A Canadian lawyer has been suspended for six months after a judge uncovered ChatGPT-generated fake legal citations in a court hearing.
The Law Society of Ontario’s discipline tribunal suspended Mary Hyun-Sook Lee, who practises as Jisuh Lee, after finding she committed professional misconduct by relying on AI-generated case law that was either fabricated or irrelevant in a family and estate law matter, the National Post reported.
The tribunal ordered Lee to complete remedial measures during her suspension and pay C$10,000 in costs after concluding that she failed to properly represent her client and deliberately misled the court through her submissions.
The disciplinary action follows a hearing in Ontario Superior Court last year, where Justice Fred Myers questioned the validity of several cases cited in Lee’s written submissions. When asked to produce copies of the authorities she relied on, Lee was unable to provide them, prompting the judge to search for the cases himself.
According to the court’s findings, some of the cited decisions could not be found in any legal database, while others were unrelated to the issues before the court or contradicted the arguments Lee advanced. In one instance, a case cited as supporting the removal of an estate trustee was found to have reached the opposite conclusion.
Justice Myers questioned whether artificial intelligence had been used to prepare the material.
In his written reasons, he noted that Lee said her office did not usually rely on such tools but that she would need to confirm with her clerk.
The tribunal found that Lee’s conduct fell below the standard expected of a lawyer, stating that she relied on a factum containing non-existent or irrelevant case law generated by an artificial intelligence tool and misled the court in doing so.
Toronto lawyer Tom Macintosh Zheng, who tracks AI use in legal practice and was cited by the outlet, said the case marks the first time a Canadian law society has suspended a lawyer for misusing artificial intelligence in court submissions, rather than issuing a reprimand.
Zheng added that the case highlights growing concerns within the profession about the risks posed by unverified AI-generated material. “There is increasing scrutiny on how lawyers use these tools, particularly where they affect the integrity of court proceedings,” he said.
The judge emphasised that lawyers have a fundamental duty to verify the authorities they present. He wrote that it should be self-evident that counsel must read and confirm the cases they cite and must not rely on authorities that do not exist or that support the opposite of their position.
Separate civil contempt proceedings against Lee remain ongoing. The court has appointed an amicus curiae, an independent lawyer who assists the court, citing procedural uncertainty, including Lee’s failure to retain legal counsel.
