Chilean investigative journalist Carola Fuentes first broke the story about Colonia Dignidad, a German sect in southern Chile led by a former Nazi army nurse, Paul Schaefer. Residents of the Colony were often drugged and the children sexually abused. But the residents were not Schaefer's only victims. Colonia Dignidad was also an experimental torture centre where political prisoners of the Pinochet regime were interrogated, tortured and their bodies sometimes disposed of.
In 1996, a lawyer named Hernan Fernandez dared to take on Schaefer, but the German sect leader fled to Argentina. That was where Fuentes went in search of him. He was eventually captured and imprisoned for the sexual abuse of minors.
The first trip to Argentina was to follow up on some clues, some streets where we could open some doors or close them, to rule out that Schaefer was there. One piece of information led to a small town south of Buenos Aires which was called Chivilcoy.
This town had very similar features to Parral, home of Colonia Dignidad, and it was a sign that the investigation was going well; they had a similar climate, an aerodrome, a place with a lot of land, lots of immigrants.
We found a van which was registered to Peter Schmidt. We knew he was one of the [people] close to Schaefer in Colonia. He had disappeared alongside Schaefer in 1996. The van was registered to an address in the centre of Chivilcoy. When we got to this address it turned out to be a motorbike rental shop, owned by an Italian man. When I started to speak to him, I disguised myself as a German tourist so he wouldn't be suspicious of me.
He said to me: "Oh, you're German, I have some German friends, Peter and Felipe."
And I swear, my heart was beating [quickly].
Then he said: "Yes they have a cheese factory, they make a lot of cheese."
From there I was nervous thinking it could be them, but he didn't give me any more clues.
We started to search the land to see if anyone knew of a German cheese factory, nobody knew anything, so we decided to stand guard outside the bike shop. One night, [Peter Schmidt arrived] in the same van we had details for. We filmed him with our camera, from a distance. We then compared the images with photos we had and decided that yes, he was Schaefer's bodyguard.
That night we followed him, in darkness, through the country roads. [It was completely] dark except for the two red tail-lights which suddenly turned into a small path. We stopped, noted the details and the next day we came back and discovered 'La Solita'. It was this ranch, which a year later we discovered was where Schaefer was holed-up. But from that day until Schaefer was arrested, we never saw Paul Schaefer. I did not know if he was dead or alive.
I didn't know if we were following a right or wrong clue and the worse thing was I didn't know if any step we took would alert him and cause him to escape.
One of our journalists infiltrated the place and met the neighbours but no one spoke of an older man. Until one of the colonials, Fritz Scheiner, who is called Felipe in Argentina, gave the understanding that an older man lived with them, an older man who had some war wounds, who was ill. These clues made us believe he was probably there.
We compared the details of who was living there and what they were doing. We shared our information with a lawyer - Hernan Fernandez - and concluded there was no reason for this group to be there if not to protect Schaefer. We went to the Argentine police to ask them to start a formal enquiry.
A symbol of impunity
We didn't go to the Chilean authorities and never planned to. In fact, all aspects of the investigation were done in a guarded fashion. It was very secretive, we feared the Chilean police or authorities would know we were carrying out this investigation. They had allowed Schaefer to be hidden for 10 years and for 40 years they had allowed Schaefer to commit all the crimes he committed in Chile.
He had a huge network of protection and I was very scared that if the Chilean police or someone in Chile found out we were looking for him they'd warn him and he'd escape again.
Paul Schaefer had become a symbol of impunity.
He committed unspeakable crimes - before the dictatorship, during the dictatorship and he continued to commit them once Chile had a democracy. Sexual abuses against Chilean children were committed when Chile had become a democracy. All of this with impunity thanks to the protection network he managed to build.
How did he build that protection network? It's something that still needs to be investigated. Many say it was by favours, others say blackmail, with the information he had on important people who were told if they didn't help him he could let their information out.
But this protection network had allowed Schaefer to commit these crimes with impunity and escape with impunity.
A lot of us asked ourselves how was it that the colonials had, during all those years, done what Schaefer wanted them to do? How did they work for free Monday to Sunday without rest? How did they not receive money in exchange for their work? How did they allow the separation of fathers, mothers and children?
Many gave an understanding that it was because the colonials were disabled or that they had blind faith in Paul Schaefer, which was some kind of a cult. I discovered that in Colonia Dignidad there was a method of drugs, to drug the colonials to dope them and force them to work in this kind of slavery. The colonials didn't accept slavery voluntarily, they were given drugs every day, they told them it was for epilepsy, for schizophrenia or for different illnesses.
And those drugs, what they did was inhibit their free will. That way the colonials worked from sunrise to sunset without complaint; they accepted the tortures and accepted the beatings.
Many colonials told me that every morning the routine was to go to the pharmacy where they would be given their medicine. I went and I found those medicines and I asked for them to be analysed. They told me that they were medicines for epilepsy, for example. I went to the specialists and ... those specialists carried out tests on [some of the colonials] - they didn't have epilepsy. Therefore, the conclusion was that the medicines were to dope them and subdue their free will.
Then I investigated how the Colony had managed to get this amount of psycho-pharmaceutical drugs and I discovered the hospital in Talca at that time had given them all those drugs without even asking for a prescription in return, which would prove that they were for people with epilepsy. They gave them out freely.
'We let this happen'
I think it's very pernicious to be able to know the truth and for what happened in Colonia Dignidad to still be classified information.
I imagine that in those files there is sensitive information which could affect people who today have authority or are politicians ... or public figures. But in keeping that information secret, it inhibits us from knowing what really happened in Colonia Dignidad and how Schaefer managed to build his network of protection.
The longer the judge keeps these files a secret, the more our imagination grows. And even worse, the increased risk that this country throws earth over a case which was not isolated or accidental. Us, the Chileans, including the journalists, let this happen. And if we don't know the truth, it could happen again."
Al Jazeera Correspondent can be seen each week at the following times GMT: Thursday: 2000; Friday: 1200; Saturday: 0100; Sunday: 0600; Monday: 2000; Tuesday: 1130; Wednesday: 0100; Thursday: 0600.
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