A recent conversation with a headteacher underlined the fact that the time is ripe for a new vision of how we judge schools, and whether we should judge them at all.

The school leader I spoke to had overseen a significant turnaround in his school’s GCSE outcomes. For a school that was previously judged to require special measures, this was great news. Or at least it would have been had it not illustrated the fallibility of its special measures judgement or had it been given any weight during the school’s subsequent monitoring visit. I’m sorry to report that the school leader has left their job as a result of this experience and the school’s improvements are at risk.

What does this reveal about the limitations of the current accountability framework?

Part of the problem was that the school was judged to require special measures as a result of poor historic outcomes, even though leaders were confident this was about to turn around.

The inspectors had backed their interpretation of the school; it was judged “inadequate”. Shortly afterwards, the next set of GCSE results arrived and showed performance was now “average”. The school’s leadership was vindicated but the Ofsted judgement now looks questionable.

The HMI who arrived some months later for a monitoring visit insisted she was unable to take account of this new data as it was beyond the remit of her visit - she was just there to check in on the school and look at its improvement plans, she explained. Data seemed enough to condemn the school a few months before but was now off the table for discussion.

The school has reason to feel aggrieved. My recent collaboration with DataLab shows that the vast majority of schools with “average” Progress 8 scores (using the Department for Education’s definition) tend to achieve a “good” rating from Ofsted. Only 4 per cent of such schools were judged to be “inadequate”.

This suggests that had the school been inspected after its GCSE results were published, or had inspectors backed the view of the school’s leadership, it was very unlikely it would have been judged to require special measures in the first place.

We know that Ofsted is working on a revised framework for 2019. Whatever else it does, whether it tackles the curriculum or safeguarding, it will fall short if it doesn’t recognise that the stakes are so much higher than when it first started inspecting schools. Too much now hangs on the judgement of inspectors.

Inspection is subjective

Ofsted chief inspector Amanda Spielman noted at the Association of School and College Leaders’ Conference earlier in the year that inspection is not just a science - it is an “art”, too. It consists of two layers of interpretation: the evidence and the framework.

I have some sympathy with inspectors who have to reach valid judgements in the midst of this difficult interpretive exercise. I have even more sympathy for schools and their leaders when it goes wrong.

If we accept that interpretation is inherent in the “art” of inspection, then we have to act to mitigate against the risk of this subjectivity - not by trying to disguise it as science but by ensuring its effects are proportionate.

Ofsted proudly champions its mantra of inspecting “without fear or favour”, but neutrality is no longer enough. The stakes are too high. When so much hangs on a judgement, the judgement should be unequivocally accurate, not just impartial.

But in the absence of a perfectly consistent and accurate system, what is really needed is a new sense of proportionality - both in terms of how Ofsted inspects and how inspection is used within the education system. If we know that judgements are an exercise in subjective and fallible interpretation, why do we place so much emphasis on them?

Some of this is Ofsted’s responsibility and some of it is down to the school leaders, governors and trusts who have been complicit in the elevation of Ofsted judgements to a level that far outstrips their validity.

This is an endeavour that schools should share with Ofsted but the inspectorate must be leading from the front. Rather than trying to reach the “right” judgement, Ofsted may be better off reconsidering whether it should be making a judgement at all. Removing definitive judgements from a subjective process may well free up schools and inspectors to have truly useful and candid conversations.

I sense there is a growing appetite for a new vision of inspection. Some of this resides among the Twitterati, some among academics such as Frank Coffield (his new book is worth a read), and some may also be felt at Ofsted HQ.

What is increasingly clear is that we need to think bigger and bolder about inspection.

Stephen Rollett is inspections and accountability specialist at the Association of School and College Leaders

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