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Incidents

The failed Gunpowder Plot of 1605 was a conspiracy among a group of Roman Catholic gentry to re-establish Catholicism in England by assassinating the Protestant King James I and replacing him with a Catholic monarch. To this end, they placed large quantities of gunpowder beneath the House of Lords, which one of the conspirators, Guy Fawkes, would detonate during the State Opening of Parliament on 5 November 1605. If successful, the explosion would have destroyed the palace, killing the King, his family and most of the aristocracy. However, the plot was discovered and most of the conspirators were either arrested or killed while trying to evade capture. The survivors were tortured in the Tower of London, tried for high treason in Westminster Hall, convicted and gruesomely executed by hanging, drawing and quartering. Since then, the cellars of the palace have been searched by the Yeomen of the Guard before every State Opening of Parliament, a traditional precaution against any similar attempts against the Sovereign.

The execution of Sir Walter Raleigh occurred at the palace of Westminster on 29 October 1618.

The previous Palace of Westminster was also the site of a prime-ministerial assassination on 11 May 1812. While in the lobby of the House of Commons, on his way to a parliamentary inquiry, Spencer Perceval was shot and killed by a Liverpool merchant adventurer, John Bellingham. Perceval remains the only British Prime Minister to have been assassinated.

The New Palace became the target of Fenian bombs on 24 January 1885, along with the Tower of London. The first bomb, a black bag containing dynamite, was discovered by a visitor on the steps towards the Chapel of St Mary Undercroft. Police Constable (PC) William Cole attempted to carry it to New Palace Yard, but the bag became so hot that Cole dropped it and it exploded. The blast opened a crater in the floor 1 metre (3 ft) in diameter, damaged the roof of the chapel and shattered all the windows in the Hall, including the stained-glass South Window at St Stephen's Porch. Both Cole and PC Cox, a colleague who had joined him to offer assistance, were seriously injured. A second explosion followed almost immediately in the Commons Chamber, causing great damage—especially to its south end—but no injuries, as it was empty at the time. The incident resulted in the closure of Westminster Hall to visitors for several years; when visitors were re-admitted in 1889, it was under certain restrictions and never while the two Houses were sitting.

On 17 June 1974, a 9-kilogram (20 lb) bomb planted by the Provisional IRA exploded in Westminster Hall. The explosion and the resulting fire, which was fed by a ruptured gas main, injured 11 people and caused extensive damage. Five years later, a car bomb claimed the life of Airey Neave, a prominent Conservative politician, while he was driving out of the Commons car park in New Palace Yard. The attack occurred on 30 March 1979, one day after the announcement of that year's general election; both the Irish National Liberation Army and the Provisional IRA claimed responsibility for Neave's assassination, but it is now accepted that the former were responsible.

The palace has also been the scene of numerous acts of politically motivated " direct action ", which often took place in the Chamber of the House of Commons. In July 1970, a man in the Strangers' Gallery threw two canisters of tear gas into the Chamber to protest against the use of such gas in Northern Ireland; an MP and two members of the House's staff were taken to hospital and the sitting was suspended for almost two hours. In 1978, activist Yana Mintoff and another dissident threw bags of horse manure, and in June 1996 demonstrators dropped leaflets. Concern about such attacks and a possible chemical or biological attack led to the installation of a glass screen across the Strangers' Gallery in early 2004.

The new barrier does not cover the gallery in front of the Strangers' Gallery, which is reserved for ambassadors, members of the House of Lords, guests of MPs and other dignitaries, and in May 2004 protesters from Fathers 4 Justice attacked Prime Minister Tony Blair with flour bombs from this part, after obtaining admission by bidding for a place in the visitors' gallery in a charity auction. Subsequently, rules on admission to the visitors' galleries were changed, and now individuals wishing to sit in the galleries must first obtain a written pass from a Member certifying that that individual is personally known to them. In September of the same year, five protesters opposed to the proposed ban on fox hunting disrupted the proceedings of the House of Commons by running into the Chamber, the first such occurrence since King Charles I 's unauthorised entry in 1642, which triggered the English Civil War.

The House of Lords has also been targeted by protesters. On 2 February 1988, the House debated the Local Government Bill 's controversial Clause 28, a measure to prohibit the promotion of homosexuality in schools. Following the division, in which the clause passed, a number of lesbian demonstrators in the public gallery started chanting slogans, and three of them tied ropes to the railing and climbed down onto the floor of the Chamber. Lord Monkswell, who had provided the women with passes to attend the debate, later apologised to the House for the incident but did not criticise the protest.

Similar actions have been carried out outside the Palace of Westminster. Early in the morning of 20 March 2004, two Greenpeace members scaled the Clock Tower to demonstrate against the Iraq War, raising questions about the security around such a likely target of terrorist attacks. In March 2007, another four members of Greenpeace made their way to the palace's roof by means of a nearby crane, which was being used for repairs to Westminster Bridge. Once up, they unfurled a 15-metre (50 ft) banner protesting against the British government's plans to update the Trident nuclear programme.

In February 2008, five campaigners from the Plane Stupid group gained admittance to the building as visitors and then moved up to the roof to demonstrate against the proposed expansion of Heathrow Airport; from there they hung two banners they had smuggled past security. MPs and security experts found it worrying that the protesters made it to the roof in spite of the heightened security measures, and the prosecution at the activists' trial argued that they may have received help from a House of Lords employee. In October 2009, at least forty Greenpeace activists climbed to the roof of Westminster Hall to call for the adoption of policies combating climate change. Some of them climbed down after nearly five hours, while the rest spent the night on the roof.

On 22 March 2017 an Islamist -related terror attack was carried out in which a man stabbed a police officer after ploughing into pedestrians on Westminster Bridge. Five people were killed, including the attacker and the police officer. In August 2018 there was another attack, treated by prosecutors as terrorism.

On 1 April 2019, a group of environmental protestors from the group Extinction Rebellion stripped semi-naked in the public gallery during a Brexit debate and glued themselves to the handrail and glass screen with their buttocks facing the Commons Chamber. MPs attempted to continue the debate, some of them incorporating puns and references to nakedness into their speeches, to much hilarity.

There have been four fires on the Palace of Westminster site during 2019, and eight in 2018.

In 2022, the body of the late Queen Elizabeth was left inside the hall for people to pay their respects. A man decided to jump the barriers and pull away the flag draped over the coffin. He was detained and taken away by police and officials.