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In 1967, a political scandal known as the D-notice affair occurred, when Prime Minister Harold Wilson made an attack on the Daily Express newspaper, accusing it of breaching two D-notices which advised the press not to publish material which might damage national security. When the newspaper asserted it had not been advised of any breach, an inquiry was set up under a committee of Privy Counsellors. The committee found against the government, whereupon the government refused to accept its findings on the disputed article, prompting press outrage and the resignation of the Secretary of the D-notice committee.
It has been reported[by whom?] that in 1971, four days following the Baker Street robbery, a D-Notice was issued, requesting that reporting be discontinued for reasons of national security. It is claimed that some security boxes contained embarrassing or nationally sensitive material. However, an investigation some years later showed that a request had never been made to the D-Notice committee.[4] In fact, The Times newspaper was still reporting about the case over two months later.[5]
In 2004 and 2005, three blanket letters were sent to newspapers advising against publication of countermeasures used against roadside ambushes of British forces in the Iraq War.[3]
On 8 April 2009, the Committee issued a DA-Notice in relation to sensitive anti-terror documents photographed when Assistant Commissioner Bob Quick arrived at Downing Street for talks about current police intelligence.[6]
On 25 November 2010, the Committee issued a note to editors drawing attention to standing DA-Notices 1 and 5 in relation to sensitive documents expected to be released on the website WikiLeaks.[7][8][9][10]
In June 2013, a DA-Notice was issued asking the media to refrain from running stories on the US PRISM surveillance programme, and on British involvement therein.[11]
In October 2013, Prime Minister David Cameron made a veiled threat to newspapers over NSA and GCHQ leaks, stating in Parliament that the government might use "injunctions or D-notices or the other tougher measures" to restrain publication of leaked classified information if newspapers did not voluntarily stop publishing them.[12]
In 2017, a notice was issued to British journalists regarding revealing the author of a controversial dossier alleging collusion between Donald Trump and the Russian government during the 2016 presidential election.[13] Multiple British outlets ignored this advisory and revealed his name anyway, including BBC News, The Daily Telegraph and The Guardian.[13]
On 7 March 2018 and on 14 March 2018 two notices were issued to protect MI6 in relation to some aspects of the Skripal affair. In the early 1990s Sergei Skripal was recruited by Pablo Miller, the MI6 agent inside the UK embassy to Estonia in Tallinn. The MI6 officer under diplomatic cover in Moscow at this time was Christopher Steele. Miller was also the handler of Skripal after he went to jail and was released by Russia in a spy swap. Both lived in Salisbury. Steele and Miller worked for Orbis Business Intelligence which compiled the controversial Trump–Russia dossier, comprising 17 memos written in 2016 alleging misconduct and conspiracy between Donald Trump's presidential campaign and the Putin administration. While the precise nature of the relations between Skripal, Miller, and Steele were hidden, enough was already known to raise questions about Skripal's ongoing involvement with British intelligence.[14][15][16]