Our spies must answer to Parliament for their actions

'The indirect impact of Shayler's self-styled patriotic whistle-blowing will be far-reaching'

For a man who shows every sign of early canonisation as the liberals' summer hero, David Shayler is a less than wholly credible figure. The most sensational of his outstanding claims - that MI6 plotted, whether with the connivance of Robin Cook or not - to assasinate Colonel Gaddafi isn't borne out by the evidence he has so far made public. What the document he has posted on the internet does show is that the service was in contact with dissidents who reported the possibility of an assasination. Which is hardly the same thing and suggests - unless Shayler has a lot more to tell Special Branch - that they were doing little more than their job.

For a man who shows every sign of early canonisation as the liberals' summer hero, David Shayler is a less than wholly credible figure. The most sensational of his outstanding claims - that MI6 plotted, whether with the connivance of Robin Cook or not - to assasinate Colonel Gaddafi isn't borne out by the evidence he has so far made public. What the document he has posted on the internet does show is that the service was in contact with dissidents who reported the possibility of an assasination. Which is hardly the same thing and suggests - unless Shayler has a lot more to tell Special Branch - that they were doing little more than their job.

Secondly, I may be naive, but I find it hard to believe that even the stupidest MI5 operatives became convinced that Jack Jones, a notably frugal man who played a central role between 1976 and 1978 in containing the extra-parliamentary forces that threatened a democratic government led by Jim Callaghan, was a KGB agent.

This doesn't, however, mean that he will necessarily be convicted by a jury of a breach of the Official Secrets Act. Whatever the merits of the Act, the Government has little choice but to prosecute. In other circumstances it would be hugely tempting to make a deal by which Shayler agreed to shut up in return for dropping prosecution. But that option is almost certainly off the map, not least because Shayler and his astute lawyer, Liberty's John Wadham, want to test whether the Act - and its exclusion of a public interest defence for people in Shayler's position - conforms with the Act, coming in in October, incorporating the European Convention of Human Rights. And they can only do that if Shayler has his day in court.

Fair enough. Both Shayler's case - and the more imminent one in which the former military intelligence officer Nigel Wylde is being prosecuted for information given to the writer Tony Geraghty - will help to provide that test. Nor is the outcome, at least in Shayler's case, a foregone conclusion. The courts will have to decide between the competing claims of freedom of speech and reasonable confidentiality, between public interest and private duty. But it will be an important case nevertheless.

But the indirect impact of Shayler's self-styled patriotic whistle-blowing, I suspect, will be more far-reaching. For as in previous cases, the effect will surely be to increase the pressure for greater accountability and scrutiny of the security services. The argument is simple, the more such open scrutiny exists, the less the Shaylers are in a position to make waves with the information at their disposal.

To the credit of both this Government and the previous one, quite a lot has changed in the way the security services function. Not only are they now publicly avowed, but there is at least an element of parliamentary scrutiny in the albeit heavily constrained Intelligence and Security Committee of MPs - one which stops short of full Select Committee powers. Whereas previous Labour home secretaries were probably content for MI5 to keep an eye on recalcitrant left wingers - including in his youth the present Home Secretary, Jack Straw - that era has probably gone. Moreover, Straw has realised the leverage afforded to the Home Office by its being able to tell the security services that it - and the home secretary - has from time to time to go before the committee. And in the enquiry into the Mitrokin revelations, Straw ensured that the ISC was able - as it had originally been intended not able - to examine at least some operational matters.

The question, however, is whether it is enough. Roll the clock back to June 1999 when the Home Affairs Committee, chaired by Chris Mullin, now a minister, recommended that a full Parliamentary Select Committee with normal powers to call evidence, should be given the job. By far the most striking evidence to the committee was that of David Bickford, who argued eloquently for just such scrutiny. Mr Bickford was adamant that the services had nothing to fear from US Congressional committee-style oversight. It could be a headache for the services at times; but in the end it would be in the services' interests to be examined that way - both on strategy and in cases where absolute national security was imperilled on operational matters. What made Mr Bickford's evidence rather credible was that he had recently retired as legal adviser to both MI5 and MI6.

For there remains a good deal we don't know - some of it rather more interesting than Shayler has come up with. To take just one example, as Lord Justice Stuart-Smith, the outgoing Intelligence Services Commissioner, pointed out in March, MI6 is involved in more than mere national security or the ever internationalising campaign against organised crime. The Intelligence Services Act of 1994 "reflects the importance of the SIS role in in obtaining and providing information in support of the UK's economic well-being".

Now, this may be no bad thing, especially post-cold war. When the focus of so many British interests is wrapped up in negotiations with its European partners, for example, it may make a good deal of sense to have the best advance intelligence possible about the negotiating stances of those partners, particularly if other countries' intelligence agencies are providing similar services. Perhaps we should never know the operational details - like whether this occasionally involves a quick briefcase swap in the cloakroom to rifle through another government's papers. But the wider questions surely are worth debating.

A rather better idea of what the security services provide for their money - and a breakdown of the broad headings under which it is spent - is probably in the interests of the services themselves. Which is one of the reasons, I suspect, why Mr Bickford commented in his written memorandum to the Home Affairs Select Committee - in arguing for Select Committee oversight - that "strategic planning [by the intelligence services] is best served by outsiders asking difficult questions". And that's all the truer now that the simplicities of the cold war world, so vividly chronicled by John Le Carré, no longer apply.

For several generations many British field operatives, especially in the Security and Intelligence Service, have been outstandingly brave and intelligent men and women, taking great risks for their country and inevitably receiving little or none of the public recognition lavished on much lesser contributions made by other representatives of the UK abroad. Indeed the SIS at its best, not to mention GCHQ, is no doubt one ofthe ways in which Britain - to usethe old cliché - punches above its weight internationally.

But that isn't in itself a case against greater transparency and oversight, as the most imaginative and progressive members of the security services have long recognised and as Bickford emphasised two years ago. Shayler is hardly a historic figure. But he will probably give the services another little push down the road to glasnost. A proper Select Committee would surely be the first step.

d.macintyre@independent.co.uk