The PSIA is an administrative body established on July 21, 1952, when the Subversive Activities Prevention Act came into force to conduct investigations and request for dispositions aimed controlling subversive organizations in an integrated manner as stipulated in the act. In addition, the Act on the Control of Organizations Which Have Committed Acts of Indiscriminate Mass Murder came into force on December 27, 1999. This act gave the PSIA additional duties to conduct investigations, request for dispositions, and take control measures with respect to organizations that have committed indiscriminate mass murder.