Top scorer in South Korea tax exam admits AI cheating

Top scorer in South Korea tax exam admits AI cheating

When Han Won-seok sat for South Korea’s state-administered tax accountant examination, he answered 159 out of 160 questions correctly on the first stage, missing only a single query. That solitary figure ignited a national reckoning on Nov 15 when the 34-year-old candidate admitted that his triumph was built entirely on a miniature camera, a smartphone, and generative artificial intelligence. The confession, delivered on his attorney Lee Don-Ho’s YouTube channel on Sunday, marks the first known case in which a person who successfully passed a state-administered examination acknowledged using such equipment to cheat.

The cheating method relied on a hidden rig: Han used a miniature camera to photograph exam questions as they appeared on the test paper, transmitted the images to an AI tool, and read the resulting answers on his smartphone. He confessed to using the identical setup on both the first and second rounds of the tax accountant evaluation. I cheated by taking pictures of the questions with a miniature camera, sending them to AI, and checking the answers on a smartphone, Han said in the video posted by his lawyer. In the first round in April, he missed only one out of 160 questions, earning 397.5 points out of a possible 400. He scored 192 and 190 in the two accounting subjects and 114 and 167 in the two tax law subjects in the second round. Following the online backlash that erupted after he shared his study story with local media on Nov 11, Han initially denied any wrongdoing before changing his mind after thinking about the feelings of the candidate who came second, and submitting a written confession to the Seoul Metropolitan Police Agency.

Proctors and metal detectors miss the gear

The scandal has exposed severe vulnerabilities in how South Korea secures its high-stakes testing halls. During the first and second rounds of the tax accountant examination, held in April and July, two proctors were stationed near Han, whose desk sat in the middle of the second row from the podium for the first round and the middle of the first row for the second round. Despite their close proximity, invigilators failed to detect the equipment, and no camera footage from the examination rooms captured him wearing the suspected devices.

The limitations of standard security screening were laid bare during an Oct 23 parliamentary audit of the Ministry of Science and ICT, where officials noted that conventional metal detectors struggle to flag miniature electronic components. The Human Resources Development Service of Korea (HRD Korea), which administers the exams under government mandate, stated that an initial review of proctor reports and grading data revealed no irregularities. The agency has since commissioned outside grading experts to review Han's second-round essay answer sheets, while announcing plans to expand its CCTV network from the current 529 cameras and deploy radio-wave detectors developed by the Korea Radio Promotion Association once field testing concludes.

HRD Korea administers state qualification tests for various government bodies, while the Certified Tax Accountant examination demands years of rigorous full-time study. Candidates face grueling multi-stage assessments, including multiple-choice aptitude tests and essay-based papers on tax law and accounting.

Personal pressures and statistical anomalies

In his public apology, Han pointed to personal and financial pressures as the catalyst for his deception. I started preparing for the exam in my early 30s and felt desperate, worrying about how long it would take me to pass, he explained, adding that little savings and a failed business venture, which suffered from rising costs following the Russia-Ukraine war, left him deeply anxious about his future. I wanted to make my parents proud again with a pass, even if I had to cheat to get it, he said, adding that he had only cheated to try and earn money and get a job that would make his parents proud of him again.

Those personal struggles translated into statistical anomalies that ultimately drew the attention of online commentators and testing experts. On the introduction to tax law section, where 74.21% of candidates failed to clear the minimum threshold and 16,856 test-takers averaged just 30.18 points out of 100, Han scored a perfect 100. Across the entire essay-based second round, his average reached 82.875 on a 100-point scale, sitting more than 33 points above the 49.75 passing cutoff. Critics also pointed to photographs of his study materials showing little wear and misspellings in his handwritten notes on key terms, discrepancies he initially dismissed before turning himself in.

Police investigation and official penalties

Upon receiving Han's written confession on the morning of Nov 15, the Seoul Metropolitan Police Agency immediately assigned the case to its Metropolitan Investigation Unit for a strict, expedited inquiry. We received a written confession through the test taker's lawyer this morning regarding cheating on the tax accountant exam, the agency announced. We assigned the case to the Metropolitan Investigation Unit immediately upon receipt and plan to investigate swiftly and strictly in accordance with procedure.

Administrative and regulatory bodies are moving in parallel with criminal investigators. The Ministry of Finance and Economy said it would move swiftly to suspend the validity of his certificate confirming that he had passed the examination. Under South Korean law, proven cheaters can have their examination results invalidated and face a five-year ban from taking the test, starting from the date the penalty is imposed. Following Han's confession, the Ministry of Employment and Labour and HRD Korea held an emergency meeting, and HRD Korea officials noted that because of the case, they need to consult the Ministry of Employment and Labour, the Ministry of Finance and the National Tax Service to establish a response protocol.

Presidential policy chief Ha Jun-kyung said new measures would be introduced to prevent cheating and warned that past crimes would be tracked down and apprehended to the very end.

Wider testing crisis and AI cheating cases

The fallout has widened far beyond the tax accountant certification, sparking nationwide anxiety over the integrity of professional licensing and academic evaluations across South Korea. Standardised national tests play an outsized role in career trajectories for South Koreans, making their results of great importance. Five others have already been caught using unauthorised equipment during state certification tests in 2026, and politicians have demanded immediate oversight of academic testing. The ruling Democratic Party of Korea called for a thorough police investigation and more active efforts to identify systemic loopholes in examination monitoring, while the main opposition People Power Party criticised the government for failing to keep pace with technological advances in AI.

The case is part of a series of AI-assisted cheating incidents in South Korea, where test-takers have recently been caught using AI glasses in university entrance exams and middle and high school tests. Last month, two college applicants were reported to have used AI glasses to try and cheat their entrance exams at two Seoul universities. Education ministry data also shows there were four cases of cheating through AI glasses at middle and high schools in the past 12 months.

Suspicion has also fallen on other unprecedented academic results recorded this year, including a candidate who achieved the first perfect score in the 19-year history of the Legal Education Eligibility Test, and a candidate who has said he will live-stream his reading-comprehension skills using questions from the College Scholastic Ability Test (CSAT), South Korea’s nationwide university entrance examination, scheduled for Nov 19. Meanwhile, the Blue House, or Cheong Wa Dae in Korean, stated it was closely monitoring the case and considering possible measures for other examinations, including the CSAT.

Han concluded his statement by offering direct apologies to his peers, practicing professionals, and test supervisors. I cheated in both the first and second rounds of the tax account exam by using electronic devices and generative AI, he noted in the video published on Sunday, adding, It seems that because of me, other successful candidates are being suspected. To the test-takers who prepared diligently for a long time, and to those who passed the exams fairly, I once again offer my sincere apology. My cheating caused great disappointment and emptiness for test-takers. I also damaged trust in the fairness of the exam, he said, promising to submit the remaining materials, devices, and other evidence to investigators as they are.