Panorama | How Many More Skeletons

In this report from a longer programme, Tom Mangold speaks to Leo Long, one of the men whom Anthony Blunt recruited into his Cambridge spy ring. Though he made a full statement to MI5 in 1964, Long's case was never presented for prosecution, which raises the question of whether other possible traitors were given free pardons and on whose authority they were granted. In the studio, David Dimbleby invites shadow Home Secretary Roy Hattersley to discuss the issues surrounding the case.

The 'Ring of Five' was first exposed by Anatoliy Golitsyn during his defection from the KGB in 1961. Golitsyn identified Donald Maclean, Guy Burgess and Kim Philby. Although Anthony Blunt confessed to being a spy in 1964, implicating 12 former associates (including Leo Long) in the process, his involvement in the spy ring wasn't made public until 1979. At this point, Prime Minister Margaret Thatcher, prompted by allegations from a journalist, confirmed that this had been known to MI5 for some time.