Joseph Stalin

The release of the Katyn decision papers in 1992 put Stalin's approval of the execution of Polish prisoners directly into the documentary record. Soviet authorities had blamed Nazi Germany for decades before acknowledging NKVD responsibility in 1990. The signed leadership documents strengthened the case for responsibility at the top, rather than an unauthorised local crime. This was confirmation of what many investigators already believed, not the discovery that Stalin's regime used mass violence; access to the wider record also remained incomplete.