Two lawyers ordered to pay S$5,000 each in personal costs for citing AI-generated fictitious cases

SINGAPORE: Two lawyers have been ordered to pay S$5,000 (US$3,900) each in personal costs for the misuse of artificial intelligence, after two fictitious cases were cited in closing submissions for a civil case.

The lead lawyer for the defendants had brought in another solicitor to assist in the research and drafting of the submissions. The second lawyer, in turn, said the initial research and drafting were done by a paralegal who has since left his firm and said he was unaware if any AI tools had been used.

The two lawyers offered to jointly bear personal costs of S$1,500, but the judge found that this sum was "plainly inadequate" and ordered each man to pay S$5,000 instead for a total of S$10,000.

According to a judgment released on Friday (Mar 6), the case involves the executors of the estate of a man named Tan Thuan Teck, who launched suits to recover sums lent to the late Mr Tan's four brothers and their company.

The lawyer for the defendants, Mr Goh Peck San, was found to have cited two fictitious authorities in closing submissions. The two cases were discovered by lawyers for the claimants and highlighted in their reply submissions.

Justice S Mohan, who found that the claimants had made out their case, focused his judgment on the AI issue. He said generative AI is reshaping the legal profession in a manner that can be fairly described as "nothing less than a sea change".

"While the technological advances that (generative) AI has engendered are not in themselves unwelcome, its integration into legal practice demands a commensurate evolution in professional responsibility. The very standards and ethical foundations of the profession depend on it," he said.

"The responsibility that lies on the shoulders of every advocate and solicitor utilising Gen AI has been repeatedly underscored in both the professional guidelines governing legal practice, and in judicial authorities. It is again re-emphasised in this judgment."

WHAT HAPPENED

The lawyer for the defendants, Mr Goh, engaged another solicitor, Mr Amarjit Singh Sidhu, to assist him in carrying out the research and drafting of the closing submissions.

On Aug 4, 2025, the claimants flagged the issue of the two fictitious cases to the court, named as Case A and Case B in the judgment.

While the neutral citation and name ascribed to Case A corresponded to real cases, the neutral citation belonged to an entirely different case. When put together, Case A with that name and that neutral citation did not exist.

Case B had an entirely fictitious name and neutral citation.

After these allegations, the court registry directed Mr Goh to respond. Eventually, he acknowledged the allegations and explained that the fictitious authorities had been provided by a fellow solicitor, without naming him at first.

Mr Goh said he was unaware of which AI tool had been used, expressing his regret and seeking the court's indulgence.

On the court's further questioning, Mr Goh said Mr Singh had been instructed to assist in the research and drafting of the submissions. In a letter, Mr Singh said the initial research for and draft of the closing submissions were prepared by an unidentified paralegal who had since left the firm.

He said he was unaware whether any AI tools had been used by the paralegal, but said he had reviewed the draft submissions and cases before transmitting them to Mr Goh.

Mr Singh conceded that he had overlooked the fictitious authorities. He later realised that the two cases he had sent to Mr Goh were not on point for the submissions made and informed Mr Goh that another case could not be located on LawNet and should be removed.

However, he forgot to inform Mr Goh that the two cases he had sent were not on point. Mr Singh apologised to the court and to Mr Goh and said his firm maintains an internal database containing authorities that support the legal principles set out in the submissions.

When asked to file submissions on costs for the fictitious authorities issue, Mr Goh said it had not occurred to him that Mr Singh might have used "non-traditional research tools" and was unaware that ChatGPT was a tool that could be used for legal research.

Because of time pressures and his workload, he had not verified the existence of the fictitious authorities. He had texted Mr Singh saying he was unable to locate certain cited authorities online.

In response, Mr Singh acknowledged via email that he too was unable to locate those authorities and advised Mr Goh not to rely on them.

Mr Singh admitted to providing the fictitious authorities. He said he had read the draft submissions twice before sending them on to Mr Goh, making only minor grammatical and typographical edits.

He confessed that he had "honestly overlooked" the fake cases and said the former paralegal who had provided them left the law firm in July 2025 and was uncontactable.

Mr Singh enclosed copies of email correspondence and WhatsApp messages requesting responses to the court's questions from the former paralegal. These went unanswered.

Mr Singh stated that he had previously instructed all staff in his law firm not to use ChatGPT or any other AI tool for work. He proposed a sum of S$1,500 for personal costs and offered to bear Mr Goh's share, asking that the matter be dealt with privately and not be reflected in a court order.

