But the wiretaps of the conversations of Mario Scaramella show him and Litvinenko as key players in a cynical transnational disinformation operation.  Involved in this somehow is the Soviet-era defector Oleg Gordievsky, whose case officer when he was KGB resident in London was the current head of MI6, Sir John Scarlett.

Clearly, the Italian evidence needs to be put together with an exploration of Litvinenko's activities in what the veteran American investigative journalist Edward Jay Epstein has called the 'shadowy world of security consultants' in London.

The radiation trail which is supposed to establish that Andrei Lugovoi deliberately poisoned Litvinenko, Russian investigators claim, may actually derive from a leak at one of the companies the two visited, Erinys International.  According to Lugovoi, another company they visited, RISC Management, acted as a front for MI6 in attempts to recruit him to help secure compromising information on Putin.

These claims may -- as British 'security sources' have suggested -- be a smokescreen.  But in the light of the cogent critique made by Epstein of the official British version, one cannot take this for granted.  And this is all the more so given that, as I noted in my previous diary, Gordievsky's accounts strike at the basis of the British case.

An investigation of Litvinenko's activities in the 'shadowy world of security consultants' -- or as they are more generally known, private security companies -- may perhaps then cast light on how he came to die.  

It also brings us up against more general issues.  The American anthropologist Janine Wedel uses the terms 'flex groups' and 'flex players' to refer to organisations and individuals which manoeuvre between public and private roles, in so doing relaxing government rules of accountability, and business codes of competition.

Whether or not Lugovoi's claims about Erinys and RISC stand up, it is clear that the history of the two companies is involved with some particularly interesting 'flex players'.

A story by Cathy Scott-Clark and Adrian Levy in the Guardian in January called this assumption in question, suggesting that Litvinenko may have been murdered as a direct result of his activities in Italy. But their account presupposes that the British request for the extradition of Andrei Lugovoi to face trial for Litvinenko's murder is backed by compelling evidence.

According to the official British version, the radiation trails left by Lugovoi establish beyond reasonable doubt that he deliberately poisoned Litvinenko in the Pine Bar of the Millennium Hotel in Mayfair. But painstaking work by the bloggers AJStrata and copydude, and the veteran investigative journalist Edward Jay Epstein, has called in question both the strength of the evidence behind the indictment, and the good faith with which it was made.

In a post on 'Russia Blog' I have pointed to the extraordinary way in which Gordievsky and the London-based ex-Russian military intelligence operative Boris Volodarsky have been undermining the official British case.

Whether in smearing Berlusconi's opponents Gordievsky was acting in conjunction with elements in British intelligence remains unclear.  In insisting that Litvinenko was not poisoned in the Pine Bar, but at another meeting earlier the same day, however, Gordievsky is cutting the ground from under the official British version of how Litvinenko died.  So although some of what he and Volodarsky have claimed is clearly itself disinformation, it is worth exploring the possibility that some of what they say may be true.  

Doing so may help us get closer to understanding how Litvinenko died.  And it brings us up against a range of issues concerning the ambiguous relations between public and private institutions in what Epstein terms the 'shadowy world of security consultants'.  This obscure world, which has mushroomed in recent years, is one on which more light badly needs to be shed.