Female gang violence is by no means a new product. As a schoolgirl in the Nineties I would be wary of taking certain bus routes home, for fear of muggings or random attacks at the hands of hard, vicious girl-gangs. These girls were almost butch, macho in their posturing and language, callous in their brutality and ugly as sin. Scared as you were, you could not help feeling a little sympathy for these raw, angry mangirls, already disappointed with the world. They'd been dealt the worst hands - big bones, mean features - and they were wild for retribution.

So it came asa shock last week to see the first pictures of Chelsea O'Mahoney, the girl found guilty with three others of the manslaughter of bar manager David Morley.

While Chelsea, now 16 but 14 at the time of the attack, is unlikely to have modelling scouts beating a path to her door, she is a looker, her bright blue eyes betraying intelligence and a sense of humour, rather than any psychopathic inner torment.

The brutish girls of my youth had to concede sexual favours to gain any kind of acceptance, but Chelsea's face makes me doubt she was one of those. She is too pretty. She had choices.

In my experience, the prettier girls were also expected to give, but only the alpha males on the estate need apply. The council estate stunners did not have to win anyone's approval, did not have to go that extra mile to join the gang.

If you are pretty, doors open. If you are ugly, you are going to have to graft for any of life's little perks. So from the moment I heard of the Morley case, I assumed Chelsea would be as rough as they come.

Zadie Smith writes brilliantly about the way that looks can forecast lives in On Beauty, her latest novel. Squat and undesired, Zora says of the statuesque Victoria: "She hasn't quite worked out what to do with her beauty." Zora intends this as a put-down, implying that Victoria is too gauche to recognise her own pulchritude, let alone harness it. But her catty observation betrays the greater truth: that Victoria has a choice. It will be for her to manipulate her own future, rather than have it handed to her, prepacked and labelled.

Chelsea had that choice. Even given her dysfunctional background and hopeless parenting, in a vicious world, her looks gave her a head start. Far from being another of society's rejects, this wretched girl conformed to another teenage stereotype, the Good Laugh.

The Good Laugh is a different type, not confined to the mean streets. Anyone from any class, low on self-esteem, can be typified as such by friends and by culture. He or she will do anything to gain attention and acceptance and, more often than not, this entails making peers laugh, usually at their own expense.

It is plausible to conceive of Chelsea going along with the gang, going that little bit further to secure her status as a Good Laugh, one of the boys. The tragedy is that Chelsea would have believed, or convinced herself, that her peers' pastime of videoing their assaults on random victims was an amusement.

But the "slapping" of David Morley turned out anything but happily for her. She has several years in custody to reflect upon that. Yet she will be no older than 21 when she is released and will still have bright blue eyes and a pleasing face. She may yet, therefore, have choices that others on her prison wing were denied at birth.

Helen Walsh is the author of 'Brass', a gritty novel about a tough upbringing in Liverpool