So the Green Paper is called Making schools work for everyone. Hardly something one can find fault with.

One of the ways in which the Prime Minister wants to achieve that lofty goal is by allowing faith schools to fill up exclusively with pupils from its own faith group. That would abolish the old 50 per cent cap - created, of course, to ensure diversity and to prevent any sense of “ghettoisation”.

We’ve seen proof of the peril of allowing faith to come before education, particularly when it is a narrow or intolerant interpretation of the belief-set: the so-called Trojan Horse episode in Birmingham schools was regarded by many as a vivid illustration of that very risk.

Theresa May’s plan contains a safeguard: any school seeking to fill itself entirely with adherents of that faith will be obliged to ensure a mix of pupils from different backgrounds.

Pupils won’t qualify for places 

Quite how this will work is hard to puzzle out, however. It will call for tighter wording than merely “different backgrounds”, or we could spend years with court cases and parliamentary enquiries wrangling over its interpretation. Alternatively, we might witness faith free schools doing entirely as they please: but, notwithstanding their many freedoms, they remain subject to government controls and are certainly not absolved of their moral obligations to their setting and wider community.

Yet how can a 100 per cent faith school hope to encompass pupils from a variety of backgrounds, even if it wants to? It might, to be sure, be able to boast a range of socio-economic backgrounds (though critics of faith schools would seldom credit them with that virtue).

Yet how can, for example, a Catholic primary school in a culturally diverse city reflect its setting? If, as in many UK conurbations, there is a significant minority of Indian or Pakistani origin, those families will most likely be Sikh, Muslim or Hindu, and will thus not qualify for a place at that uniquely Christian school.

Picture the reverse: a 100 per cent Muslim school in Bradford or Birmingham will struggle to attract more than a minute proportion of Muslim pupils who are not of Asian provenance.

It’s obvious, isn’t it? But perhaps not to politicians. Either the required safeguard is meaningless - or, if enforced, makes an impossibility (rightly, in my view) of composing a school entirely of pupils of one faith.

As the storm rages simultaneously about grammar schools and selection, and government speaks piously of its desire to achieve social mobility and the best opportunities for all, it seems to me that its faith school proposal could be still more divisive.

Pick-and-mix

Perhaps the best we can hope for is that these wheezes simply won’t work: most of the Green Paper’s ideas are daft (and I haven’t space here to get on to universities and/ or independent schools being coerced into opening new state schools). The raft of new initiatives is reminiscent of a bunch of kids in a sweet shop: our policymakers are indulging themselves with a pick-and-mix of all their favourite ideas - ideas, moreover, designed specifically to appeal to the Tory heartland.

Most of the research into social mobility that we are presented with tends to stem from a particular political or sociological viewpoint. Politicians don’t like research: they merely assert that “they know what works”. Michael Gove, it seems, is not the only politician who despises experts.

I’ve written in the past about “policy-based evidence”: politicians and their allied think tanks are prone to sifting out any research or evidence that doesn’t agree with what they want to believe. As a result, we constantly face piecemeal and contradictory policy proposals that fly in the face of reason - but appeal to the gut-instinct of the party faithful.

Making schools work for everyone is indeed a laudable aim, as I said at the start. Like most ideals, it is probably unachievable in full: but these particular proposals will succeed only in making schools work for fewer children than they do now.

Dr Bernard Trafford is headteacher of Royal Grammar School, Newcastle upon Tyne, and a former chairman of the HMC. The views expressed here are personal. He tweets as @bernardtrafford

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