The tribunal requested Osorio’s testimony, which took place over two days on March 6 and 7, 2015, and included presentation of an Excel data base of 900 documents drawn mostly from U.S. government sources and from the Archive of Terror in Paraguay. Of these, Osorio focused on 100 declassified records selected for the tribunal, which was presided over by Judge Oscar Amirante, president of Federal Tribunal N° 1.
The National Security Archive obtained the U.S. documents through the Freedom of Information Act (FOIA), primarily from the Central Intelligence Agency, Defense Intelligence Agency and the State Department. Other notable records originated from the Chilean former secret police, DINA.
"We have been working on Operation Condor for years," Osorio said, "sifting through archives in many continents and building a body of knowledge and a trove of documents."
The Pagina 12 feature entitled "The Evolution of Condor," described Osorio’s presentation of "dozens" of documents to the tribunal, and the contribution the documents made in educating the judges on the genesis and evolution of coordinated repression in the Southern Cone. Osorio’s testimony covered a range of topics including the breadth of Condor operations, U.S. knowledge of those operations and the authenticity of the records being introduced into evidence.