Chris Woodhead, in his appearance before a House of Commons select committee, insisted that his job was to break the "conspiracy of silence" on the problems of inadequate teachers.
In reply to questions, he denied he had ever behaved in a way that could be considered party political. In his 18 months in the post he had only met the Prime Minister once on a one-to-one basis.
It was crucial, he told MPs that around 15,000 teachers should go. Few teachers are ever sacked; there appeared to be a lack of will.
He rejected charges that the 15,000 calculation was based on a biased sample of schools. He also rejected accusations that he had manipulated statistics in his annual report on schools.
He said the former senior HMI Colin Richards, who had made the charges, had ample opportunity to put his case.
"If he says he was not able to put his case, then he was lying," said Mr Woodhead. He was too concerned with other tasks to pursue Mr Richards in the courts.