Back in the Land of the Crazies : GOING LOCAL.<i> By Jamie Harrison (Hyperion: $21.95, 323 pp.)</i>

A young and idealistic Chicago alderman once told me he was blessed with a touch of larceny in his heart; blessed, because it enabled him to sniff out the larcenous intentions of his fellow aldermen.

Some such communal empathy makes Jules Clement a perfectly qualified sheriff for the rowdy town of Blue Deer, Mont. His college days were heavily into controlled substances and he still drinks far more than is good for his liver. His love life is a mosaic of moments, some of which he remembers the next morning. One way and another he is as free a spirit as ever an honest sheriff can be, with a high leavening of compassion and a prevailing rage at injustice.

He is an original and engrossing creation, making another appearance in “Going Local,” Jamie Harrison’s second novel (following “The Edge of the Crazies”) about Clement and Blue Deer, which may or may not resemble Clark City, where until recently the author was a newspaper editor. (Harrison is the daughter of the excellent novelist-screenwriter Jim Harrison, and powerful genes would seem to have been at work; she is a wondrous writer.)

Montana is itself a principal character in “Going Local,” evoked by the author with a kind of sardonic reverence:

“The land around Blue Deer was achingly beautiful, the landscape as a map of the soul, with long cold sadnesses and sudden, verdant, short-lived frenzies of happiness and new life. . . . It was only at certain times . . . that Jules’ affection for the landscape turned bitter and made him want to lash out at all the idiotic, self-justifying romanticism aimed at packaging the state for investors and tourists.”

In “Going Local,” a man and his new lady-love are murdered during a camping trip--run over by a truck and then dumped, tent and all, into a reservoir. (Harrison is among her gifts a very inventive plotter.) The man, a lawyer, has been helping his ex-wife, Blue Deer’s salty grande dame, assemble the acreage for a huge, controversial multipurpose development in the local mountains, the Crazies.

The grande dame’s new husband and partner in the venture is a British director, part of the artist and writer invasion of the Big Sky country. Another of the partners is one of Clement’s boyhood rival/friends, who has also come home again after a rich career as a lobbyist, fetching with him a spirited woman Clement quickly gets to know well.

Town life goes on, including the local rodeo, during which the grande dame is fatally injured when her horse collapses and dies, crushing her. (The horse, in another of Harrison’s darkly felicitous plottings, had been poisoned.)

Clement tries to confront the expanding mystery as he juggles the various burdens of office. (The daily police log, as printed in the local paper, was a delicious invention in the first novel and returns with great effect here.)

Harrison’s story is daringly structured in the sense that its incidental music is so good, its capture of place, characters and relationships so detailed and persuasive, that the tightening plot seems almost incidental. It isn’t, of course. The denouement is dramatic and ironic, not so much a surprise as a confirmation of suspicions with all the damning details in place.

Part of Clement’s appeal is that he is a working sheriff, not a brilliant, intuitive sleuth, though he might well agree with Sherlock Holmes’ dictum that when all other possibilities have been eliminated, what remains must be the truth. Sure enough, after Clement’s chases, beddings, fights, hangovers and detours into cul-de-sacs, the denouement is at hand, painful and inevitable.

What seems characteristic of the best present crime-writing is surpassingly true of Jamie Harrison: She is creating entertainment and diversion but she is also writing social history as accurate in its essences as a road map and generating a most admirable work of literature with what should be a long shelf-life.