South Korea's Top Tax Accountant Exam Scorer Confesses to Cheating With Generative AI

Han Won-seok, who topped the 63rd edition of the exam, said in a video posted on the YouTube channel of his lawyer, Lee Don-ho, that he photographed the questions with a miniature camera, sent them to an AI tool and checked the answers on a smartphone. He said his top score "was not the result of fair effort." Appearing in a face mask, he said he had submitted a written confession to Seoul police.

The admission matters because the exam's own safeguards did not catch him. The Human Resources Development Service of Korea, which runs the test, had earlier said it found no concrete evidence of wrongdoing, and the four proctors who supervised Han across both stages reported nothing suspicious, The Korea Times reported. The confession came days before South Korea's national college entrance exam on Thursday, where officials are already worried about AI-assisted cheating.

Han answered 159 of 160 questions correctly in the first stage in April, scoring 397.5 out of 400, and scored 663 out of 800 in the second stage three months later, according to The Korea Times. Scrutiny began after he posted his results on an online community for tax accountants and described passing through self-study. He initially denied cheating, at one point arguing that guessing was a skill, the Seoul Economic Daily reported.

He has also admitted using the same method in the first round of the recent certified public accountant exam. Neither Han nor his lawyer has named the AI tool involved, and Han declined to describe the method in more detail, saying he did not want others to copy it. Online speculation that he had worn AI smart glasses was wrong, according to The Korea Times.

The Seoul Metropolitan Police Agency has opened a formal investigation and promised "swift and rigorous" fact-finding, the paper reported. Some of the devices Han used have been destroyed. He plans to hand over the rest and filed a list of the evidence with his confession, according to the Seoul Economic Daily. Lee said the methods would be explained to investigators and, if asked, to the exam administrators.

Han said he turned to cheating after struggling to keep his own business going once he left a corporate job, a strain he blamed on rising costs linked to the war in Ukraine, and because he was anxious about how long it would take to qualify. "I wanted to make money, and I hated seeing myself disappoint my parents after leaving a good job," he said, as quoted by The Korea Times.

The college entrance exam is the next test of the system. The prime minister's office said the government would prepare thoroughly and oversee the process closely to keep the exam fair and stable, Reuters reported, and Seoul education officials have been training staff to detect smart glasses. Han said he would help police prevent cheating in future exams, including that one.