When I wrote it, I thought I was going to be extradited to stand trial.   As such I saw it as an opportunity to make a veiled threat to the intelligence services.

Read the Sunday Telegraph's coverage of it at the link on the right.

So you finally have me where you want me - locked up, virtually silenced and denied the rights normally granted to prisoners in the French penal system - visitors and a word processor.

But what purpose does this serve anybody? I don't relish the prospect of serving up to a 2 year sentence, especially not for telling the truth and speaking out in the public interest. And the Attorney General can stop the proceedings against me now if he decides they do not serve that public interest.

I understand that you fear that might send out the wrong message to other intelligence officers and open the floodgates to a series of whistleblowers. That stance reveals a number of interesting points.  First, it shows that you are very worried about demoralised officers in MI5 and the problems they might reveal that lie at the heart of the service.  Second, it reveals a certain perversity. Anthony Blunt, a KGB agent who betrayed his country, was granted immunity from prosecution. In other words, a whistleblower has to be prosecuted when a spy and traitor is not. What sort of message does that send out to the average MI5 officer?

But it doesn't have to be like this. You and the government could take this opportunity to reform the Officials Secrets Act (OSA), which is looking increasingly outdated and regressive in a modern democracy. Of course you have to be able to investigate threats to the state in total secrecy. But, if you think that the OSA represents the correct balance between that fundamental requirement and the freedom to criticise and hold to account a deparment of State, you display how little respect you have for civil liberties.

I'm sure the many people I worked with in the intelligence community, whose respect I gained, will feel very uneasy about the prospect of a former officer and friend being imprisoned for speaking out in the way they themselves would like to.

Rather than be encouraged to give away secrets, in the event of me not being prosecuted, they would more likely be grateful for a change in legislation which would allow them to hold their bosses to account - without their concerns that their careers would be ruined.

I suggest therefore that the OSA is modified to allow potential whistleblowers to take their concerns to an independent body which would examine them and then report publicly on their concerns, wherever possible. We also need to define which types of information - which when revealed - would constitute a real threat to national security.

The full weight of the law could then come down on officers who disclosed information without regard for either of these provisions. This is not radical stuff. It is the policy adopted by Western nations with regard to their intelligence operatives. Given the nature of the global media and the Internet, it is also imperative that you can take steps against those who genuinely threaten national security by making unauthorised disclosures.

I am awaiting a judgement on extradition but it is by no means clear that I will be extradited because the OSA would be illegal in any country whose constitution guaranteed freedom of expression. And for an extradition application to be successful, the extraditable offence has to exist in both the countries involved in the process. An OSA reformed along the lines I have outlined above would circumvent this problem.

As I sit here in my prison cell, I can't help feeling that my only mistake was being too open with you. After two government bodies refused to take my evidence, including the details of the Gadaffi plot, I told you I intended to put my disclosures on the Internet. I didn't want to do this but I couldn't see how else I could encourage you to take that evidence.

On the subject of the Gadaffi plot, it is imperative that you take the evidence of the other two MI5 officers who were briefed about it as soon as possible. You know who they are. You should then submit their evidence to government ministers. Any other action would smack of a cover-up and an attempt to pervert the course of justice.

In the spirit of openness, you might also like to inform the media when the above two steps have been completed. There are absolutely no good reasons for not making this public. The government will then have to conduct an independent enquiry which, I'm sure, will vindicate me.

This will, of course, make it more difficult to persaude a jury to convict me, even though I have no technical defence under the OSA.

To delay an enquiry until after any trial in order to make it easier to secure my conviction has to be the most dubious argument for prevaricating over my disclosures on the Gadaffi plot. It is secrecy for political convenience, an intolerable abuse of power.

But what if I am eventually convicted? You cannot put me behind bars forever. One day I'll be free again and what are you going to do then? Given my treatment, many might then resort to the simple tactics that could really cause you serious problems. I am not in that game and never have been.

But what will you do, once I am free again? Spend a fortune on sending Special Branch officers across the world to keep tabs on me, as has happened with Richard Tomlinson, the ex-MI6 man?

Surely, you have better things to do with the shrinking intelligence budget, like protecting those who provide that money - the taxpayer - from terrorist atrocities.

My prosecution and persecution serve nobody's interests, least of all yours. You would be better off using this situation as an opportunity to demonstrate to the public that you can be reasonable, responsible and capable of good judgement.

So stop your prosecution of me and reform the Official Secrets Act.

Regards Prisoner 269151F