Schools, it is said, are based on trust: trust between teachers and pupils, between teachers and parents, between teachers and senior leaders and between teachers and government. Although, perhaps, the last not so much in recent times.

“At the most basic level, the need to trust implies one fundamental fact: you’re vulnerable,” says psychologist David DeSteno, director of Northeastern University’s Social Emotions Lab, in his book The Truth About Trust: How It Determines Success in Life, Love, Learning, and More. “The ability to satisfy your needs or obtain the outcomes you desire is not entirely under your control.”

And it is this vulnerability that lies at the heart of the contentious adoption in education of bodycams, the wearable cameras that record events. There is no doubt that in some schools teachers feel very vulnerable, with both the ATL and Unison unions reporting increasing problems of violence. Bodycams can record the incident and provide what is often much-needed proof.

They also have a preventative effect. In the US, they have reduced crimes against police officers to such an extent that they are also being used in the classroom.

Now, two British schools are planning to use them to record incidents of bad behaviour.

But how do teachers feel about them? A TES survey found that some 37 per cent are prepared to wear such a device; 66 per cent said they would feel safer if there were a camera in the classroom.

But one big concern lies with the fear that the tables would be turned on them, with 19 per cent worried that bodycams would be used by management to spy on them. So much for trust between teachers and school leaders, then.

And once you start to pick at it, what you have in schools is more a veneer of trust rather than an underlying foundation. It could be argued that if government and parents really trusted schools, there would be no need for Ofsted. If heads really trusted teachers, there would be no need for observations and performance management. And if teachers really trusted the children, there would be no need for a behaviour policy.

In fact, the education system is already engineered to create reliable mechanisms to replace trust; bodycams are not a big departure from those. What they do suffer from, however, is the sinister associations with 1984 and Big Brother, something that does not affect classroom CPD video, which is seen as non-threatening. It may not look like surveillance, but it is.

But are bodycams really necessary? Is behaviour truly so bad? The unions, of course, have an interest in talking up the problems. Good and well-enforced behaviour policies should be enough in most places. But for those where teachers and students do feel threatened, shouldn’t they be given the security they need?

For others, it is a step too far. One respondent to the survey said: “Our relationship with students is the single most important factor in teaching, why would we want to start that relationship from a position of mistrust?”

Children, however, soon learn to live with cameras recording their every move without feeling an erosion of trust, as the Educating… series testifies. If a bodycam (roughly £100) provides a safer environment and cuts time wasted on complaints to create more time for learning, then it’s a good investment.

Until the Dunblane school massacre in 1996, we trusted the public to wander freely into schools. The world has changed even more since then. We must change with it.

@AnnMroz