What Does It Take To Be A Mass-Murderer?

A case study from the Cambodian genocide

Tom Stevenson
6 min readMar 12, 2019


Photo by Steve DeBeus on Reshot

On 26 July 2010, Kaing Guek Eav, better known as Comrade Duch, the head of the notorious Tuol Sleng (S-21) prison in Cambodia was formally charged with crimes against humanity and sentenced to 35 years in jail, for his part in the genocide that occurred in Cambodia between 1975 and 1979.

Almost forty years after the fall of the Khmer Rouge regime which was responsible for the atrocities; he became the first of the perpetrators to be prosecuted for his involvement.

Following his trial, five years were taken off his sentence. This would see him set free if he reaches the age of 87 in 2029.

Duch is a lesser-known figure to the wider world, but he is an interesting case study about the people that are complicit in genocide. He trained to be a mathematics teacher, before joining the Communist Party of Kampuchea.

We often like to think of the figures involved in genocide as beyond the pale. Grotesque monsters who are the very personification of evil. The reality is much more stark and humbling.

They are often everyday folk like you and me who have become entangled in ideologies and beliefs in the superiority of their views over others. Genocide is mass killing on an industrial scale, for this to be accomplished there needs to be a large number of willing participants.

The crimes that Duch committed during the Cambodian genocide show it doesn't take much for humans to descend into monsters

Duch’s story is a remarkable one, the maths teacher turned brutal prison commandant responsible for the deaths of an estimated 12,000 people.

His evasion of Cambodian and international authorities for twenty years, before being brought to justice for his part in one of the most harrowing episodes of the twentieth century is a tale of justice finally being served.

Comrade Duch

Ironically, the former maths teacher was in charge of the most notorious prison, S-21, before the rise of the Khmer Rouge when it had been a school.



Tom Stevenson