This emerged in the run-up to today's Commons debate, when the Government will again make clear its opposition to an amendment on public benefit that the commission has said it favours.
The amendment from Labour MP John Grogan would require the commission, which will run the public benefit regime when the Bill becomes law, to consider 'undue restriction' - such as fees - on obtaining public benefit.
Andrew Hind, chief executive of the commission, said charities already had to define outcomes for beneficiaries in trustees' reports. "How much tweaking does that need to become a report on public benefit?" he asked.
"What does the link look like between the value of tax breaks and the things they're doing for society?"
The commission briefed MPs and peers last week on its plans for public benefit, such as an advisory group chaired by Professor Albert Weale of the University of Essex and a citizens' forum.
Hind said: "We let it be known we wanted the amendment because of underlying uncertainty in case law. We were less strong in saying that it's our job to get on, professionally and vigorously, in acting on whatever Parliament decides to put in the Act."
- See Editorial, page 13.