Official Secrets Act (U.K.)
The Official Secrets Act (OSA) is a significant piece of legislation in the United Kingdom, originally enacted in 1911 to combat espionage and safeguard national security. This act established legal frameworks for prosecuting individuals, particularly current and former government employees, who disclose sensitive official information without authorization. Over the years, the OSA has undergone several amendments, notably in 1920 and 1939, but its most contentious clause is section 2, which criminalizes unauthorized sharing of information deemed "official."
The act has faced criticism from civil libertarians and historians, particularly in the late 20th century, for its vague terminology, which allows for varying interpretations of what constitutes "official information" and "national security." Critics argue that the law is often misused to suppress information that could reveal governmental misconduct or incompetence, particularly concerning intelligence agencies like MI5 and MI6. A notable instance of this scrutiny occurred in the 1980s, during a high-profile legal battle involving Peter Wright, a former MI5 officer, and his memoirs, "Spycatcher," which the government attempted to block. Despite calls for reform, significant changes to the OSA have not materialized, reflecting ongoing tensions between national security interests and the public's right to know.
Subject Terms
Official Secrets Act (U.K.)
Enacted: August 22, 1911
Place: United Kingdom (national)
Significance: This act has frequently been used by British governments to suppress publication of materials alleged to threaten the nation’s security and vital interests
The Official Secrets Act (OSA) was originally passed by the British Parliament to deter spying and to establish legal procedures and penalties for those who betrayed Britain’s national interests. The 1911 act—which was actually a substantial revision of a similar law passed in 1889—has been periodically amended, most notably in 1920 and 1939. Its most controversial provision, section 2, effectively prohibits the unauthorized disclosure of official information acquired by current or former governmental employees in the course of their work. The act also provides punishments for anyone who receives such information knowing that it has been passed on in violation of the law.

After the 1970’s the OSA came under increasing attack. Civil libertarians were concerned about vague phrases in the act, such as “official information” and “national security,” which could be variously interpreted. Historians believed that the government occasionally looked foolish in attempting to suppress books about events that had occurred far in the past and whose principal participants were dead. Above all, however, there was a growing suspicion that the OSA was being misused to suppress information exposing the incompetence, treachery, fiscal mismanagement, and blatant illegalities of government agents and agencies. This was particularly true of written materials that dealt with Britain’s major security organizations, MI5 (counterintelligence) and MI6 (espionage abroad).
Perhaps the most celebrated case involving the OSA began in 1985, when the government of Prime Minister Margaret Thatcher attempted unsuccessfully to prevent Peter Wright, a former member of MI5, from publishing his memoirs, Spycatcher. Despite repeated protestations to liberalize the act by successive governments, no substantive reforms had been accomplished by the mid-1990’s.