When prosecutors needed to prove that the regime’s policies amounted to genocide against the Cham Muslim minority and the Vietnamese, they turned to Chheng’s spreadsheets. He created a relational database that matched prison logs with mass grave coordinates. He proved, beyond a reasonable doubt, that the killing was not chaotic but systematic.
"I have seen the signature of the man who killed my cousin," he told a Phnom Penh Post reporter in 2012. "I have read the confession of the woman who lived next door to me in Battambang. She confessed to being a Vietnamese spy. She was a rice farmer. She was 22. She had a baby." ly chheng biography
That changed in 1995 when Yale University opened the . For the first time, there was a systematic effort to locate, preserve, and digitize the paper trail the Khmer Rouge had left behind. The regime was famously bureaucratic: they kept records of arrests, confessions (often tortured), and executions. When prosecutors needed to prove that the regime’s
"Justice is not just about prison cells," he says. "Justice is about a daughter knowing what happened to her father. Justice is about a village building a stupa of bones so the spirits can rest." "I have seen the signature of the man
For nearly four decades, has sat at the intersection of memory and mathematics. As the chief document examiner and senior investigator for the Documentation Center of Cambodia (DC-Cam) , his life’s work has been to count the uncountable: the 1.7 million to 2.2 million Cambodians who perished during the Khmer Rouge regime (1975–1979).
"The handwriting was beautiful," Chheng recalls in a rare 2018 interview. "The prisoners were teachers, doctors, poets. They wrote their own death warrants because they were told if they confessed, they would live. They never lived." Chheng’s unique skill is his ability to read between the lines of Khmer Rouge documentation. He doesn’t just translate the words; he decodes the subtext. A "confession" of spying for the CIA was almost always a fabrication. A note that a prisoner was "sent for re-education" was a euphemism for execution.
In 1997, Chheng joined DC-Cam, the program’s in-country arm. His job was staggering: to process the contents of , the secret prison where over 12,000 people were tortured and killed. He spent years reading the confessions of the doomed—documents written in desperation, signed with thumbprints stained by blood.