So, if I’m faced with an accusation against a member of my staff, I instinctively respond to my single defining principle. I know that, by itself, it’s no answer to how schools should be dealing with potentially false accusations against staff (the Issue, Friday magazine, February 20), but it is where I always begin.

In this school, no matter who you are - student, staff, parent or governor - it is OK to tell. You could be a kid who says you’re worried about something a member of staff has allegedly done to you, a teacher who owns up to having got it completely wrong, or a child courageous enough to tell of another child’s lies.

I begin by listening and taking notes. If I’m sensible, I let my hand be held by a senior pastoral leader who knows my school and my pupils better than anyone; she has a clear-up rate the Met would die for. I then collect evidence. At this stage it’s about feeling the weight, the potency, of the accusation. I never decide without taking time to reflect. And I’m never frightened to phone the Secondary Heads Association’s hotline to tell them what I’m intending - but not to ask what to do. I’m the head. It’s my call.

In my experience, allegations against staff fall into at least three categories. The first group are the staff who, on the day, just lose it.

Almost always massively provoked, they’ve grabbed hold of a child, or sworn. They’re easy to deal with because they know they got it wrong. Then there’s the worryingly growing group of staff who are the victims of malicious accusations. And then there are the others, those teachers whose behaviour and attitudes make your instincts scream that something really is wrong.

When we employ anyone new we always ask for enhanced disclosure from the Criminal Records Bureau. How else can we make balanced decisions that put our children first and are fair to the staff, teaching and non-teaching? And would I steer clear of anyone who came up with a history of allegations, or a profile gleaned through references that made me question for a moment their suitability? Too right I would.

But I hope that if the references, the vibes and the lesson observation were right, that we would have the courage to appoint someone who had been charged and exonerated, although it would be a call I would have to share with my governors first. I don’t know how common it is for falsely accused teachers to be discriminated against, and I’ve never been phoned by another head over the alleged abusive behaviour of a member of staff. But I do know that a growing number of children will lie, both as a reflex and as a strategy to deflect guilt. That’s why proper recording procedures are essential.

It’s the same with abusive staff. Any behaviour that is suspect has to be challenged and recorded before it becomes a threat. Too often it is my guess that headteachers inherit staff whose profiles bear no substantial evidence of their ingrained behaviour. So maybe it’s our fault that this tiny minority remain in our profession when they should not be allowed to work with children at all.

As for those unlucky enough to be falsely accused, we can only hope that our schools and LEAs are prepared to treat each case individually on merit and not simply as an unnecessary category of risk.

The writer, who is the head of a secondary in the west of England, wants to remain anonymous