Marriage, the Supreme Court once wrote, is "the most important relation in life . . . having more to do with the morals and civilization of a people than any other institution." The case was Maynard v. Hill, and the question before the court was whether marriage was "more than a mere contract," a relation of such importance to the state that it could not be terminated simply by the consent of its parties. The answer was a resounding "Yes."

The year, however, was 1888 -- long before country-western singer Tammy Wynette spelled out that magic word, D-I-V-O-R-C-E. Maynard v. Hill stands today as little more than a monument to the bending of law to social change; its view of marriage as a "public ordination" deriving "from a source higher than any contract" has been erased by nearly every state legislature. With the advent of such procedures as "no-fault" divorce, husbands and wives may now effectively consent to end their marriages -- and do so in ever-increasing numbers. The remaining vestige of public interest in the event is a weary courtroom formality just slightly more strenuous than applying for an animal license.

This day in court is the lifeblood of D. T. Jones, low-rent lawyer, master of the $200 divorce, cheap labor on the assembly line of modern American justice. Although he was once a litigator of promise, his practice has evolved to the depressing specialty of representing wronged wives, exercised in the weekly courtroom purgatory of the "ditto list" -- the divorce court calendar, with its endless stream of Smith v. Smith, such v. such, so on v. so on, etc. v. etc.:

"D. T. appeared in court on behalf of five such women every week. He loved them all, and wished he could lavish them with riches, introduce them to swains, bathe them in oils, dress them in silks, shelter them from future sadness, all of which would be within the power of the thing he wished he was: Sir Jones. Knight Errant. Brave and stalwart. Champion of the Miswed. But instead of silks and oils . . . D.T. Jones would obtain for his clients the minimum legal judgment available to women of their station -- a Default Divorce. No alimony, no property settlement, no nothing usually. Only the silent disintegration of a vow, to be memorialized six months hence in a humdrum legal form, with appropriate boxes checked and blanks filled in and notices and warnings printed in boldface at the bottom, entirely unsuitable for framing."

There was, of course, a Jones v. Jones; and D. T.'s life is conducted in its shadow, his specialized practice an unconscious penance for his incompatibility with a doting, wealthy, beautiful wife. At age 46, battling the creep of age and the crush of creditors with nothing but regrets and a honed lawyer's instinct for the jugular, D. T. is stirred from despair by three new cases, one of them his thousandth divorce action. The result, inevitably, is an epiphany.

Author Stephen Greenleaf, a former lawyer whose "Tanner" novels rank among the best of current series mysteries, offers in "The Ditto List" an engaging variation of the hard-boiled California detective novel. As an entertainment, its pacing and comfortable characterizations overcome superficial flaws, particularly Greenleaf's tendency toward the cute, most painfully apparent when he waxes metaphorical ("Her voice acted on him like Clorox, bleaching his conscience"). But on inspection, "The Ditto List" is curiously hollow, at once obvious in its sympathies and reckless in its morality.

D. T.'s life-changing clients are conveniently worthy: a well-meaning but alcoholic hausfrau whose financier husband literally loves her then leaves her; a barefoot-and-pregnant teen queen whose redneck mate likes to use her as a punching bag; and a victim of multiple sclerosis abandoned to a life of poverty by her ex, a high-society gynecologist. A prospective knight errant could not ask for a fairer set of damsels; yet D. T.'s quests on their behalf are corrupt with conduct unbecoming that of chivalry, let alone that of lawyering.

What is particularly troublesome is that we are meant to admire (or at least identify with) Jones' efforts, not to mention his lowbrow charm -- compulsive gambling, two-fisted drinking, the cynical, self-pitying commentary that we have come to expect of the hard-boiled genre. But in a novel that, by definition, is about responsibility -- of husbands and wives, as well as of lawyers -- these antics soon ring false. We are told constantly that D. T. Jones hates himself for what he does, yet the real message here is that the end justifies the means. No amount of humor and suspense can obscure this book's ironic confirmation of Maynard v. Hill at least in the world of "The Ditto List," the devaluation of the institution of marriage has indeed affected our morals and our civilization.