Potentially damning archives from Khmer Rouge-era provincial prisons were “systematically destroyed” in the district controlled by former Senate president Chea Sim for political expediency, expert witness Henri Locard told the Khmer Rouge tribunal yesterday.

Locard told the tribunal it had failed to adequately investigate the brutal crimes committed inside provincial prisons in general, even as it delved deeply into the regime’s notorious S-21.

While written confessions and photographs from S-21 – as well as the physical premises (today the Tuol Sleng Genocide Museum) – are extant, records of the smaller prisons that Locard said dotted every district are rare.

“There are Tuol Slengs all over the country,” he said, adding the court’s intense scrutiny of the capital’s prison – many of its inmates Khmer Rouge cadre – was like an investigation of the Nazi regime examining only Auschwitz.

He said some of the evidence from these centres was destroyed – “in particular in Chea Sim’s district”. Sim, who was president of the ruling Cambodia People’s Party (CPP) until his death last year, oversaw the East Zone’s Ponhea Krek district during the regime, before fleeing to Vietnam amid purges.

“People saw his name was in those papers and [they] were systematically destroyed,” Locard said. “I think there was certain type of revisionism . . . there was also a will, a desire to make the archives disappear, and I regret that very much.”

Locard said he was prompted to travel the far reaches of the country, where at times elephant was the only mode of transport, in the early 1990s in search of witnesses and evidence of these prisons; he felt a personal affinity with Cambodia as he studied in the Kingdom in the mid-1960s.

“I wanted to understand . . . why some of the dear friends I had known . . . had disappeared,” he said. “All classes were taken to these dens of horror, even the most innocent victims.”

“Democratic Kampuchea was like a prison without walls. People had no freedom whatsoever.”

Another oversight of the tribunal, he said, was the fate of the “Kloengs”, people from India and Pakistan. Locard said he had evidence these groups were “exterminated” at the beginning of the regime, “simply because of their ethnic origin”.

Locard, an author of many works on the regime, said his Pol Pot’s Little Red Book was a project begun in jest. “I collected them just for fun,” he said. “People made fun of the Khmer Rouge by whispering counter-slogans.”