Lord Knows : SILENT WITNESS.<i> By Richard North Patterson</i> .<i> Alfred A. Knopf: 494 pp., $25.95</i>

What distinguishes Richard North Patterson from other best-selling authors of legal thrillers is that you become so emotionally involved with his characters that you can’t bring yourself to give his books away. I routinely pass on my Scott Turows and John Grishams, but Patterson’s last three books are lined up neatly on a shelf where his latest, the enthralling “Silent Witness,” will soon join them.

The novel begins with Tony Lord, a San Francisco defense attorney, winning a high-profile murder trial. So his socialite client admitted that she killed her millionaire husband; Tony argued that it was “battered wife syndrome” and, as he later assures his skeptical wife, he’s never had a client walk on a murder charge and go out and kill again.

Tony appears to have everything: a flexible conscience, a gorgeous Oscar-winning singer-actress wife, an expensive house in Pacific Heights and a national reputation. “At 45, Tony retained the all-American look that seemed to invite confidence: blond hair cut to a moderate length, a youngish face that was strong but not threatening, candid blue eyes and a jury persona to match. He was never arrogant, never overused his gift for irony, never took that obvious pleasure in his own skill that might cause a juror to dislike him.”

Of course, being the hero of a suspense novel, Tony has a dark secret, which finally catches up with him after his big victory when he receives a long-distance call for help from Sue Robb--a woman who was once more than a close friend. Her husband, Sam Robb, once Tony’s best friend and fellow high school athletic star, has been accused of murdering a 16-year-old student, Marcie Calder. Tony returns to Lake City, Ohio, the hometown he fled 27 years ago after his girlfriend, Allison Taylor, was strangled and Tony was accused of the crime. The humiliation and horror of the experience altered the course of his life, and Allison haunts him to this day.

The ingeniously constructed novel cuts back and forth between past and present tragedies, building suspense and allowing the reader to gain a deeper and deeper understanding of the complicated history that connects Tony, Sam and the unbelievably saintly Sue.

Patterson perfectly captures the Peyton Place-like atmosphere of a small Midwestern town where it’s impossible to keep anything about your private life a secret and high school sports are the local religion. “The night air was crisp and cold: It smelled faintly of burning leaves and Bermuda grass, popcorn oil wafting from the bleachers. . . . The cheers and the stomping of feet in the wooden stands carried the energies of a town of 13,000, a place unto itself, 30 miles from the Rust Belt city of Steelton, where fathers might work, but their families seldom went.”

If the novel has a flaw, it’s that it is haunted by the specter of the omnipresent O. J. Simpson murder trial. That over-publicized courtroom battle has raised the nation’s level of legal cultural literacy to the point where it’s no longer necessary for an author to preface expert testimony about DNA with lengthy explanations. And, in learning about Tony’s problems with the jury pool, (“It was less educated and less affluent: left behind by the flight of their economic betters, disadvantaged blacks and hard-pressed ethnic whites were overrepresented”) a reader cannot help thinking, “Been there, done that.”

Patterson capitalizes on our heightened consciousness by exploring the conflict that trial junkies often wonder about: How does a skilled defense lawyer live with his sometimes deplorable actions? “Sometimes I feel like God,” Tony answers, “and sometimes I feel like a sleazebag. At most times I feel like neither one.”

You can’t help liking the conflicted lawyer, yet it is difficult not to wince when he plays the race card, shifting blame to Ernie Nixon, the only African American in town. Tony justifies his action to Saul Ravin, the aging attorney who saved his life: “Dammit, you know as well as I do what my obligations are, and my feelings can’t get in the way. . . . It’s incompetence of counsel not to check out a defense.”

Fortunately, the inhabitants of Lake City, past and present, are realistic and disturbing. The denouement is powerful, if not completely surprising. If I am ever accused of murder, I’d like a lawyer like Tony Lord.