as an act offensive to the dignity of justice, Tom's Hardware reported.
The court fined the two law firms 10% of the claim's value, where the underlying claim was R$842,000, making the fine approximately $16,000, according to JetStream Security.
The court based its sanction on procedural good-faith obligations in Article 5 and Article 77 of the Brazilian Civil Procedure Code, ruling that the conduct constituted an act undermining the dignity of justice, according to JetStream Security.
The artificial intelligence tool known as Galileu was initially built by the Regional Labor Court of the 4th Region before being deployed nationwide by the Superior Council of Labor Justice, according to Cescon Barrieu.
Default Judgment Ruling and Financial Penalties
Because the opposing defendant failed to submit a timely response to the allegations, the plaintiff secured a default judgment, rendering the manipulative prompt completely unnecessary, Tom's Hardware reported. The court concluded that the individual claimant possessed neither the legal knowledge nor the technical access required to engineer the document manipulation, Mezha.net noted. Consequently, the presiding judge placed exclusive legal responsibility upon the two signing attorneys, imposing a penalty of ten percent of the total case valuation, equivalent to roughly 16,000 dollars, Tom's Hardware reported. Judicial authorities also reported the practitioners to the regional legal guild alongside the court's internal oversight bureau.
Institutional Oversight and Professional Disciplinary Referrals
Law professor Vladimir Aras of the University of Brazil publicized the judicial ruling on social media platform X, Mezha.net reported. The incident underscores emerging institutional challenges as legal jurisdictions incorporate automated language models into judicial document intake and case analysis workflows, Tom's Hardware noted. Judicial administrators previously encountered prompt manipulation attempts in separate proceedings, including an instance where document spacing anomalies alerted clerks to inserted instructions. In another legal matter, a state judge faced a federal lawsuit for allegedly delegating judicial decisions to automated software, though courts recognized judicial immunity, Tom's Hardware reported.