In December 1966 the Report of the Inquiry into Prison Escapes and Security by the Admiral of the Fleet, Earl Mountbatten of Burma, was presented to parliament. Two months earlier, and two days after the escape of George Blake, Mountbatten had been appointed by the Home Secretary, Roy Jenkins, to conduct an inquiry and to make recommendations. Having accepted the task on condition that his findings would be acted upon, as he was not prepared to waste his time otherwise, he performed it without fuss and with becoming promptitude. This was all the more impressive as, in addition to Blake, he had to deal with twenty other newsworthy escapees, including two of the most notorious – and admired – criminals of the day who in April 1964 had been sentenced to thirty years’ imprisonment for their part in the ‘Great Train Robbery’: Charles Wilson, who three months later had escaped from Birmingham after his accomplices broke into the prison; and Ronald Biggs who had been whisked away from Wandsworth in 1965. Mountbatten also took evidence from a wide variety of sources, visited seventeen prisons, made detailed proposals, and even gave some consideration to Scotland which was outside his official remit.

George Blake was a spy for the Soviets and traitor to his adoptive country. After his conviction in May 1961 under the Official Secrets Act 1911 he was sentenced to forty-two years’ imprisonment – supposedly a year for every agent his betrayal had compromised – the longest determinate sentence ever handed down by a British court. Had he been charged with treason he would have hanged. This was in effect a slow death sentence. He was allocated to a cell in ‘D’ Hall of Wormwood Scrubs where well-behaved long-term prisoners were housed. There this most serious of offenders, and national security risk, was left for five years.