Actor Kim Soo-hyun has filed a lawsuit against the bereaved family of the late Kim Sae-ron and the YouTube channel 'Garosero Research Institute.' Meanwhile, the company that analyzed the mobile messages he presented as evidence has released the analysis results.
Recently, the statement analysis center TruBaum published the results of its analysis on the consistency of messages related to Kim Soo-hyun using the 'author identification' technique. TruBaum is a professional expert service institution that scientifically assists in the establishment of judicial justice by objectively and neutrally analyzing the authenticity of statements based on theories and research findings in psychological science. The 'author identification' technique they use is a linguistically based method that statistically reviews whether documents from different points in time were written by the same individual, unlike typical statement reliability analyses.
TruBaum quantitatively measured the frequency of parts of speech in each message, calculated the average usage frequency based on 18 linguistic elements, and estimated the characteristics of the message author through personal language patterns. As a result, there were no statistically significant differences among messages from 2018 to 2025, leading to the conclusion that they were likely written by the same individual.
In contrast, the messages from 2016 showed significant differences when compared to those from 2018 and 2025. Statistically, there is a high possibility that the messages were not written by the same person, with a 95% confidence level between the 2016 and 2025 messages, and a 92% confidence level between the messages from 2016 and 2018. In particular, the analysis found that the probability of the 2016 messages being written by the same individual is only 8%.
The messages from 2016 are materials released by the 'Garosero Research Institute,' and the analysis through the 'author identification' technique raised the possibility of manipulation. However, while the 'author identification' technique is widely used academically overseas, it is still a relatively unfamiliar analysis method in South Korea, so the reliability of this analysis in court will depend on future judicial judgments.
Previously, the bereaved family of the late Kim Sae-ron claimed that Kim Sae-ron had been in a relationship since 2015 when she was 15 years old and Kim Soo-hyun was 27, based on the deceased's messages and letters. Kim Soo-hyun countered that they started dating after she became an adult, but messages exchanged in 2016 and 2018, such as 'When can I hold you and fall asleep?' were made public, reigniting controversy.
In response, Kim Soo-hyun held a press conference and stated, "The bereaved family is framing me as a pedophile and grooming a minor. However, I was not the person who exchanged messages with the deceased on KakaoTalk in 2016 and 2018; it was someone else. To prove this fact, I submitted the KakaoTalk messages from 2016, 2018, and this year that I exchanged with acquaintances to an organization that conducts scientific analyses. That organization concluded that the individual was not the same person as in 2016 and 2018," adding, "The bereaved family has fabricated the KakaoTalk messages. Not everything that is untrue becomes true. Just as I have gone through verification procedures, I will ensure a thorough investigation of all evidence presented by the bereaved family through investigative agencies."
Following Kim Soo-hyun's press conference, public interest focused on the credibility and authority of the center where he underwent verification. Attention was drawn to the statement analysis center TruBaum and its representative Kim Mi-young, a doctor of criminal psychology and a specialist advisor to the prosecution office, who has also worked as an expert in sexual violence at the Supreme Public Prosecutors' Office. With TruBaum being a private company rather than a national institution, and the part where Kim Mi-young predicted the messages of Jo Joo-bin in the 'Nth room' episode of 'I Want to Know That' as being from an "intelligent individual in their mid-40s" being re-highlighted, there is a prevailing atmosphere that the results of Kim Soo-hyun's KakaoTalk message analysis cannot be fully trusted.
Meanwhile, Kim Soo-hyun has filed a defamation suit against the bereaved family and an unidentified person claiming to be his aunt, as well as against the operators of the 'Garosero Research Institute,' for 12 billion won in damages. Kim Soo-hyun stated, "What I have done is what I have done, and I can accept any criticism for that. However, what I have not done is what I have not done. I want to clarify that for all those who still believe in me. I will not ask for anyone to believe in me. I will make sure to prove it," indicating his resolve to fight to the end.
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