The founding principle of the medical profession, although not actually appearing in the Hippocratic Oath, is often said to be this simple phrase: “First, do no harm.”

And although we don’t have an equivalent in education, I think we assume that not doing any harm, not undermining the opportunities and provision of children, should be a sacred principle in our sector, too.

Despite the fragmentation of education, the atomisation of schools and colleges, the watering-down of a national mission, “do no harm” has been there, sometimes battered and denigrated, but a presiding collective moral principle.

I’ve been thinking about this since I read about a speech being given by schools minister Nick Gibb yesterday to heads of grammar schools. Now, I represent the leaders of many of the 163 grammar schools in England, and they are good people doing good work. But I suspect many of them will have felt as squeamish as I did when they heard Mr Gibb’s pronouncement.

According to a preview of the speech leaked to the press, the schools minister thinks that grammar heads should take responsibility for attainment in some neighbouring schools. In the most extreme cases, they could take over the leadership of schools in special measures. They could also create their own non-selective schools and impose a “grammar school ethos” on them.

The Mail reported that he was due to say: “Collaboration between schools can add momentum to raising education standards, as we have seen with the growth of high-performing multi-academy trusts. I would like to see more grammar schools engaged in this type of work, which we know can be mutually beneficial. Through these partnerships, even more pupils will benefit from those qualities that define grammar schools.”

‘Patronising non-grammar schools’

I certainly agree that mutually supportive collaboration is beneficial. But the government’s obsession with grammar schools and their ethos as the key to raising standards is patronising to other schools and is not based on any evidence.

A headteacher phoned me last week on this subject. He’s in a town with a long-standing grammar school. And he’d heard from one of his school’s parents that she’d got notification of a public consultation from the grammar school. It was thinking of increasing its roll.

In one sense, there’s nothing surprising about this. Despite the evidence that increasing selection will not raise standards or increase social mobility, the Department for Education recently announced £50 million to expand existing grammar schools.

As one Conservative MP put it to me: “This is Number 10 trying to throw some red meat to keep the Tory shires happy.”

The education secretary’s own justification was built on an oddly framed concept of fairness. Other schools, he pointed out on BBC Question Time last week, were allowed to apply to expand, so why not grammar schools? Why should they be victims?

Except that expanding selective schools isn’t the same as just expanding any schools. It has different consequences.

That’s what this headteacher was explaining to me. In a long-term headship, he and his team of teachers and leaders have created a successful, popular community school in which parents don’t have to worry about whether they should be paying for private tuition towards the 11-plus test from the age of 7 - something which happens on an industrial scale in areas of deep-rooted selection and which, by definition, favours parents of higher income.

Now, he says, he knows what will happen next. If successful in its bid for funds to build an annexe to house another couple of classes, the grammar school will need to find its new pupils from somewhere. They’ll come, of course, from existing neighbouring schools - good community schools, well-liked by parents.

‘Squalid’ policy-making

And the consequences of this squalid bit of policy-making are likely to be devastating. For all its rhetoric that any grammar school expanding must include “ambitious and deliverable” proposals to increase access for disadvantaged pupils, the actual impact is easy to predict.

A scramble will happen whereby aspirational parents do all they can to get their child into the grammar school. The funding to other schools will inevitably decline as the academically brightest pupils leave spaces behind. Thus there will be less money available for a smaller pool of students, some of whom will be thinking that they now attend a second-best school.

The idea that grammar schools should then be picked out to take responsibility for neighbouring schools adds insult to injury.  

Of course, the government’s belief is that all of this will drive up standards. But its rhetoric is likely to convince very few, including an increasingly anxious parent body who want nothing more than for their child to attend a good local school.

Which is why I feel so depressed about this bit of policy-making - trivial in its proportions but significant in the depth of its contempt for any research base.

The medical profession has been far better than education at heeding the evidence. We should learn from them. Do no harm.

Geoff Barton is general secretary of the Association of School and College Leaders. He tweets @RealGeoffBarton