Jane Brown, the head of Kingsmead Primary School in Hackney, east London, will take up her post in September as an additional inspector of primary schools for the Office for Standards in Education (Ofsted).
Ms Brown could be sent to inspect any school in the country and will be responsible for reporting on children's "spiritual, moral, social and cultural development".
Two years ago, she sparked a furious row when she rejected free tickets for a performance of Romeo and Juliet. Conservative politicians and press presented her decision as a typical example of "loony leftiness" in a Labour-run authority. John Major called it "a deplorable example of political correctness".
Gus John, director of education for Hackney, recommended Ms Brown's suspension, but governors and parents resisted.
An Ofsted spokesman said last night that Ms Brown's past would not affect her new role, and that she could not bring "ideological baggage" to the position. He said: "I don't see that what may or may not have happened in the past will affect her judgement. Clearly she is a highly experienced teacher, and that is why she was appointed."
Inspectors, he said, could not change anything in the schools they inspected. "They can only report back."
Ms Brown was one of 174 inspectors taken on by Ofsted because it was falling behind government demands for more frequent school inspections.
The body has caused much resentment among teachers, who accuse it of following a government-led agenda to denigrate teachers and force a return to traditional teaching methods.