Switzerland Publishes Secret Intelligence File on Nazi Doctor Josef Mengele

Switzerland’s Federal Intelligence Service has published a previously restricted intelligence file on Nazi war criminal Josef Mengele, making the roughly 200-page dossier available to the public decades earlier than originally planned.

Mengele served as a doctor at the Auschwitz extermination camp, where he became notorious for brutal medical experiments on prisoners, including children and twins.

Around 1.1 million people were murdered at Auschwitz during World War II, approximately one million of them Jews.

The newly released file could help historians determine whether Mengele entered Switzerland while authorities were searching for him after the war.

Documents in the dossier suggest he may have traveled through Switzerland or considered entering the country under a false identity while evading capture. Historians have long sought access to the records to establish whether Swiss authorities may have failed to identify him during his years as a fugitive.

After the war, Mengele escaped Germany using a false identity and eventually fled to South America. He lived for decades in Argentina, Paraguay and Brazil without facing trial.

He died in Brazil in 1979 after suffering a stroke while swimming. His identity was only conclusively confirmed years later.

The Swiss file was compiled by the police service of the Office of the Attorney General, a predecessor of the country’s current Federal Intelligence Service. Authorities transferred the dossier to the Swiss Federal Archives in 2001.

Under Swiss archival rules, the records were subject to an extended protection period lasting until the end of 2071.

Authorities repeatedly rejected requests to view them, including one submitted by historian Gérard Wettstein in February 2026. Wettstein appealed the decision to Switzerland’s Federal Administrative Court.

During the appeal, officials discovered that the file had previously been examined by the Bergier Commission, which investigated Switzerland’s relationship with Nazi Germany during World War II.

Documents reviewed by that commission are subject to a 2001 government decision calling for a more liberal approach to public access. The intelligence service subsequently reconsidered its earlier refusal and approved the release on September 8.

Swiss authorities said they chose to publish the dossier online because of the exceptionally high level of public interest and the large number of requests to examine it.

Some passages remain redacted to protect intelligence sources and private individuals. However, the Federal Intelligence Service said it limited the redactions so that the documents and the events they describe remain understandable.

The agency said the case has also prompted a broader review of how Switzerland handles public access to historical intelligence records.