Zhang v Chen, 2024 BCSC 285
·Supreme Court of British Columbia·CACosts order
The first reported Canadian case of AI-hallucinated citations: a Vancouver family lawyer cited two ChatGPT-invented cases in a notice of application, was ordered to pay costs personally, had her other files reviewed, and faced a Law Society of British Columbia investigation.
- Court
- Supreme Court of British Columbia
- Date
- 2024-02-20
- Who used the AI
- Not recorded
- AI tool
- ChatGPT
- Conduct
- Counsel in a family-law matter cited two non-existent cases generated by ChatGPT in a notice of application; the fabrications were discovered by opposing counsel.
- Outcome
- Costs order
- Penalty
- No monetary penalty recorded
- Regulatory outcome
- Law Society of British Columbia: LSBC investigation into the lawyer's conduct followed the judgment; the court ordered costs against the lawyer personally and a review of her other court files.
- Status
- Verified against listed sources
- Last checked
- Not separately recorded
What was fabricated or misused
- M.M. v. A.M., 2019 BCSC 2060 — cited in the notice of application as granting a mother leave to travel with a child to India; no such case exists
- B.S. v. S.S., 2017 BCSC 2162 — cited as granting a mother leave to travel with a child to China; no such case exists
What the court said
“The notice of application was formally filed on December 6, 2023. The Legal Basis section of the notice contained only two cases. These cases are at the center of the controversy before me, as they were discovered to be non-existent.”
“I accept her evidence that she was naive about the risks of using ChatGPT and that she took steps to have the error corrected. Though her legal education is extensive, there is a significant difference between academics and lawyering. I do not find that she had the intention to deceive or misdirect.”
“Additional effort and expense were incurred because of Ms. Ke’s insertion of the fake cases. This additional effort and expense is to be borne personally by Ms. Ke.”
“As this case has unfortunately made clear, generative AI is still no substitute for the professional expertise that the justice system requires of lawyers. Competence in the selection and use of any technology tools, including those powered by AI, is critical. The integrity of the justice system requires no less.”
Timeline
- Notice of application filed; its Legal Basis section cites only the two non-existent cases.
- Opposing counsel reports the cases cannot be located and asks for copies.
- Ms. Ke contacts the Law Society of British Columbia about the error.
- Scheduled hearing date; the fake authorities are withdrawn before the application is heard.
- Masuhara J rules on the parenting application and reserves the question of costs.
- Reasons on costs: special costs refused; wasted costs ordered personally against counsel under Rule 16-1(30); review of all her files ordered.
Why this case matters
Zhang v Chen is the first reported Canadian decision on AI-invented authorities and it set the tone for the Canadian records that followed it, including Ko v Li in Ontario. Masuhara J refused special costs because he found no intent to deceive, but still made the lawyer personally liable for the wasted hearing time under Rule 16-1(30) of the Supreme Court Family Rules, ordered her to review every file before the court for other AI-generated citations, and told her to disclose AI-generated content in future filings. The judgment also records that the Law Society of British Columbia had warned the profession about ChatGPT twice in 2023, which the court held against counsel without treating the failure as reprehensible.
Practice note
Every authority in a notice of application must be opened in CanLII or the court's own database and read before filing; a citation that cannot be found is withdrawn at once, and opposing counsel is told immediately rather than after repeated requests. Where a Law Society has issued generative-AI guidance, the court will expect counsel to know it. Disclosing AI-generated content in materials handed up to a BC court is now the prudent course this judgment names.
Primary sources for this incident
Related regulation records for this incident
Similar incidents on the record
- Ko v. Li, 2025 ONSC 2965; 2025 ONSC 67852025-12-04 · Ontario Superior Court of Justice · Regulatory referralIn Ontario, lawyer Jisuh Lee filed a ChatGPT-fabricated factum, then admitted she had lied about authorship after initially blaming others. Justice Myers referred a criminal-contempt prosecution to Ontario's Attorney Ge…
- State ex rel. Oklahoma Bar Association v. Reeves, 2026 OK 372026-05-27 · Supreme Court of Oklahoma · WarningThe Oklahoma Supreme Court publicly reprimanded attorney Matthew Reeves under reciprocal-discipline rules after he admitted using ChatGPT to fabricate five citations in federal filings in Johnson v. Dunn — conduct alrea…
- State v. Coleman, 2026-Ohio-965 (Ohio Ct. App., 11th Dist.)2026-03-20 · Ohio Court of Appeals, Eleventh Appellate District · SanctionsAn Ohio appellate court fined a criminal-appeal attorney $2,000, removed him as counsel, struck his reopening application, and referred him to the Ohio Office of Disciplinary Counsel after his staff's ChatGPT use produc…
- Tan Hai Peng Micheal and another v Tan Cheong Joo and another [2026] SGHC 492026-03-06 · General Division of the High Court of the Republic of Singapore · Costs orderIn this Singapore High Court (General Division) costs ruling, S Mohan J made personal costs orders of S$5,000 each against the counsel on record and his supervising solicitor for filing fictitious AI-generated citations…
Cite this record
SafeLegalAI Global Legal AI Incident Tracker, “Zhang v Chen, 2024 BCSC 285”, safelegalai.com/tracker/zhang-v-chen (accessed 2026-09-16). Data: CC BY 4.0.