When the voice of a boy soprano begins to break, there are a number of ways the situation can go. He must manage the change, whether he does so well or badly. He should face the possibility of a public disaster in the middle of a performance. He can work cautiously through the transition and discover that he has, or does not have, a good tenor or baritone or bass. Or he can give up singing altogether.
This analogy for the situation in which J.K.Rowling finds herself is not without its flaws. For one thing, boy sopranos have no choice in the matter. But the management of a major shift in your voice - its range, its pitch, its target audience - is a tricky and complex thing whether you have chosen it or not, for all new registers require new techniques. And if you are a writer whose books for children have earned you fame beyond the dreams of narcissism and wealth beyond the dreams of avarice, and who then decides to shift into an ''adult'' register, you have to manage that shift in the fierce and blinding spotlight of public attention.
Early reviews of this novel have concentrated on its material, many expressing disquiet that Rowling should have traded in the matter of Potter for a story involving drug addiction, self-mutilation, rape and suicide. These people seem to have forgotten that one of the main characters in the Potter books is the embodiment of evil itself. It isn't very difficult to write about bad things; the real difficulty for a writer is to manage the changes in the storytelling voice.
Warm, familiar, easy and clear, Rowling's voice in the Potter books is like an extra character, using the same kind of language that the characters and their readers use, and making the same kinds of observations about them that they make about each other. But at its most successful, the narrative voice of The Casual Vacancy is quite different. Detached, mature and sophisticated, given to abstraction and reflection, this is the traditional omniscient narrator of realist fiction. The new voice wavers and wobbles sometimes, especially in the early chapters, where Rowling reverts from time to time to the treble regions of her Potter mode. This isn't necessarily a bad thing, as it's easy to forget how funny she can be: ''Krystal's slow passage up the school had resembled the passage of a goat through the body of a boa constrictor, being highly visible and uncomfortable for both parties concerned.''
But after 100 pages or so the new voice is settled, steady and full of confidence; one character, we are told, ''had a habit of making sweeping judgments based on first impressions, on single actions. He never seemed to grasp the immense mutability of human nature, nor to appreciate that behind every nondescript face lay a wild and unique hinterland like his own''.
The casual vacancy of the title is a position on the Pagford parish council that goes up for grabs when a much-loved local dynamo, the allegorically named Barry Fairbrother, drops dead in the golf club carpark. The competition over the vacancy is one of the several things that give this story its strong forward movement, as is the fight over whether or not Pagford will retain responsibility for ''the Fields'', the problem-riddled council housing estate on its outskirts, or whether they will hand it back to the bigger district council.
The structure of village life in Pagford is a faint, distorted and rather pathetic echo of feudal England, from the richest family in the biggest house down to the desperate inhabitants of the Fields, who live in the contemporary equivalent of mediaeval peasant squalor. Rowling is nothing if not clear about where her political sympathies lie, and her satirical treatment of middle-class, English-village gentility is unrelenting. Nor, however, does she shrink from describing the sheer physical awfulness of life in the Fields: ''Kay noticed a used condom glistening in the grass beside her feet, like the gossamer cocoon of some huge grub.''
Rowling's highly cinematic imagination provides any number of set pieces over which any director might salivate, dreaming of the screen. There's the fastidious female Sikh doctor being obliged to examine the skinfold rash under the vast belly of the repulsive Howard; the three vulnerable teenagers bonding in the kitchen during the saturnalia that is Howard's birthday party; the terrible 10 minutes along the riverbank, during which the characters converge and the plot plunges downward into tragedy.
As with the Potter books, the carefully structured plot is enacted by a cast of memorable and highly individuated characters, seen in sharp focus. Rowling is particularly good with adolescents, of whom there are several: their alliances, their enmities, their insecurities and the often strange logic of their thinking are all treated with an insight and empathy that stop well short of optimism, much less sentimentality. The adult characters are drawn with broader strokes; most of them are somewhere between fairly awful and completely frightful. The only wholly lovable adult in this novel is Barry Fairbrother, who has been dead since page 3. And despite its incidental humour and its selective tenderness for a few of its characters, the novel's ending has been described, with justice, as ''howlingly bleak''.
But some of the public fretting about keeping this book away from children seems unnecessary. Children are gifted self-censors and most will not persevere with a book beyond their reach; any child still interested enough to keep reading after 10 pages is probably ready to do so. Besides, the central message of this novel is that we are indeed our brothers' keepers: we should take better care of each other. And that, surely, is a lesson any parents would be glad to have their children learn.