Top scorer in South Korea tax exam admits cheating with AI and a hidden camera

The top scorer in South Korea's national tax accountant exam has confessed to cheating with generative artificial intelligence, photographing questions with a hidden microcamera and checking the answers on a smartphone, days before the country's most important exam of the year.

The candidate, identified only by the surname Han, ranked first in both rounds of the tax accountant qualification exam, held in April and July. On Sunday he apologised on the YouTube channel Attorney Lee Don-ho, speaking on camera while wearing a face mask, and said through his lawyer that he had submitted a written confession to Seoul police that morning.

His confession ends weeks of speculation about a result that many found impossible to believe. He scored 397.5 out of 400 points in the first round, with only one wrong answer out of 160 questions, a near-perfect score that had prompted accusations that he cheated using smart glasses, which he initially denied.

The Seoul metropolitan police agency confirmed it had received the confession, saying it had been submitted through the test taker's lawyer that morning and that the case had been assigned to investigators. What happens to Han now, and whether his qualification will be revoked, has not yet been decided.

A score too good to be true

The numbers were what gave him away. A score of 397.5 out of 400, with a single wrong answer in 160 questions, is a result so far beyond the norm that it invited suspicion from the moment it was published. In an exam designed to be punishingly difficult, where even the best-prepared candidates expect to lose marks, a near-perfect paper looks less like brilliance than like a clue.

Han initially denied the accusations, including the suggestion that he had used smart glasses during the exam. His confession, when it came, described a method that was simpler and harder to detect: he photographed the exam questions with a microcamera, sent the images to an AI tool, and checked the answers on a smartphone.

In his apology he was blunt about what he had done. He said he had cheated using electronic devices and generative AI, and that passing the exam with the top score was not the result of fair effort. It was a strikingly direct admission from a man who had, until that morning, been celebrated as the brightest new tax accountant in the country.

The method matters as much as the confession. A microcamera small enough to pass unnoticed, a phone and an AI tool capable of answering professional exam questions in real time add up to a system that traditional invigilation is not designed to catch.

A confession on camera

Han chose to confess in public, on a lawyer's YouTube channel, wearing a face mask. By going on camera, he put his own name to the cheating before the police or the exam authorities could announce it themselves.

The police confirmed the written confession had been received through his lawyer on Sunday morning. The investigation will now establish the details: how the equipment was brought into the exam hall, whether anyone else was involved, and whether the same method was used in both rounds of the exam.

The tax accountant qualification is a serious professional credential in South Korea, and passing it opens the door to a well-paid career. The cheating is not only a personal disgrace for Han, but a blow to the credibility of a qualification that employers and clients rely on.

There are also reports of potential cheating in the certified public accountant exam, which the presidential office has described as concerning. If AI-assisted cheating is spreading through professional exams, the problem is larger than one candidate and one exam.

A nation on edge before the big exam

The timing could hardly be worse. The scandal has broken days before South Korea's annual national college entrance exam this Thursday, a high-pressure event for which many students have spent much of their lives preparing.

The presidential office said on Sunday that it viewed the matter very seriously, and that because the college entrance exam is next week, it had been working hard to prepare countermeasures. The presidential chief of staff for policy was to convene an emergency meeting later in the afternoon to discuss the response.

Prime Minister Han Seong-sook acknowledged on Friday the public concerns over AI-assisted cheating. Her office said the government would prepare thoroughly in advance and closely oversee the process until the very end to ensure the college entrance exam is conducted fairly and stably.

The challenge facing the authorities is formidable. The college entrance exam involves hundreds of thousands of students in thousands of exam halls, and the tools Han used are cheap, small and widely available.

What the scandal has shown is that the technology has already arrived, and that the defences have not kept up. Whether Thursday's exam can be protected from the same methods will be the test of whether the system can adapt as fast as the cheats.