I'VE PLAYED a big part in the Walk-On-By society, and I'll miss it when it's gone. Jack Straw can do what he likes, but I have no wish to meddle in the affairs of troubled teens going about their normal criminal mischief. In fact I usually go out of my way to avoid young people of vandalising age, roughly eight to 15. I don't like them, and they don't like me. Oh, they can be friendly enough when they want you to buy them a couple of bottles of Hooch from the off-licence, but they soon forget such kindnesses.

Despite my best efforts, poor route-planning has occasionally led me directly into the path of young people. Only last half-term I found myself bearing down on a pack of 10-year-olds who were coming from the shops. As they approached, the smallest one held his ice cream up to me and said, "Would you like some?" And then: "Go on. You deserve it." The rest of them laughed. What could I do? I Walked On By. The world-weary expression of benign exasperation I wore for the rest of the day was little more than a brave front. I was, for reasons I still do not fully understand, humiliated.

Although I avoid young people, that doesn't mean I'm not interested in grassing them up. On the contrary, I get a real kick out of it. My specialty is curtain twitching. I can happily spend the evening peering between gently parted blinds, engaging in my own personal neighbourhood watch. I immediately report anything suspicious to my wife, and encourage her to ring the police. "Two youths on the roof of the Stay `n' Play!" I shout. The rest is up to her.

Now that I have children of my own, I find it increasingly hard to avoid young people, as I am forced to frequent the very playgrounds, parks and swimming pools these ruffians call their own. On these occasions I am disturbed to find that my mere grown-up presence does not in itself constitute a deterrent to petty crime. I try to employ a scowl of malignant disapproval, but they just carry on setting fire to the slide. They could at least have the decency to wait until I'm gone.

If we are to carry on visiting playgrounds, I am going to have to teach the older child to swear properly. It's hard enough for me to maintain my Bad Lieutenant air of menace while pushing a baby in a swing, without the other one running around shouting things like "I'm quite cross!" at his fellow children. It's strange that he's never picked up any swearing, given his mother's great affection for the F-word's present participle, which makes her every phone call sound like a mafia wire-tap recording. The other day at the pool he got extremely angry with me for trying to coax him away from the ladder, and he called me the worst thing he could think of: willy-man. I'm no child development expert, but the boy is four-and-a-half, and I think he should be calling me an arsehole by now. I must ask about him at school.