The story of Deep Throat was well-known, but what lurked behind the identity of Deep Throat was not. This was not a lone whistle-blower being protected by a courageous news organization; rather, it was a news organization being used by the FBI against the president, […].

The story began on 17 June, 1972, when a group of men were caught breaking into the Watergate complex in Washington DC. They were attempting to plant listening devices in the offices of the Democratic National Committee.

Robert Smith says that two months later — on his last day at the New York Times — he had lunch with the acting director of the FBI, L Patrick Gray.

In an interview with the BBC, Mr Smith recounts how Mr Gray began divulging details of the Watergate break-in, a range of other illegal political activity, and the Nixon administration's attempts to cover it up.