PRESUMED INNOCENT by Scott Turow (Farrar, Straus & Giroux: $18.95; 431 pp.)

“Presumed Innocent” plays to all levels. It is murder-mystery intrigue at its best, woven into a factually interesting and accurate web of courtroom preparation and drama. “Having a jury out is the closest thing in life to suspended animation, even the simplest tasks are beyond attention.” So true.

The psyches of the killer and the prosecutor alike are explored with Dostoevsky-like insight. “I do not want this mad act to have no decent consequence,” the prosecutor cries. The author’s unique first-person prose style flows like fine oratory.

Rusty Sabich, the son of a war- ravaged Slavic immigrant father, is the first assistant prosecuting attorney in a large, hypothetical, somewhat corrupt Midwestern city. “My experience as a prosecuting attorney was that people weren’t just a little corrupt. It’s a progressive disease.” The courtroom scenes are vividly Chicago, where the author, as assistant U.S. attorney, has personally prosecuted courtroom corruption.

Sabich is in early middle age, behind him “seventeen years of faithful marriage with a wandering impulse suppressed for the sake of tranquil domestic life.” The suppression is released by a Machiavellian co-prosecutor, Carolyn. After they co-tried a number of cases, he became obsessed with this “conquistadora of wayward passion.” “My approach to her was prayerful, on my knees, perfect mad wild moments, passion as pure as music.”

Unfortunately, Carolyn cruelly dumps poor Sabich on her way to more important conquests. And Sabich’s unrelenting obsession causes him to confess to his wife, “a mad egoistic instant that only made the suffering worse.”

Shortly before Sabich’s boss’s re-election bid, Carolyn is found murdered in a sexually bizarre fashion. Sabich is appointed to conduct the investigation and does it in what is viewed as a slipshod manner. This raises suspicions. His boss loses, and the new prosecuting attorney pieces together evidence that causes Sabich to be indicted. He becomes a Midwestern Dreyfus.

The author blends the unusual insight of prosecutor, as defendant, helping his attorney prepare the defense. He now sees the process through another prism, “everything the prosecution discovers which favors the defense must be turned over.” A constitutional concept hated by Sabich the prosecutor, but finally understood and appreciated by Sabich the defendant. “I’m innocent!” Sabich implores. His “attorney has a look of deep, if practiced, sadness. He has heard these ardent proclamations of innocence too many times before to be moved.”

As his trial approaches, the accused prosecutor reflects on the realities of prison life. A reflection nightmarishly real, and, unfortunately, vividly accurate. “The bars are heavy iron slats, painted flat black, and behind them--now it strikes you--they’re all so much the same. They are the ones who always wore their deficits like scars, headed to prison almost as certainly as a skyward-shot arrow plunges back to earth.”

As the lawyers debate Sabich’s fate, he ruminates about his murdered lover. “What forge of cruelty produced her? The synapses and receptors were in working order on her heart and feelings--but they were overloaded by the need to give solace to herself.” The progeny of abuse, she abused in her turn. Sabich reflects: “Every prosecutor learns that we live closer than we want to believe to real evil-doing.” Sabich’s wife, a woman “capable of the most intricate levels of complex thought,” stands stalwartly by her husband throughout the trial. Things are better now between the husband and the wife. Passion and feelings have been rediscovered. But there are no happy endings. The tragedy takes unimaginable turns to the very end.

The insight, clarity and realism of the trial proceedings combine with an emotional involvement the author creates by making us care so much about the characters. This combination brings the reader as close to the actual trial experience as would ever be possible without suffering the “gut-wrenching sleepless nights and red-eyed mornings.”

Other than in one of my cases, I cannot remember ever being so concerned about the outcome of a trial.