During the early 1980s she was reportedly one of only five people aware that Oleg Gordievsky, the deputy head of the KGB at the Soviet embassy in London, was actually a double agent.

[24] On 10 September 2005, she spoke to an audience in the Netherlands about the 7 July 2005 London bombings and her disappointment that MI5 failed to stop attacks, even when in possession of intelligence, because of bureaucratic inertia.

She added that "[the] world has changed and there needs to be a debate on whether some erosion of [the] civil liberties we all value may be necessary to improve the chances of our citizens not being blown apart as they go about their daily lives.

"[25][26] On 21 October 2005, BBC News reported Manningham-Buller's leaked court statement to the Law Lords regarding methods for collecting intelligence from overseas.

[27] Her example to support the need for intelligence gathering from overseas was the case of Mohammed Megeurba, an Algerian man who was questioned by agencies in his country.

Shami Chakrabarti, director of human rights organisation Liberty, commended Manningham-Buller for being "brutally honest" about the activities of intelligence agencies.

In September 2011 Eliza Manningham-Buller delivered one of the BBC Radio Reith Lectures and answered questions from an audience that included historian Peter Hennessy and novelist Ian McEwan.

Furthermore, Lady Manningham-Buller maintained that "complete security" could never be achieved in a country and that civil liberties were at risk of being compromised if the plans were passed by the House of Lords.

Martin Kettle, writing in The Guardian on 11 July 2008, described it as "devastatingly succinct" and "the fatal shot" which would ensure that the Government's "plans were holed below the water line".

[35] James Kirkup of The Daily Telegraph described it as "a huge blow to Gordon Brown's plans to extend the detention of terrorist suspects to 42 days".

[37] Giving a lecture in the House of Lords, Baroness Manningham-Buller said "the government did lodge protests" to its US counterparts once the extent of torture was known.

[39] Manningham-Buller was a castaway on Desert Island Discs broadcast on BBC Radio 4 in November 2007 giving her first interview after her retirement.

[5] In June 2011, the BBC announced Eliza Manningham-Buller would present the 2011 Reith Lectures, alongside the Burmese pro-democracy leader Aung San Suu Kyi in a series entitled "Securing Freedom".

[41] In her first lecture, titled "Terror", recorded at BBC Broadcasting House in London, she reflected on the lasting significance of 11 September 2001, asking was it a terrorist crime, an act of war, or something different.

She also revealed details of her own role in the discussions involving international security agencies in the days following the attacks on New York and Washington DC and examined the impact the US-led invasion of Iraq had on the fight against al-Qaeda.

[42] In her second lecture, titled "Security", recorded at the Leeds City Museum, she stated that the use of torture is "wrong and never justified" and should be "utterly rejected even when it may offer the prospect of saving lives".

She said that the use of torture had not made the world a safer place, adding that the use of water-boarding by the United States was a "profound mistake" and as a result America lost its "moral authority".

[43] In her third and final lecture, titled "Freedom", recorded at the British Library in London, she discussed foreign policy priorities since the September 11 attacks.