Dom Joly: Chilling eyes in the land of the killing fields

I looked into the eyes of evil twice last week. Wandering aimlessly around Cambodia I pretty much fell into a narrative for my book. I was having a drink at the Foreign Correspondents' Club in Siem Reap when a man sidled up to me and inquired as to whether I was a journalist? I said yes. He then asked me whether I wanted to meet a man who was selling Pol Pot's shoes.

If this was a tourist scam, it was a pretty original one. I got into a beaten-up old car and we drove for about 15 minutes until we got to a house on the outskirts of town.

The man met us at the door. He was nutbrown with a squeaky voice and very hospitable. Once seated, he produced two Rolleiflex cameras and a pair of old sandals made from car tyres, as was the custom with the Khmer Rouge. After a brief chat it soon became clear that the sandals were not the story.

The man turned out to be Nhem En, the photographer of the prisoners brought into the notorious Tuol Sleng prison in Phnom Penh to be tortured and then murdered. This man's photographs are now possibly the most poignant and hideous symbols of the genocide committed by Pol Pot's regime in the late Seventies. Here I was, sitting in his living room with his grandchildren running around his feet, smoking Alain Delon cigarettes. I felt sick. Once I realised who this man was I tried to leave as soon as possible, but was unable to do so without going through a protracted souvenir photograph session looking down the lens of evil.

Four days later I was in Tuol Sleng itself, staring at the heartbreaking photographs that Nhem En had taken. With me was Chun Mei, one of only seven survivors from the place. He showed me how he had been shackled to the floor and cudgelled if he moved without permission. His fingers were distorted, the result of endless beatings and of having his fingernails ripped out.

This being Cambodia, however, things weren't quite so black and white. Chun Mei was a member of the Khmer Rouge before the organisation started to turn its murderous intent on itself. Nothing is quite so simple as goodie and baddie, victim and perpetrator, in this unbelievably beautiful country.

One certainty is the guilt of "Comrade Duch", the former commander of Tuol Sleng. He is currently on trial just outside Phnom Penh in a hugely expensive joint UN-Cambodian tribunal.

I found a man who claimed he could get me into the trial. This time we met at the Foreign Correspondents' Club overlooking the river in Phnom Penh. I started to wonder whether all foreign correspondents had it this easy, sitting around drinking gin in their club until a story turned up and tapped them on the shoulder?

When I arrived at the court, disaster: there was a dress code and shorts were a strict no-no. A policeman roared off on a bike and returned with some trousers he offered to "rent" me. Suitably attired, I entered. We sat in a half-empty auditorium looking at the court through a thick wall of glass framed by heavy dark wood.

Two rows of sombre-looking judges faced the defendant. He sat with his back to us, dwarfed by proceedings. Duch's voice however, was strong as he talked about "smashing people to bits" – his term for executions. He was very precise on the tiny details of daily life in Tuol Sleng.

During a short break I walked right up to the glass, as though in a zoo. Duch rose from his seat and turned to look at us, his audience. For three seconds our eyes met – three seconds I shall never forget.