BIG TROUBLE: A Murder in a Small Western Town Sets Off a Struggle for the Soul of America.<i> By J. Anthony Lukas</i> .<i> Simon & Schuster: 592 pp., $32.50</i>

On a snowy evening in late December 1905, as former Idaho Gov. Frank Steunenberg opened the wooden gate to his comfortable lamp-lit home, an explosion shattered the air, demolishing the gate, splintering yards of boardwalk and tearing the governor’s body apart. The blast could be heard for miles around, and the reverberations shook the nation.

After a massive manhunt in the small, booming town of Caldwell, Idaho, the authorities arrested a self-described itinerant sheep dealer, who was registered at the Saratoga Hotel under the name Thomas Hogan. It soon developed that he hadn’t sold any sheep, that he had bomb-making paraphernalia in his hotel room and that his name was Harry Orchard (or, after further probing, Albert E. Horsley). Hogan-Orchard-Horsley’s triple identity is, in a sense, a metaphor for the multiple levels on which this political murder mystery unfolds.

The late J. Anthony Lukas, who committed suicide in the spring, was one of America’s best and most respected journalists. He won one Pulitzer Prize for his New York Times reporting and a second for his book “Common Ground,” a remarkable study of families affected by court-ordered busing in Boston. He was drawn to the subject of his last book because it represented a moment when America was almost torn apart by class warfare. His book, mammoth in size and meticulous in detail, is a painstaking dissection of that pivotal moment.

When Orchard claimed that he had been acting as an agent for the inner circle of the militant Colorado-based Western Federation of Miners and, specifically, for its leaders, William “Big Bill” Haywood, Charles Moyer and George Pettibone, a team of Pinkerton detectives kidnapped all three from their Denver homes (or in Haywood’s case, from his sister-in-law / girlfriend’s apartment) and took them by special train to Boise to stand trial. (As Allan Pinkerton, the agency’s founder, said of an earlier case: “It was kidnapping, but the end justified the means.”)

The case immediately became a cause celebre and an O.J. Simpson-type Rorschach test for the forces of labor, socialism and the left, who were convinced that the men had been unjustly accused as part of an effort to destroy labor, and for the mine owners, ranchers and mainstream press, many of whom thought that militant murderers were getting their just deserts. It was this confrontation, set against the broad background of a still relatively wild and economically stratified West, that led Lukas to believe that the fight came close to class warfare.

No one familiar with the controversy, it seemed, was neutral. The defense assembled a brilliant team led by Edmund Richardson and Clarence Darrow, the famed “attorney for the damned,” and the prosecution featured just-elected U.S. Sen. William Borah.

“Big Trouble” is filled with captivating (if sometimes distracting) cameo appearances by such future and current celebrities as Walter Johnson, who, then 20, was pitchingfor a minor league baseball team just 75 miles north of Boise, and 28-year-old Ethel Barrymore, in town for a one-night performance of “Captain Jinks of the Horse Marines.” (After attending the trial, she called Orchard far better- and cleaner-looking than the one-eyed Haywood who, she told reporters, made her shudder.) But thanks in part to a treasure trove of reports to the Pinkerton detective agency and to the absence of similar documents or manuscripts from the defendants or the defense, the book’s most clearly rendered central character is James McParland, the master investigator and coordinator for the prosecution, a man whom Lukas respectfully, ironically, playfully and consistently calls the “Great Detective.”

As Lukas describes in fascinating detail, McParland came to international fame as the man who bravely infiltrated and destroyed the Molly Maguires, the secret society of Irish coal miners in Pennsylvania that took the law, and punishment, into its own hands in the years after the Civil War. His testimony led to 20 men being sentenced to death; 10 were hung on June 21, 1877, Black Thursday in some Irish American circles. McParland’s story was told and retold in popular journals and pulp fiction. Sir Arthur Conan Doyle even contrived a fictional encounter between McParland and Sherlock Holmes in “Valley of Fear.”

