The Charity Commission has been "pulled into second-guessing and micro-managing trustees' decisions" because its guidance on public benefit is too vague, the Independent Schools Council argued in a tribunal hearing yesterday.
The hearing in the Upper Tribunal (Tax and Chancery) aims to determine whether the commission's guidance on how fee-charging schools can show they provide a public benefit is based on a sound interpretation of charity law.
Nigel Giffin QC, representing the ISC, said: "The commission's test of whether you've done what is reasonable or appropriate in the circumstances [to provide a public benefit] is so vague and so uncertain that it leaves trustees wholly unable to say with any reasonable degree of certainty what they must or must not do in order to avoid being in breach of trust.
"It has the consequence that the commission gets pulled into second-guessing and micro-managing trustees' decisions about how to perform their duties and run the charity. That is what has been seen in the public benefit assessments that have been carried out and that is why we are here."
Giffin said the commission had been "drawn into taking trustees' decisions for them in a way the Charities Act 1993 says it is not the Charity Commission's function to do".
He was asked by Mr Justice Warren, leading the panel of three legal experts that will rule on the case, about the requirement in the Charity Commission's guidance that the benefits of a charity must be balanced against any harm or detriment its activities create.
Giffin replied: "Where you have, in effect, differing political or social views on whether independent schools promote or restrict social mobility, that has to be put aside for what you can sensibly adjudicate on with evidence."
The commission, the Attorney-General and the two intervening parties, the National Council for Voluntary Organisations and the Education Review Group, are due to put their case to the tribunal later this week.