khoji parkCrime · Hwaseong · 1986–2020
The Serial Killer Was Already in Prison
The search was vast, but its answer remained out of reach.
Read in slides1. A region living with fear
Beginning in 1986, a series of killings around Hwaseong shocked South Korea and generated an enormous investigation. Police questioned many people and pursued suspects over years without identifying the offender responsible for the series. The crimes became a lasting national trauma, while the scale of the investigation did not guarantee that its methods would produce the truth.
The search was vast, but its answer remained out of reach.
2. One conviction did not solve the pattern
A man known publicly as Yoon was convicted in one of the cases and spent years in prison. His conviction did not end the wider investigation, and he maintained that his confession had been coerced. The later history would show why a confession and a closed case file must still be tested against independent evidence.
An official answer existed for one victim—and it was the wrong one.
3. Evidence waits for technology
Physical evidence from the crimes remained available as forensic methods advanced. In 2019, DNA testing linked material from the old cases to Lee Choon-jae. The match was a major breakthrough because it connected the historical investigation to a specific person, rather than another suspect selected chiefly through interrogation, resemblance or proximity to the crime scenes.
A preserved trace finally did what thousands of questions had not.
4. The suspect is in custody already
Lee was already serving a life sentence for murdering his sister-in-law in a separate 1994 case. Identifying him therefore did not require a dramatic chase across the country. The discovery instead exposed a painful irony: investigators had sought the serial killer for decades while the man eventually linked to the crimes was already inside the prison system.
The fugitive in the public imagination was not a fugitive at all.
5. Confessions and expired deadlines
Lee confessed to further killings, and police linked him to the Hwaseong series. The statute of limitations prevented prosecution for those old murders, despite the new evidence. That legal barrier did not undo his separate life sentence, but it created a distinction between an investigative identification and the possibility of bringing new charges for each historical offence.
The evidence had caught up after the legal clock had run out.
6. A wrongful conviction undone
Yoon received a retrial, and in December 2020 the court acquitted him. The result acknowledged a grave miscarriage of justice after he had already lost many years to imprisonment. The breakthrough therefore changed two histories at once: the identification of the serial offender and the clearing of a man convicted of a crime he did not commit.
Solving the case also meant admitting that an earlier solution was false.
7. The second cost of a failed investigation
The Hwaseong story is about victims, a delayed identification and the consequences of unreliable investigative methods. It inspired fictional films, but their scenes are not evidence for this account. The documented reversal is powerful enough: preserved DNA named an imprisoned killer, while a separate courtroom finally removed a wrongful conviction that had stood for decades.
The new evidence found a killer—and exposed another victim of the investigation.