Scores of books have questioned the veracity and tactics that the Great Detective used to persuade Orchard to implicate the mine worker leaders and to remove the defendants from Colorado without due process of law. Some have accused McParland of excessive pressure in procuring Orchard’s confession, in which he admitted to no fewer than 18 murders. But whatever his failings, McParland, according to Lukas, had substantial evidence on his side and acted reasonably honorably.

Honor, however, was a decidedly relative commodity in an America torn apart by the war between capital and labor. In Lukas’ account, all of the principal figures, however legendary they became, were deeply flawed--or in fairness to the era, perhaps it is more accurate to say that they were prepared to sacrifice ethics (and lives) to what they were pleased to consider higher goals. “It is war,” one reporter observed, “and the methods of war have been adopted.” Lukas offers substantial evidence that union leaders killed scores of nonunion laborers and blew up mines in the Coeur d’Alene region in the cause of unionization and better wages.

In April 1899, the miners-union tried to close down the region’s most anti-union mine, Bunker Hill. Some 150 heavily armed union members turned workers away from the mines and seized the company’s tramway. The company’s manager wired Steunenberg for help, but the governor, who had been elected with labor support, urged arbitration. The next day, hundreds of men, many with rifles, some with masks, seized a Northern Pacific train, loaded it with 80 wooden boxes, each containing 50 pounds of dynamite, and ordered the engineer to head for a town called Wardner, the site of the Bunker Hill mine. At Wardner, they took several prisoners, shot and killed one of them and placed 60 boxes of dynamite at three strategic locations. The resulting explosion effectively destroyed the Bunker Hill complex.

Defying his union supporters, an outraged Steunenberg vowed to “totally eradicate from this community a class of criminals who have for years been committing murders and other crimes in open violation of the law.” He declared martial law, and the federal government sent in a “colored” regiment (apparently to ensure that they wouldn’t bond with the rioters) to restore order. The soldiers rounded up almost the entire community of Canyon Creek, and all of the men in Burke, loading 243 men into four boxcars and taking them to Wardner, where they were herded into an old barn. Within a week, a series of other raids brought the number of prisoners to more than 1,000. Those who couldn’t fit in the barn were put in boxcars. When the local authorities objected, they were arrested or removed from office. Steunenberg’s personal representative, Bartlett Sinclair, replaced the sheriff with a man of his own choosing. Then Sinclair insisted that all miners seeking work must obtain permits from the new sheriff certifying that they were law-abiding citizens.

From that time forward, there were threats on Steunenberg’s life, threats that continued after he left office in 1901. According to Orchard, the union leaders wanted to kill Steunenberg as a grizzly warning to others who might try to oppose their will.

Steunenberg and the labor leaders were not the only ones who did not play by Marquess of Queensberry rules. After the labor leaders were arrested for killing Steunenberg, Idaho’s top political leaders disguised the embarrassing and perhaps unethical fact that mine owners were helping to pay for the prosecution; the Pinkertons, who had “kidnapped” the defendants, planted spies in Darrow’s defense team (Darrow may also have planted spies with the Pinkertons); Darrow and his colleagues probably paid key witnesses to stay away from the trial and, possibly, bribed at least one juror. Borah was implicated (though not convicted) in a fraudulent scheme to aggregate and sell thousands of acres of government timberland, a scheme that almost certainly was orchestrated, in part, by Steunenberg.

No one fought harder for political balance than then-President Theodore Roosevelt, but he soon found out it was impossible to be neutral in the age of open warfare between labor and management. Though convinced that the union leaders were almost certainly guilty of murdering Steunenberg, Roosevelt tried to assure a fair and credible trial. When he heard that the mine owners might be funding the prosecution, he wrote to Idaho’s new governor, Frank Robert Gooding, and insisted that the trial be financed by the local government alone, not by industry. When Roosevelt criticized one side, he tried to criticize the other as well. But that effort, which led some papers to call him “the man on two horsebacks,” was doomed to failure. Muckraker Ray Stannard Baker argued that it was a way of skirting the hard issues in the labor-management wars.

