The British detective novel has moved about as far from Auden's prescription as possible in recent years. The idyllic setting and genteel cast for the gentle art of murder have been replaced by the uncompromising realism of P D James, Ruth Rendell, Ian Rankin and Reginald Hill. None, however, has chipped away at prejudice quite so assiduously, or so courageously, as Minette Walters.
All Walters's novels question assumptions made by both her central characters and the reader, and much of the visceral thrill of solving their crime comes from discovering emotional and social verities as well as who dun it. The agent who does this is usually, although not always, a woman - the embodiment of professional, middle-class virtues - who refuses to judge others harshly. This is particularly appealing because Walters describes worlds that many of her middle-class readers would prefer to ignore, or condemn. In Acid Row, her eighth novel, the world is that of the paedophile.
A malicious health visitor on the verge of retirement deliberately lets slip the information that a paedophile is living on a nearby estate, nicknamed Acid Row. Melanie, a feckless but good-hearted single mother, correctly deduces the paedophile as Nicholas Franek, a music teacher who, as it happens, has been in prison with Melanie's black boyfriend, Jimmy. Panicked, the Franeks ask for a house visit from Sophie, a middle-class GP, whom they promptly kidnap. Nicholas is weak, but his Polish father is a violent rapist and murderer. Sophie becomes the emotional focus of the novel, fighting off Franek Sr and trying to enlist the support of his son. Meanwhile, Acid Row is building up for a riot, and the daughter of a single mother appears to have been abducted by a man who makes pornographic videos.
Anyone who reads the newspapers will see where the material for this story comes from. The ludicrous misallocation of space, the isolation of the elderly, the frustration of teenagers with nothing to do and nowhere to go, the struggle for decency and kindliness in adversity, all are well drawn. By weaving a suspenseful tale of courage and error around this grim territory, Walters addresses the ills of modern Britain as few literary novelists dare to do, afflicting the comfortable, if not comforting the afflicted.
That said, this world is altogether too soft-focus, and Ian Rankin has done it better. Walters has written a thriller, not a detective story. She makes clear her distaste both for mob action and for the reductive nature of the media, but even if you share this feeling, the reality is that people who live on council estates often behave violently towards suspected paedophiles because they have little choice, or voice, concerning their environment. The characterisation is dismayingly crude. Melanie is your archetypal tart with a heart of gold: she attacks a black boy, Wesley, when he calls her a "white bitch", by pointing out that the baby she is expecting will be black, too. That is as close as it gets to the poison of racism, a subject Walters has tackled with real subtlety and passion in The Shape of Snakes. The effort to be kind glosses over the real mess and horror of life on a sink estate.
Increasingly the novel, as it progresses, comes to resemble a screenplay, with the locations and viewpoints stated, rather than described. Walters is an intelligent and compassionate writer, but she is now producing too much too fast. Acid Row ends on a note of hope, with improvements in progress, a new network of pensioners, and Jimmy going straight. We all wish for that to be true, but this author was a better novelist when she wrote grim fairy tales, not stories from the land of Disney.
Amanda Craig's latest novel is In a Dark Wood (Fourth Estate, £6.99)