"TROUBLING ISSUE"

Justice Mohan said the troubling issue of counsel relying on AI-generated case authorities, without verification of their existence or accuracy, is attracting mounting concern in a number of jurisdictions.

The first reported case in Singapore addressing the citation of fictitious authorities was the case of Tajudin Gulam Rasul v Suriaya Haja Mohideen. In that case, the lawyer was ordered to pay S$800 in personal costs.

In less than a year after Tajudin was decided, more such cases have emerged, noted Justice Mohan.

"In my view, this phenomenon, if left unchecked, poses a serious threat to the administration of justice in Singapore, which relies heavily on lawyers to 'ensure that the evidence and arguments adduced before the court are skilfully, accurately and fairly presented'," he said, quoting from a previous case.

"The provision of fictitious authorities to the court wastes precious judicial time and resources at best, if the error is discovered in time. At worst, it may lead to an erroneous decision made in mistaken reliance on such fictitious authorities, resulting not only in potential embarrassment but more importantly, a potential miscarriage of justice," said Justice Mohan.

While clarifying that there is no inherent objection in using AI tools per se, such tools can "only ever play the part of the handmaiden".

"The fundamental point remains that lawyers bear ultimate responsibility for ensuring that all materials placed before the court – including case authorities – are, without exception, true and accurate, and crucially, verified by them to be so," he said.

The citation of fictitious cases constitutes sanctionable misconduct, said the judge. He found that Mr Goh's conduct was "clearly improper" as he failed to exercise due care and diligence in verifying the existence of the fictitious cases.

Justice Mohan said it ought to have been obvious to any competent solicitor that the bundle of authorities accompanying the submissions was incomplete.

"It should, and must, have been plainly evident to Mr Goh that Case A and Case B were not included in the bundle of authorities that was to accompany the closing submissions – a reasonably diligent solicitor would have picked up on this as a potential red flag," he said.

He said the fact that Mr Goh took no steps to address this "glaring omission" is a clear indication that his conduct fell short of that expected of an officer of the court.

"The proper and expected course of action would have been for Mr Goh to spend the time to track down and verify the existence of the missing authorities," said Justice Mohan.

"If the missing authorities could not be found, Mr Goh should have removed all references to them from the submissions altogether and to replace those references with actual cases on the point (verified to exist), and for those cases to be included in the bundle of authorities – these are not extraordinary steps that the court expects from counsel, but basic ones."

He also found that Mr Singh's role and conduct were improper and said Mr Singh ought to have recognised that a paralegal is not qualified to prepare written submissions independently, and that proper supervision and the verification of all authorities were ultimately his responsibility.

"Finally, I found it extraordinary that between Mr Goh and Mr (Singh), the issue fell between two stools and neither solicitor took the time or trouble of actually verifying the existence and veracity of the fictitious authorities," said Justice Mohan.

This was especially so for Case B, which, if searched online or using a research tool, would not have turned up an existing case.

Although it was plainly evident that an AI tool had most likely been employed, resulting in a hallucination, neither Mr Goh nor Mr Singh could shed any light on whether AI had been used.

"SHEER LACK OF DILIGENCE"

This demonstrated a "sheer lack of diligence displayed", said the judge. The fact that the fictitious cases were included without being picked up by Mr Singh, with no apparent inkling whether any AI tools had been used by the paralegal, indicates a "lax system of control and supervision", said Justice Mohan.

As for the lawyers' proposal to share the costs, Justice Mohan said responsibility must lie with both solicitors individually.

Mr Singh was primarily responsible for introducing the fictitious authorities, while Mr Goh "entirely failed" in his duty to verify them.

He disagreed with the proposed sum of S$1,500, saying it was insufficient to reflect the gravity of the matter.

Instead, he ordered a sum of S$5,000 each. The lawyers are also not to charge their clients for any time, costs or resources expended in dealing with the fictitious cases.

In closing, Justice Mohan offered caution to the Bar, saying he hoped that his judgment leaves no member of the Singapore Bar in any doubt over the critical importance of verifying the authenticity and accuracy of all materials submitted to the court, and in familiarising themselves with the rules and guidance on the proper use of Gen AI in the course of their work.

He added that such misconduct may result in disciplinary action against lawyers in future if appropriate, and solicitors cannot plead ignorance as the consequences for misusing AI tools are clearly spelt out.