U.S. DOJ Office of Special Investigations

The Office of Special Investigations was a unit within the Criminal Division of the United States Department of Justice. Its purpose was to detect and investigate individuals who took part in state sponsored acts committed in violation of public international law, such as crimes against humanity.

In 2010, the Office was merged with the Domestic Security Section to form a new unit of the Criminal Division: the Human Rights and Special Prosecutions Section. A redacted report about the office's work was released to the National Security Archives after a FOIA request. A complete report was leaked to the New York Times, and according to David Sobel, the redactions were "without legal justification."

In 1964 it was discovered that Hermine Braunsteiner, married Ryan, a former SS guard in the concentration camps Ravensbrück and Majdanek, lived in the United States. The case caused quite a stir and, in consequence, a special working group was set up at the immigration authority, which should identify other war criminals from the Nazi-era, who lived in the United States. This working group was under great public pressure, and was not sufficiently prepared for the task handling a large number of complex investigations. During 1977–1979, the department initiated five cases, all except one were lost. In the one case won it turned out later that an alleged Gestapo officer was in fact a former forced laborer.

As a consequence, the New York Congresswoman Elizabeth Holtzman called for the creation of a special unit to prosecute war criminals residing in the United States. In 1979 the Office of Special Investigations was established within the US Department of Justice. Its task consisted of processing the accumulated cases and the resumption of the search for war criminals in the United States. The OSI was equipped with greater powers than any other department. Its employees were able to do all necessary steps themselves, from a first investigation to litigation, negotiating with foreign governments and calling for support of other U.S. authorities.

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