OUTLAWS By George V. Higgins Henry Holt. 360 pp. $17.95

GEORGE V. HIGGINS dislikes being called a crime writer, feeling the label is limiting and that his subject is the human comedy (or perhaps what Aldous Huxley once called the human vomedy) as displayed in and around Boston. Well, Higgins isn't Agatha Christie or P.D. James, that's for sure, but his chief characters are violent, commercial or political crooks and their legal hunters. For me he's a crime writer who is also a fine novelist. Nothing contradictory about that. He is also sometimes, as here, a novelist of a highly moralistic kind.

In Outlaws the criminals are half-a-dozen young men and women, well educated, some brilliantly intelligent, their parents well-to-do professional people. They first rob armored cars, eventually move on to multiple murder. The Bolivian Contingent, as they call themselves, are rebels with two causes, stealing enough money to live comfortably and acting as rebels against organized society. Over a period of seven years they are traced, and four of them brought to trial, by Lt. John D. Richards, a detective in the Massachusetts State Police, and terrier-like Assistant Attorney General Terry Gleason.

Does this sound like a fairly orthodox tale of cops and robbers? That isn't so, and the difference is principally in the way the story is told. Higgins is a master of indirection; few of his characters say what they really mean or think, and he deliberately avoids the climactic scenes of violence in which lesser writers indulge themselves. A passage early on shows the technique. The gang is known to be on a boat in a marina, and the police intend to send an apparently innocent houseboat full of well-armed combat veterans alongside to arrest them. A young woman police officer is deputed to be lounging on top of the houseboat in a bikini, Richards tells her the dangers of the assignment in graphic detail, and we expect the raid on the boat to follow. But that is not Higgins' way. The scene has been devised to tell us a little more about the gang, Richards and the woman cop, not as a prelude to violence. The next we see of the Bolivian Contingent they are facing trial.

The hundred pages given to the trial are among the finest Higgins has written. He shows us the weakness of the prosecution case even though there is no doubt of the defendants' guilt -- most of the evidence is hearsay, and their one stool pigeon is too frightened to be put on the stand. He shirks none of the complications, the legal shifts and stratagems. One defense lawyer with a hopeless client ("Che taught that love is the only motivation of the true revolutionary") gathers an immense amount of useless evidence so that he can claim, Gleason tells Richards, "that Bigelow was diligent, hard-working, that he really prepared his case." We see the judge doing all he can to help the prosecution while keeping strictly within legal limits, and the deliberate use of an insanity plea by counsel for Sam Tibbetts, the evil genius of the Contingent, and the successful use of it by Tibbetts himself and his counsel John Morrissey. When the jury reaches its verdict, the judge tells Gleason: "You rode a lame horse a good race, and you won most of it."

THE END of the trial is not the book's climax. There are surprises to come, some of them carefully concealed, and it would be wrong to name them. But the general drift is that we are all outlaws, and that officialdom does by stealth what the Bolivian Contingent did openly. There is a concern to show us also that modern life has no room for knights in shining armor. Gleason has prosecuted the young drop-outs with passionate determination, but within a year or two he has turned defense lawyer, and is getting rich pickings from the crooked clients he detests. Tibbetts meets his fate offstage, like most victims of violence in Higgins' novels, but does so through the agency of impeccably respectable members of society.

There is something mechanical about the clatter of ironies with which the novel ends, and points are pressed a little too hard at times. But if Outlaws lacks the perfect shape and pacing of Cogan's Trade and The Judgment of Deke Hunter, it confirms Higgins' astonishing ear for speech and his ability to build a novel almost entirely out of two-voiced conversations, with action described briefly and deadpan, or told by one character to another. Higgins can be erratic and long-winded, his characters can seem simply gabby (though not in Outlaws), and there are times when one feels doubtful that he knows just what he is doing. Yet at his best he can achieve effects outside the scope of any other living novelist. There are plenty of good straightforward fictioneers around: but George V. Higgins is a writer of genius.

Julian Symons' books include a new edition of "Bloody Murder," his history of crime fiction and many mystery novels. A collection of his essays will be published this fall.