BOOK REVIEW : A Fine Round of the Remarkable Rumpole : RUMPOLE A LA CARTE <i> by John Mortimer</i> . Viking, $18.95, 246 pages

Rumpole, that amply built, slightly disheveled, classically educated, sadly underemployed barrister, is back in a new set of stories, “Rumpole a la Carte,” and eager to take your case between appearances on PBS. Rumpole can’t afford to be fussy. The clients who come his way tend to be desperate, impecunious, and unjustly accused; the glamorous, the wealthy and the guilty go elsewhere, to those with Savile Row suits, old school ties, and a more flexible approach to the majesty of English law. Rumpole, as he would be the first to admit, is something of an anachronism.

Though Horace Rumpole almost invariably appears for the defense, one of the most diverting stories in this winsome collection casts him in the uncongenial role of prosecutor. In order to appear on the wrong side, he must reject virtually all his most cherished principles. And, as he says, “It seems to me that errant and misguided humanity has enough on its plate without running the daily risk of being driven, cajoled or hoodwinked into the nick (prison) by Rumpole in full flood, armed with an unparalleled knowledge of bloodstains and a remarkable talent for getting a jury to see things his way, as everyone--except a nun in a Trappist order and the Home Secretary--now knows the prison system is bursting at the seams and it would be out of the question for even more captives to arrive at the gates thanks to my forensic skills.” (Modesty is not one of his virtues, though irony is.)

In this exceptional tale, he’s retained to prosecute one Christopher Jago, accused of murder but subsequently released for lack of evidence. Rumpole has been engaged by the father of the victim, a young woman bludgeoned to death in an empty mews house. In the course of his investigations, Rumpole uncovers evidence that results in an acquittal for the accused; a first in his own career and quite possibly a first for the whole judicial system.

While Rumpole’s cases may seem less than world-shaking, they offer author John Mortimer a marvelous opportunity to comment upon the vagaries of British law, the eccentricities of his colleagues in chambers and the sad erosion of traditional British values. In “Rumpole and the Summer of Discontent,” an incident in a restaurant involving a live mouse and a philandering associate becomes a thoughtful and witty essay on the proposal to modernize the archaic distinctions separating barristers from solicitors. “Now, many things may be said of the British legal system, but it seems odd to me that it should be run as a supermarket, round which you trundle a wire wheelbarrow and pick up a frozen packet of the burden of proof or a jumbo-sized prison sentence, with 10 p(ence) off for good behavior.” Of course, if solicitors were to be allowed to plead before the bench, “the Old Bailey hack, skilled in the art of advocacy, which is his daily bread, would be in danger of extinction.” Even more than Rumpole himself, his admirers would hate to see that happen.

“Rumpole and the Right to Silence” deals with that precious principle, “the golden thread that runs though British justice”: the guarantee that a suspect may decline to incriminate himself. This imperiled freedom, equally respected in America as the Fifth Amendment, is apparently currently under attack in England. “Must we go back to Runnymede every so often to get another Magna Carta and cut off King Charles’ head at regular intervals, to ensure our constitutional rights?” runs the commentary here. If the case that inspires these meditations seems slight, the issue is a crucial one, not diminished in the least by the author’s tart wit and amusing digressions. They’d be the last to admit it about themselves, but Mortimer and Rumpole deserve to be taken seriously.

Next: Carolyn See reviews “The Little Karoo” by Pauline Smith (St. Martin’s Press).