[Invest&Law]This Ruling Does Not Exist

Published 01 Oct.2025 09:23(KST)

Five Cited Rulings in Brief
First Detection of Fake Cases Created by AI Hallucinations
"Did the Attorney Not Even Verify?"

An incident has occurred in South Korea where a legal brief citing fabricated case precedents generated by generative artificial intelligence (AI) was submitted to a court and subsequently detected. Concerns are being raised that this could undermine not only attorney ethics but also the very foundation of the judicial system.

Recently, a criminal court in a local jurisdiction checked five rulings cited in a brief submitted by Attorney A through the court’s electronic system and found that the referenced cases did not exist. Before the next hearing, Attorney A submitted a statement withdrawing the problematic precedents. However, during the trial, the court inquired about the sources, and Attorney A admitted to using AI. The attorney was discovered to have submitted non-existent, fake precedents created by AI hallucinations without verifying their authenticity.

"Fraudulent Litigation by Deceiving the Court"

This is the first time such an incident has been reported in a South Korean court. A judge from a metropolitan court remarked, "We now live in a world where AI can generate plausible but fake legal principles in seconds with just a single question," and added, "It is deeply troubling that an attorney, a legal expert, would submit a brief without proper verification." A partner attorney at a mid-sized law firm commented, "If the attorney acted knowingly, this constitutes litigation fraud by deceiving the court."

Such incidents, which have occurred overseas, are no longer just someone else’s problem. In the legal industry, some say it feels like "fighting against AI," as the side effects of routine AI use are disrupting work. Attorney B reported that more clients are now asking, "I heard there’s a ruling like this," based on incorrect information obtained from AI, unnecessarily prolonging consultation times. Attorney C shared that after repeatedly searching for a Supreme Court precedent cited in an opposing brief, they ultimately confirmed that the precedent did not exist.

Police Citing False Legal Principles?

It has also been confirmed that the police made a non-prosecution decision based on legal principles that did not exist in the actual ruling (Refer to the exclusive report by Digital Law News on September 26, 2025, "Police Decide Not to Prosecute Child Abuse Case Based on Fake Precedent"). In a child abuse complaint case, the police issued a non-prosecution decision, citing Supreme Court and Seoul Northern District Court rulings, but the cited legal principles were not present in the actual decisions. The quoted text in the non-prosecution decision could not be found anywhere in the rulings. Experts suggest that investigative agencies may have failed to properly verify hallucinated information generated by AI.

Court Administration Office "Considering Countermeasures"

While AI can be helpful for self-represented litigants, there are concerns that non-experts may accept false information as fact, highlighting the need for discussions on the scope of AI use and related ethics. Judge D stated, "With more briefs written using AI in cases without attorneys, it now takes longer to review documents to check for incorrect legal provisions or principles than before."

The Court Administration Office is also aware that the submission of briefs containing non-existent precedents due to AI hallucinations is increasing. An official from the office said, "Although we have not yet created relevant guidelines, we recognize the need to consider countermeasures."