[6] The IRA claimed responsibility for the attacks by deliberately mirroring Prime Minister Margaret Thatcher's words a few months before when Britain entered the Falklands War, proclaiming that "the Irish people have sovereign and national rights which no task or occupational force can put down".

[3] Reacting to the bombing, Thatcher stated: "These callous and cowardly crimes have been committed by evil, brutal men who know nothing of democracy.

[3] The CIA and the FBI ramped up their anti-IRA activity, and public opinion polls showed that sympathy for the IRA in particular, and Irish re-unification in general, plummeted in the United States in response to the attacks.

[2] Sefton's rider at the time of the bombing, Michael Pedersen, survived but he told his doctor that he was suffering from post-traumatic stress disorder; after splitting from his wife, he committed suicide in September 2012 after stabbing to death two of his children.

[11] A memorial marks the spot of the Hyde Park bombing; and the troop honours it daily with an eyes-left and salute with drawn swords.

In October 1987, 27-year-old Gilbert "Danny" McNamee, from County Armagh, was sentenced at the Old Bailey to 25 years in prison for his role in the Hyde Park bombing and others.

In December 1998, shortly after his release from the Maze prison under the Good Friday Agreement, three Court of Appeal judges quashed his conviction, deeming it "unsafe" because of withheld fingerprint evidence that implicated other bomb-makers.

[14] On 19 May 2013, 61-year-old John Anthony Downey, from County Donegal, was charged with murder in relation to the Hyde Park bomb and intending to cause an explosion likely to endanger life.

Although the assurance was made in error and the police realised the mistake, it was never withdrawn, and the judge ruled that therefore the defendant had been misled and prosecuting him would be an abuse of executive power.

[18][19] In December 2019 the High Court ruled, in a civil action against Downey by the family of a victim, that he had been an "active participant" in the Hyde Park bombing, subject to a claim for damages.