‘I don’t think we are a charity. We are a successful, multi-national educational institution,’ explained the public school head to me. And he was right. As it happens, he was a highly progressive head committed to using the wealth and resource he enjoyed to collaborate with an under-performing local academy. For the first time, their partner school now had maths graduates teaching physics and a new range of language options. But he had no doubt that he should not be in receipt of charitable status and tax relief.

Which is why one of the few components of Theresa May’s school reforms I can support is the Prime Minister’s determination to introduce ‘stronger, more demanding public benefit tests for independent schools.’ But the reforms which they are consulting on are ill thought through and illiberal. There is a smart way and a stupid way to promote richer and deeper collaboration between the fee-paying and state sector. We set it all out in the 2015 Labour Party manifesto when – surprise, surprise – the Tories accused us of ‘class war’ and ‘dumbing down.’ Now, it is their flagship policy.

The starting point is that collaboration between and amongst schools of all types work. When selection, peer group and class size are removed from the equation (three big omissions), the quality of teaching in the state sector is better than the private. According to Professor Dylan Williams, teachers in the state sector deliver the same quality of teaching in classes of 25 that their private school counterparts deliver in classes of 13. Similarly, on tracking pupil attainment, on Special Educational Needs, on teacher training, there is much that the public schools could benefit from with better partnership.

But we also know that when it comes to playing fields and boat houses, art blocks and theatres, Oxbridge-interview prepping and career guidance, confidence building and network stretching, the public schools continue to have a profound advantage over their state school peers. The scandal, of course, is that these schools benefit from £140 million a year state subsidy thanks to their charitable status and accompanying business rate relief. Whilst Stoke-on-Trent 6 th

Labour’s 2015 plan was progressive and workable: we would allow each private school in receipt of business rate relief to think about its own area of excellence (sports training; history teaching; pottery; lab work) and seek out a collaborative relationship with a nearby school. We were not asking them all to sponsor an academy (which they often were not very good at) or indulge in some patronising noblesse oblige. It was to be a hard partnership from which both schools benefited, and its quality would be judged by the rigorous Independent Schools Inspectorate. If the public schools failed to deliver – or thought opening their gardens; dodgy bursaries; or putting art on the walls was enough – then their business rate relief would be annulled.

By contrast, the government seem to be choosing a far more complicated and illiberal route, which would end up with Ministers instructing the Charity Commission which institution should or should not be a charity on purely political ground. This is a dangerous assault on civil society which could, in the long run, see politically awkward charities like Oxfam or Greenpeace struck off by government fiat. At the same time, they are asking the Charity Commission to adjudicate on the quality of educational partnership between state and private, which they do not have the skills to do.

I think we are now heading towards a political consensus that the state subsidy of private schools in their current form is coming to an end. The Labour party should support that part of the package. Because looking at the reception Justine Greening got in the Commons, they might need the votes.