Two Brazilian lawyers tried to manipulate a court's AI through hidden prompts and were fined 16,000 US dollars

A Brazilian labor court fined two lawyers about US$16,000 because, in a complaint they submitted, they embedded prompt injection instructions in white text on a white background, attempting to induce the court's AI tool to give the complaint only superficial processing, not question the document's contents and ignore other instructions. The judgment was shared on Platform X by Vladimir Aras, a professor at the University of Brasília. The court found that the injection ultimately had no effect and that the plaintiffs had already won by default because the defendants did not respond, but that the conduct harmed judicial dignity; given that the plaintiffs could not have modified the complaint themselves, full responsibility was borne by the two lawyers who signed it, who were fined 10% of the compensation amount involved in the case and reported to the state bar association and the internal affairs department of the regional labor court. The report also mentioned that a plaintiff had previously embedded a longer hidden prompt, which was discovered by a court clerk due to abnormal layout spacing and handled leniently because the person was not a practicing lawyer; in another case, a state judge was accused of using AI to directly generate a complete judgment, and a federal court ruled that the judge enjoyed judicial immunity.