Stormontgate

Stormontgate is the name given to the controversy surrounding an alleged Provisional Irish Republican Army spy ring and intelligence-gathering operation based in Stormont, the parliament building of Northern Ireland. The term was coined in October 2002 after the arrest of Sinn Féin’s Northern Ireland Assembly group administrator Denis Donaldson, his son-in-law Ciarán Kearney, and former porter William Mackessy for intelligence-gathering on 4 October 2002.

Ten days after the arrests, devolved government in Northern Ireland arising from the Good Friday Agreement collapsed. The raid involved "scores" of Police Service of Northern Ireland officers who entered the building to remove two computer disks from the Sinn Féin offices. Thousands of documents were reportedly discovered by the police in Donaldson's Belfast home.

On 8 December 2005 the charges against all three men were dropped by the Northern Ireland Public Prosecution Service. Lawyers for the service said that "the prosecution for the offences in relation to the accused are no longer in the public interest". Sinn Féin claimed that the prosecutions had been politically motivated and were dropped because of lack of evidence. Some unionists suggested that dropping the charges was a "reward" for the final act of decommissioning by the Provisional IRA announced on 26 September 2005.

On 16 December 2005, Sinn Féin president Gerry Adams announced to a press conference in Dublin that Donaldson had been a spy in the pay of MI5 for over twenty years. This was confirmed by Donaldson in a statement to broadcast media outlet RTÉ shortly afterwards.

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