This week, my progeny — two boys, aged 11 and eight — were at the centre of a dispute that will give them an abiding memory of the law of the land. We have, of course, been blessed with extraordinary weather, and so, one afternoon when the boys were back from school and I found myself ahead of my work, we decided to go for a walk alongside the nearby River Coln.

This is a beautiful river that meanders lazily through the Coln valley, in the southern Cotswolds. We have lived in a village in the area for some five and a half years, and though currently in the midst of a move to Cornwall, have many fond memories of this part of the world. Each summer, we and other families would wander down to a field that abuts the River Coln, to picnic, paddle and let our children catch crayfish. The field is owned by a village resident, whose country pile is also adjacent to the field. Ever since anyone could remember, this kind lady allowed villagers to roam across the field and paddle in the river. Her largesse was much admired and appreciated.

But at the beginning of the year, her groundsman began marking out the river bank. Before anyone knew what had happened, still less why, a fence had been built all along the river, complete with barbed wire. It was an eyesore, and provoked letters to the local paper. I asked the groundsman why the fence had been built. "Because of the cows," he said. Apparently, the fence was required to stop the herd of 10 or so cows that use the field for a few months of the year from depressing the river banks and, potentially, altering the flow of the River Coln.

But this is not the full story. This week, on our walk, my boys and I reached a bend in the river where there is a ford. It never used to be fenced off, and, indeed, was formerly the prime paddling spot. It was boiling hot, and the boys asked if they could go in the river. I checked that the cattle, in calf, were nowhere near us, and said "Go on, then, be quick." Yes, shocking but true, I hereby admit that allowed my children to paddle in the River Coln.

I compounded this crime by our choice of route home. We eschewed the designated footpath for by then it was in shade, opting instead for another one that appears to have been created recently (by whom, I do not know), and which bisects the field. Midway along this, as the boys were happily flying paper aeroplanes, I been aware of the groundsman running towards me. He was some 50, perhaps 75, yards away, but was sprinting as fast as he could. I could see his eyes bulging out of their sockets, but I was so stunned that I assumed he must be heading for something behind me — perhaps a cow had decided to charge us. I looked round, but there was nothing, save for the terrified faces of my children. I looked back to see the groundsman complete his sprint and stop a foot away from me.

He was shaking and his fists were clenched. He proceeded to scream at me, his mouth frothing rather unpleasantly as he did so. "Keep to the path!" he said, again and again, at the top of his voice. He looked deranged, and I am sure that if I had said anything within the first seconds of his arrival, he would have hit me. I should point out that, by his own account, he is a former boxer (and has the sideways nose to prove it). In the interests of fairness, I should also make clear that he knows that I box, for we have, in what are now clearly halcyon days, discussed the manly art of self-defence.

His extraordinary tirade continued, to the terror of my boys, who stood, petrified, behind me. Eventually, he stopped. I suggested that he calm down. He started shouting again. I said I would talk to his employer about this incident. Off he went again. And then, I snapped. I got fed up with this ludicrously disproportionate response to our wrong of petty trespass, and I felt angry that he felt he had the right to place my boys and I in fear. So I shouted back, louder than him. Blows were not exchanged, but I did offer to meet him in a boxing ring. That offer still stands, but the fortunately the conflagration subsided, and me and the boys were able to continue our journey home.

I rang the lady whose largesse appears to have disappeared, and asked if she condoned her employee sprinting with a demented glint in his eye to rage at a man and his two children, whose crimes were, admittedly, ones of trespass, but whose lasting import was zero. "He was looking after my interests," she replied. I said I was astonished, retold the events of the afternoon, and asked again whether she could seriously condone her henchman’s behaviour. "I think he had just cause," she said.

My boys and I have discussed the matter. The land is hers, and, for whatever reason, the good old days of paddling, picnicking and catching crayfish are gone. If anyone strays from the path to fly a paper aeroplane, they commit a further trespass. This, I said, is the law, and we infringe it at our peril. "But Dad," said my younger son, "I was scared when that man ran at us and started shouting. Does the law say he can do that?" No, it does not, I said, for it is true — a landowner, and her henchman, must act reasonably and not commit assaults in the protection of their domain. Then I remembered him running at us, and I felt outraged again, and, as I type this, I feel like having that boxing match. But we civilised lawyers do not over-react in such ludicrously disproportionate fashion, least of all to provocation by ignorant, small-minded bullies, who place our children in fear. Or do we?

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