A lawyer in British Colombia, Canada, was reprimanded and ordered personally to cover the costs of her opposing counsel for citing fake legal cases invented by ChatGPT in a divorce case.

Chong Ke was hauled over the coals by Justice David Masuhara for including two AI 'hallucinations' generated by ChatGPT in an application filed in December 2023 on behalf of businessman Wei Chen in his divorce proceedings with his ex-wife Nina Zhang. 

The non-existent cases generated by ChatGPT would have provided compelling precedent for the divorced father to take his children to China. 

Ke claimed not to know if the risks of using ChatGPT - an acknowledgement accepted by the judge, who said he did not think Ke intended to deceive the court. 'I did not intend to generate or refer to fictitious cases in this matter. That is clearly wrong and not something I would knowingly do,' Ke wrote in her deposition. 

The incident raised questions about lawyers' apparent attempts to use generative AI as a substitute for their professional expertise, and to cut their own costs. 

'As this case has unfortunately made clear, generative AI is still no substitute for the professional expertise that the justice system requires of lawyers,' Masuhara wrote in a 'final comment' appended to his ruling.