Who is the best novelist sitting in Parliament today? In the Lords, the deeper talent-pool of life peers means that the question might have a point. Melvyn Bragg, PD James and Ruth Rendell could each stake a claim. In the Commons, however, we come back down to earth - and a scattering of MPs who have perpetrated corny potboilers or youthful indiscretions. Chris Mullin, now the scourge of Barclays but once a fiery backbencher with a creditable line in political thrillers, should probably lead this plodding field.
Now he has a competitor with ambitions for a long-haul literary career. Is Ann Widdecombe's first, unremittingly bleak family saga as dismal as some readers might assume? Not exactly; or rather, its routine flaws come within a surprising, even perplexing, frame.
Miss Widdecombe writes a stodgy meat-and-potatoes prose, and confines her gaze to a narrow segment of the middle classes. She doesn't do sex, she goes in for fortitude, and she heartily approves of nuns. Hot news, eh?
But consider what actually happens. Accountant Mark and his wife Claire have their comfy life dragged through the mangle when their four-year-old, Jeremy, runs in front of a speeding car. Paralysed, with severe brain-damage, the boy becomes their Calvary. Time and again, their marriage almost breaks under the strain. In clumsy flirtations and fantasies, Mark dreams of "playing away" with other women. Poor Claire simply goes on the odd shopping binge.
Yet their burdens have to do with feelings, not finance. This is the lamest cop-out. The wealth of Claire's scrap-dealing Yorkshire dad means that the couple never face the sheer material desperation that 99 per cent of such parents will confront. To that extent, this book remains, for all its lavish misery, a Tory fairy story.
Not entirely, though. What's truly weird is not its easily bought stoic moral, but the point of view. We see this grim tale through Mark's eyes: an agnostic with a Jewish mother, who distrusts his wife's social pretensions and even keeps his distance from her vehement right-wing politics - "passionately, and perhaps, intolerantly, Conservative". Claire emerges as an uptight snob who refuses to send Jeremy to a council-run centre alongside kids called Kylie or Dean; Mark as the average sensual, but reasonable, man. In short, this novel's central consciousness - masculine, liberal, sceptical - is not what the name on the cover might lead you to expect.
An ambiguous sub-plot revolves around Claire's high-flying MP sister, Sally, and her bid to introduce a bill legalising euthanasia. Even here, various twists ensure that there's precious little right-to-life tub-thumping in the text. As for any other clear political message - well, given the frequency with which high-speed vehicles smash up young lives in The Clematis Tree, it might as well be calling for a total ban on the internal combustion engine.
Jeremy dies in a painless accident, leaving Mark - before a last-gasp change of heart - to dread the future of his moribund marriage as "empty years of duty and pretence". Yet his son's short life has allowed others to show love and loyalty; just like the stunted tree in someone's garden, around which a glorious climber blooms. Hence that horticulturally unfeasible title.
Passive and powerless himself, Jeremy enables others to do good. Wordsworth has a wonderful poem on this very subject, in which abject need permits luckier souls to show "their kindred with a world where want and sorrow are". Entitled "The Old Cumberland Beggar", it argues that mendicant strangers at our gate should prompt a "needed kindness". This teaching chimes perfectly with the theme and tone of this compassionate novel. It can be beautiful "to live for others passively", as a trigger for their altruism, comments one of Mark's not-quite-girlfriends. It hardly needs to be said that all this flatly contradicts the spiteful claptrap against asylum seekers we often hear from the woman who holds the post of Shadow Home Secretary.