The National Association of Governors and Managers disputed Hackney council's view that it has little power to act in the case of Jane Brown, the Kingsmead School head.
Hackney argues that the Government's policy of delegating power to school governing bodies means it can do little about the governors' refusal to accept its advice and suspend Ms Brown.
But Walter Ulrich, the association's spokesman and a former senior civil servant at the Department for Education, said: 'That is a smokescreen. It isn't the case that the local authority is now powerless to see that right is done in its own schools. It has very substantial powers.'
The council had the legal right to insist on a report from governors on the allegations against Ms Brown, who turned down a school trip to the ballet Romeo and Juliet because it was about heterosexual love.
He said a council could withdraw a school's delegated budget, though this was unlikely unless the governors had messed up all their responsibilities. Hackney could also ask for a judicial review of the governors' actions. Finally, it could ask John Patten, the Secretary of State for Education, to declare the governors had acted unlawfully or unreasonably. The council is investigating alleged irregularities in Ms Brown's appointment.
Government critics say the case exposes the flaws in legislation under which the local authority employs teachers, but the governors are responsible for disciplining and hiring and firing them.
Heads were told by their union yesterday to mark this year's tests for 7 and 14-year- olds. But the National Association of Head Teachers warned that the tests may not take place in some schools because some teachers are continuing last year's boycott. Heads who feel test results in their school would be incomplete and therefore invalid would be justified in cancelling them.