Clare Short: I quit because this is not a Labour government

I'm afraid the reality is that I have lost confidence in Her Majesty's Government. This is very sad. The opportunity of 1997 was as big as that of 1945. Under Neil Kinnock and John Smith, Labour had prepared itself for power as a modern social democratic party. Tony Blair brought extra gloss, but we were set to win. New Labour has done a lot of rewriting of history.

The Government did reasonably well for the first three years. The rot set in with the second term. Blair had become more confident and did not want his legacy to be spin and focus groups. When I left the Government over Iraq I assumed there would be great debate in Parliament and party to hold Blair to account, and to start to put things right. I soon found that the system was broken.

Then came top-up fees and the unwillingness to consider other options, such as a graduate tax. I was seeing more and more asylum-seekers at my advice bureau and it became clear that the system was a mixture of cruelty and incompetence. The endless targets, initiatives and reorganisation of health and education were undermining much of the good the extra money was doing. Criminal justice policy was dictated by the tabloids. Then came plans for mega-casinos to regenerate poor areas. And even more seriously, control orders and proposals for 90-day detention. The rhetoric of the "war on terror" was inane. The policies exacerbated the problem.

Increasingly, I voted against the Government and was saddened as the Labour conference became a rally for the leader. I returned to the back benches expecting to use the Commons to make my case but found it transformed. All bills were guillotined. Ruthless use of the whips' power crushed the spirit of the Parliamentary Labour Party.

My unhappy relationship with the whips started early. Hilary Armstrong, Chief Whip, made threats. She said I must not say that we were spying on Kofi Annan, nor that Tony had deceived the country by taking it into war. Because I would not agree, I became a pariah.

I considered not standing in the 2005 election but friends were sure the party would recover and convinced me I should stay. Sadly, there was no fightback. Gordon Brown was increasingly diminished and forced to say he supported all that Blair had done.

Then Brown backed the commitments to a renewal of Trident and nuclear power without any serious debate. It seemed nothing would change. At the Hay book festival this year, I said there was a high likelihood the next election would produce a hung parliament that could give us a changed electoral system; then all such questions could be reopened. The Chief Whip wrote to say I was not allowed to say this because it would mean Labour MPs losing seats.

There were constant stories in the press to say I was to be expelled or punished in some other way. I decided not to stand in the next election and thought that, with just a couple of years to run, the whips would leave me alone. Then, while I was Addis Ababa trying to help an NGO that was in trouble, I received media calls about a public rebuke from the Chief Whip and threatening letters saying that informing the whips of my visit did not mean I had permission to go. It seemed they planned to prevent me speaking at the lectures and meetings I had committed to, and that a stream of rebukes was inevitable. The elastic snapped.

This is not a Labour government. And I have no confidence in it. The right thing to do is resign the whip and sit as an independent Labour MP. After 23 years in the Commons and 36 in the party, I have decided to use my last couple of years to speak freely. Many of my constituents have spent the weekend telling me that I should not go, but when I say that I will be there until the next election they are more content.

Our political system is in trouble. The Middle East is burning. I feel very sad that my relationship with my party has ended up like this. But electoral reform is the key to fixing our politics and changing our country. There is no point in being in public life if you are not allowed to speak.

Clare Short is MP for Ladywood