Afghan warlord Faryadi Zardad has been convicted by a British court of torture and kidnapping in Afghanistan in a landmark judgement.
Zardad was brought to justice after the BBC's John Simpson - investigating for Newsnight - tracked him down in South London.
In 1999 we were in Kabul, conducting an interview with Mutawakil, the Taleban Foreign Minister. It was a long, tough interview about why the Taleban were prepared to shelter Osama Bin Laden.
During one of his answers Mutawakil hit back. "Well, you British are sheltering the criminal Commander Zardad," he said.
Commander Zardad was a man I knew nothing about. The Foreign Minister told me about the man who ran the checkpoint on the road to Sarobi. The dangers of the road were well known, but I'd never heard of Zardad. I told the foreign minister we would look into it.
Zardad kept a "human dog" to savage his victims
We tracked him down with the help of the Afghan exile community in London. Many of them were extremely angry that a man with the record of Zardad had managed to get into the UK. Particularly when so many of their compatriots had to stay in Afghanistan.
It took almost a year, but eventually we found him living in South London.
We staked the house out for three or four days just to make sure that this was our man. A neighbour let us use his front room to watch people come and go.
We soon recognised the man we knew as Zardad, but the man was living there under a different name. We needed to make one last check to be sure. One of the cameramen posed as a delivery man, with a parcel addressed to Mr Zardad. He banged on the door.
"A parcel for Mr Zardad?"
"Yes, that's me."
We had our man. We moved in with our other camera and introduced ourselves. To our surprise he invited us in. He was very polite, offered us tea, but just as we were about to sit down he ran out of the room.
We sat there nervously for a few minutes. We began to think he'd run off to get a knife or even a gun. When he finally re-emerged, his hands were shaking.
We began to talk. Quickly he denied all the crimes he had been accused of. Yes, he had worked at the road block, but he was a hero of the resistance, he said.
We knew from the people we had spoken to in London and Afghanistan Zardad had had complete power over the hundred - perhaps thousands - of people who drove down the road to Sarobi. He had exercised it with a rare streak of cruelty.
But, of course, he didn't demonstrate that sitting in a small house in South London.
With the evidence we had, there was little doubt he was a criminal. The court proceedings in the UK are the best thing for him.
John Simpson's film for Newsnight was originally broadcast on 26 July 2000.