Public confidence in exams will be threatened unless the new regulator is given more teeth to resist ministerial interference and intervene over standards, exam boards warned this week.
Two of the big three awarding bodies are concerned, for different reasons, that Ofqual will lack the power and autonomy needed to bolster faith in the assessment system when it becomes operational.
Cambridge Assessment, parent company of the OCR board, argues the legislation to set up the regulator would give ministers too much scope to interfere in its work and hinder its independence.
AQA believes the public could start to believe that equivalent qualifications offered by different boards have varying degrees of difficulty unless Ofqual gets clearer powers to intervene in and rule on such matters.
Mike Cresswell, AQA's director general, says the potential for disputes between boards over the standards they each set is increasing. This is partly due to big structural changes that are imminent.
His warning came as it emerged that Kathleen Tattersall, chair of Ofqual, has admitted that neither the regulator or exam boards are clear about how they should maintain standards when new qualifications are introduced.
Qualifications and Curriculum Authority board meeting minutes from September say that Ms Tattersall noted the need for Ofqual and the boards to, "arrive at a clearer picture of what is meant by `maintaining standards' when the structure of qualifications changes".
Ofqual already exists as a committee of the QCA, but it will not become an independent regulator until the Apprenticeships, Skills, Children and Learning Bill, being debated in Parliament for the first time on Monday, becomes law.
Cambridge Assessment said it was concerned about clauses giving the Schools Secretary decision-making powers within Ofqual's remit. Potentially, ministers will have a say over the specification of a qualification, appointments to the regulator's board and on capping any exam fees Ofqual introduces.
Explanatory notes suggest how these ministerial powers should be limited. But Cambridge Assessment is concerned that such checks will not be statutory. Simon Lebus, its chief executive, said: "Unless there is a good deal of detail around these things, they can end up representing a licence to interfere. We think there is potential for the independence of the regulator to be compromised."
Mr Cresswell says Ofqual needs the power to rule on specific exam standards to counter perceptions of dumbing down. He says the pressure for schools to climb league tables is leading to more claims that a qualification from one board is easier to pass than that from another.
Both boards want to see stricter, more detailed rules on how Ofqual reports back annually to Parliament and the Government.
Ed Balls, the Schools Secretary, said the bill would, "provide for Ofqual to be a genuinely independent regulator". He intends to agree with Ofqual a memorandum of understanding that would allow ministers to decide minimum requirements for qualifications without compromising the regulator's independence.