Ofsted has rejected claims that it is the lapdog of the Government, in reponse to a pamphlet calling it Tony Blair's enforcer.
Inspection, Inspection, Inspection by Anastasia de Waal, published by right-of-centre think-tank Civitas, claims inspectors have done little to raise standards, instead enforcing Mr Blair's political control of the classroom.
She said learning comes second to tick-box inspections which check pointless paperwork and progress towards artificial targets. The Government is now using Ofsted to impose its agenda on private schools whose freedom from new Labour dogma has enabled them to achieve higher results, she added.
The pamphlet calls for an independent ombudsman to monitor principles on which inspections are based and for serving teachers to be part of inspection teams to reduce political interference in schools.
"Ofsted acts as the enforcer for the Department for Education and Skills, making sure that all schools and all teachers are doing whatever the latest (and ever-changing) fads in Whitehall dictate.
"Ofsted was set up in 1992 under the Major government to maintain standards in schools. New Labour reformers have seized this powerful mechanism and added their own brand of intense managerialism, awarding themselves a monopoly over the definition of excellence in education, then enforcing their demands through detailed prescription of teaching methods."
She says that since Ofsted began inspecting independent schools in 2003, it has subjected them to the same bureaucratic intervention as state schools.
"The result can only be to undermine their effectiveness - and thus achieve Blair's stated aim of closing the gap (with state schools)."
She said that private schools have a lot to fear from a bad Ofsted report, which can have a devastating effect on their finances, as parents send children elsewhere or sue the school.
In the state sector, she said, rising results are due to teaching to the test and easier exams rather than a real rise in standards.
And a "climate of fear" is preventing teachers and governors in both state and private sectors speaking out about their concerns.
An Ofsted spokesperson said: "We believe the Civitas book is inaccurate and based on limited enquiry. We do not agree with the main arguments.
"Ofsted is not a lapdog of the Government, as reading any of our reports or publications will demonstrate. We report without fear or favour based on the evidence we see in schools. For example, our recent report Safeguarding children: an evaluation of procedures for checking staff appointed by schools made a series of robust recommendations for the Government."
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