A trainee pastes the client's statement of claim into a free AI tool. That same day, the other side files an audio recording in which your client "confesses". Both are evidence problems.
Safe use of AI according to the OAB (Brazilian Bar Association), what the courts have decided on fabricated case law and hidden prompts, and how forensic examination handles synthetic voice, image and video.
AI came into the law firm through the back door: the trainee in a hurry, the free tool, the client's data in the prompt. The OAB recommended care with confidentiality and checking every precedent. Courts have fined lawyers for fabricated case law, and the STJ (Brazil's Superior Court of Justice) has sanctioned filings with hidden prompts aimed at AI.
On the other side of the table, AI has become the object of evidence. Cloned voices, doctored images, synthetic video. It has also become a source of evidence: AI-generated reports filed as if they were expert examinations. Online AI detectors do not solve this, and the STJ has already excluded from the record an AI report with no human validation.
The course covers both sides: the firm's own use of the tool, and the forensic examination of the material that comes from the other side.
Pick as many courses as you like: they are kept and arrive ticked on the registration form.
A person saw their own voice, in a recording they never made, tell a false story on social media. The examination analysed the synthesis artefacts, with forensic phonetics, and the file itself. The expert report showed that the voice was synthetic and preserved the posts so that authorship could be investigated.
An image was circulating as an accusation against a mayor, who appeared in a place where he should not have been. The authenticity examination of the file and its content showed that the image was a montage.
For more than a year, a shopkeeper had been paying a high fee for advances on his card receivables, contracted by phone. The examination compared the voice in the recording with the shopkeeper's reference samples and with the voice of the employee who took part in the call. The voice was not the shopkeeper's and showed similarity to the employee's. Not every fake voice needs AI.
An associate hands the partner a draft prepared with the help of AI, on the eve of the deadline. Three of the precedents do not exist, and the PDF contains, in its text layer, a paragraph that does not appear on the page. Ten minutes of checking avoid the fine.
In groups of three, with the fictitious description of a WhatsApp audio message in which a partner "authorises" a transfer, participants choose in 10 minutes the five most useful questions from the Question bank and what they would ask for to preserve the original.
Laws and rulings discussed
Federal Council of the OAB (Brazilian Bar Association), Recommendation 001/2024 (OAB Electronic Gazette of 14 November 2024) · CNJ (National Council of Justice), Resolution 615/2025, consolidated text with Resolution 674/2026 · CPC, arts. 77, 80, 81 and 422, § 1º (Brazilian Code of Civil Procedure) · TJSC (Santa Catarina State Court of Justice), news item of 18 February 2025 · TST (Brazil's Superior Labour Court), news item of 26 March 2026 · STJ (Brazil's Superior Court of Justice), news item of 18 October 2026 · STJ, news item of 20 October 2026 · CP, art. 147-B, sole paragraph (Brazilian Penal Code)
See also
Forensic Services in Media, Entertainment and Deepfakes → Forensic Phonetics and Voice Examination → Audiovisual Forensics: Video and Image → Digital Questioned Document Examination → See all courses →