Subject not named by the BBC appears to be Alistair McAlpine, who is either a Baron or a Lord, depending on which poorly sourced website one consults.

His Wikipedia page confirms the details from the BBC: he was a high-ranking Tory under Thatcher: http://en.wikipedia.org/wiki/Alistair_McAlpine,_Baron_McAlpine_of_West_Green

Also, sketchier sources say that the Welsh boys home where he preyed on boys was used by British Intelligence to offer boys to foreign diplomats in order to secretly film them for blackmail purposes:
http://www.whale.to/c/north_wales_paedophile_ring.html

Here's the link I saw that officially links McAlpine to the BBC story, but keep in mind, this website, Topix, has zero credibility because anyone can create an anonymous account and say whatever they would like. So, by itself, not convincing, but if it causes a major news outlet to come forward with its claims, then that's a big deal... but so far, it's only this:
http://www.topix.com/forum/world/united-kingdom/TI0V8BPDVK4BKJPHG
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