Andy McSmith: Forget ex-PMs – the really juicy stuff comes from the back benches

Prime ministers' memoirs promise more than they deliver. A prime minister knows so much more about his time in office than the commentators or lesser politicians who have gone into print before him, and the millions that publishers pay to secure the rights to the memoirs, the hype, the interviews, the news reports and the leap into the best-seller lists, all suggest that the man who was at the epicentre of power is finally telling it how it was. But he never is.

The same is true of political leaders everywhere. Their memoirs are never as revealing or readable as the best accounts by minor players in the political game who have not got big political reputations to protect. The most telling accounts of the Thatcher, Major and Blair years were by Alan Clark, Gyles Brandreth, and Chris Mullin respectively – none of them outstanding as a minister, but all great observers and raconteurs.

It is not that leaders' memoirs contain lies or provable inaccuracies. What these books lack is telling details and illustrative anecdotes that bring facts to life. There is never the self-awareness that reveals what it is really like to hold a position where you are on duty all day, every day, and everything that happens is your responsibility.

Partly this is because a public figure of Tony Blair's stature will have attracted so much criticism and hostility that he will want to defend himself rather than risk writing anything that will open him to renewed attack. Putting up a defensive shield is not the best way to make contact with an audience.

But the former prime minister is not going to provide the kind of intimate autobiography that makes you feel he has shared with you his private experience of public office. This is because the extraordinary pressures of the job cut off those who did it from normal human contact. A serving prime minister has no time for private thoughts. He must always remember that he is on parade.

Tony Blair was never caught out making a damagingly revealing remark. He is so practised in the stilted language of a professional politician that he probably dreams in New Labour Speak.

Someone who has subjected himself to that discipline for so long cannot be expected suddenly to drop his guard in his memoirs to reveal his inner self, if one still exists. His memoirs are bound to read like a series of position statements on what happened in the Blair years rather than frank recollections shared with people he can trust.