Journalist and author Philip Short found his work – and even his personal perspective – the subject of severe scrutiny as his testimony continued at the Khmer Rouge tribunal yesterday.

With the prosecution ceding the floor before the mid-day break, the defence for co-accused Nuon Chea sought to impugn the credibility of the Pol Pot biographer’s sources, and seemingly called into question the expertise of the expert witness on the subject of Cambodian communism.

When pressed on the sources of his assertion that there was a Khmer Rouge policy of executing soldiers and officials of the toppled Lon Nol regime, Short fired back that “biography, like politics, is the art of the possible”.

“You check, you verify that your information is consistent with other information, but a biographer is not a judge in a court of law. The burden of proof, thankfully, is lower,” he said, adding that he consulted multiple sources. “These facts were consistent with all the facts I had gathered on the subject, so yes, I think it was fair to make a judgement.”

After continuing to be pressed on the subject of such executions after the fall of Oudong, Short reiterated his sources and his position that such a policy existed, adding that defence counsel Victor Koppe did “not have to accept my belief, but it is my belief that this happened”.

“Is it true that what you have been saying about Oudong, to quote your earlier testimony, is reliable for a book, but not reliable for this court?” Koppe replied, before quickly withdrawing the question.

Koppe went on to question how Short was able to double-check allegations made by his interviewees, especially when information came from a single source.

“I was quite lucky to find just one source with that kind of information,” Short said of an account of a moment shared by Nuon Chea and a mid-level cadre.

“With respect, that is a very lawyerly question,” he went on, when pressed again. “When you asked if it was reliable for a court of law . . . yes, it is reliable for a court of law, but it wasn’t written with a court of law in mind. The standard of proof you are seeking was not the standard of proof I was using to determine the truth as a historian.”

When asked about his qualifications as an academic expert on communism, Short replied that “I’m not, nor would I pretend to be, nor would I wish to be” one, maintaining that, nonetheless, he was capable of drawing comparisons.

“Steve Heder, and others like him – David Chandler and Ben Kiernan – devoted their whole lives to studying Cambodia . . . My qualifications are different,” he said. “I have looked at, and lived under, communist systems in Russia and China. They have not . . . That provides a very different perspective than that of an academic [who] works only in that subject.”