The Silent State, by Heather Brooke, published by William Heinemann.

In writing this wonderful book, Heather Brooke planted a giant bomb under the British parliamentary system.

After years of diligent enquiry, blocked at every point by the Speaker and Commons officials, it was Brooke who forced into the open the squalid details of the systemic theft of public money by our venal and greedy MPs. As a direct result of her efforts, four MPs were faced with criminal charges, dozens more have been forced to resign their seats, and the stench of corruption that encompassed Westminster has been partly lifted.

It is not a coincidence that Heather Brooke is an American journalist. For far too long we British have been ready to accept the bureaucratic culture of secrecy which surrounds Westminster and Whitehall as part of the natural order of things. This book records Brooke's sense of amazement and outrage that facts that would be naturally open to democratic inspection in the U.S. were treated as state secrets in Britain. But she also discovered something extremely sinister. The British state does not merely keep secret vital information that every citizen ought to be able to access in a modern democracy. It is also intruding deeper and deeper into the lives of ordinary citizens.

In the early sections of this book Heather Brooke documents the monumental scale of this government surveillance. She reveals that at every stage of our lives the British state is quietly collecting data it can use against its citizens, starting from the day we are born.

'Schools are not simply for learning,' she records, 'but are becoming factories for social engineering.' And yet Heather Brooke demonstrates that the Whitehall bureaucrats who spy on us are determined to prevent us finding out about them.

Brooke suggests there is a disturbing double standard at work here. She devotes an eye-opening section of the book to a demonstration of how the culture of anonymity in Whitehall is used for malign ends. In one telling example she shows how the names of Ministry of Defence officials who broker arms contracts was kept secret from British enquirers - but made available for foreign contractors.

When the indefatigable Brooke finally obtained an MOD staff directory, the likely reason for the secrecy emerged. Of approximately 450 officials working in defence sales, no less than 161 - approximately 40 per cent - worked specifically on what was listed as the 'Saudi armed forces project' across Britain and the Middle East. This at a time when the Saudi connection was the subject of a criminal enquiry.

Again and again she drives home the message that 'public servants must accept that in a democracy official information belongs to the people - not politicians, not civil servants, not the monarchy.' She tells the fascinating story of how the Commons authorities fought a brutal battle to prevent MPs voting records coming out into the public domain - and threatened legal action for infringement of Parliamentary copyright.

Only after a long struggle did the website theyworkforyou.com, which enables voters to reach an independent judgment on the work rate and record of MPs, come into existence.

Heather Brooke tellingly compares the culture of secrecy and buck-passing amongst British officials with the openness and transparency in her native U.S. She informs us that she grew up in Seattle where 'not only can residents find out who is in charge of various departments, they can drill down to see who is collecting their rubbish, who sweeps the streets, who is enforcing dog control ordinances or even collecting potholes.'

She argues that bureaucrats would actually benefit from an end to the British culture of secrecy: 'It keeps the worst people in the most lucrative, high-end jobs while the best go unrewarded, often punished for speaking out.'

Brooke is regarded as a left-wing journalist who works for the subversive broadcaster Channel 4 and the scurrilous magazine Private Eye. Yet reading this book I realised that she is arguing a profoundly Conservative message. She warns against the power of the big state and values individual freedom above all else, concluding with a warning:

'The issues in this book all grow from a single tragic belief that the public can't be trusted. The corollary is that the state can... History shows the opposite to be true: individuals on their own do less damage than individuals hidden behind the walls of a faceless institution.'

This is a Tory insight and if David Cameron has real courage he should make Heather Brooke's radical agenda his own. She is a great heroine of British democracy who must be celebrated.

This article was originally published in The Mail Online.