Roosevelt lost his balance in October 1906 when railroad magnate E.H. Harriman privately accused him of a desperate last-minute effort to raise $250,000 for the 1904 presidential campaign, an effort that culminated in a secret breakfast meeting at the White House with a group of the richest industrialists and financiers in the nation. Furious, Roosevelt wrote an internal memo denouncing Harriman in vicious terms and calling him “at least as undesirable a citizen as [socialist leader Eugene] Debs, or Moyer, or Haywood.”

No doubt it seemed like another balanced statement. But the union defendants saw it differently when Roosevelt, in response to a news story revealing Harriman’s accusations, made the memo public six months later. Darrow and his colleagues seized on the letter as an outrageous attempt to influence the outcome of the trial. The defendants’ supporters around the country organized a series of demonstrations. Marchers wore badges saying “I Am an Undesirable Citizen” and “Haywood is in jail for not contributing toward Roosevelt’s Campaign Fund. Harriman did and he is at large.”

The union leaders were to be tried separately, starting with Haywood. The courtroom itself had the unique flavor of the turn-of-the-century American West with the 12 male jurors in rocking chairs, chewing tobacco and spitting the residue into spittoons. By Lukas’ account, most observers, including the judge, thought that Haywood was guilty. But the prosecution’s case had one major flaw: Though Orchard was a highly credible witness, there was no other witness who would corroborate his story. It was widely believed that the defense had paid off two men who could support his story and had hidden one out of the prosecution’s reach. If so, it was an effective, if illegal, strategy. The law required substantial corroboration of an accomplice’s testimony because it may have been procured by the state through the promise of leniency. Haywood’s defense also benefited from exceptionally effective closing arguments by both Richardson and Darrow.

After a day of intense debate, the jury acquitted Haywood. Writing privately this time, Roosevelt called the verdict “a gross miscarriage of justice” and concluded, “I suppose the jury was terrorized.” That conclusion was more than hyperbole. Lukas presents substantial evidence that threats were issued and that jurors’ families feared for their lives if Haywood was convicted. “Viewed from this perspective,” Lukas notes, “the trial’s crowning irony was that the more the jurors believed the prosecution’s case that the WFM slaughtered its enemies, the less likely they’d be to incur that wrath by voting for conviction.”

But many people on the left agreed with anarchist leader Emma Goldman and two of her colleagues, who happily and mischievously sent a telegram to the president. “Undesirable citizens victorious,” it said. “Rejoice.”

For all of its strengths, “Big Trouble” lacks the detailed focus and human intimacy of Lukas’ best journalism. One wishes he could have covered the trial, interviewed the participants and lived in the community. But the historian, unlike the reporter, is limited to facts and thoughts as revealed in the articles, books, manuscripts and documents that survive. Lukas was the most tenacious of researchers; unfortunately, the extant primary sources from the defense were not complete enough to enable his enormous talent to render a fully satisfying dramatic narrative.

While describing many of its major participants, Lukas does not provide a sustained analysis of the issues of class warfare of the era. But one interesting and central dimension of the battle that “Big Trouble” describes is the effect that it has had for almost 90 years on the way newspapers and, later, popular literature have characterized the major participants in the saga. Those who stood with the workers, not just supporters of socialism and labor but the left more broadly, have tended to treat Haywood (who later fled to Russia on a faked passport and willed that his ashes be split between Russia and the Chicago grave site of the Haymarket anarchists) with a degree of romantic sympathy. The Pinkertons and Orchard, by contrast, have been objects of contempt.

By unearthing long-lost documents and studying events with his celebrated devotion to fairness and truth, free of the assumptions, prejudices and passions of another era, Lukas found that the miners’ union and Haywood, whatever their other strengths and whatever the legitimacy of their cause, were almost certainly coldblooded killers. One cannot but wonder whether those caught up in the political wars of other eras, including our own, are equally myopic. Tragically, Lukas is no longer with us to examine the myriad questions that emerge from this seminal study of one of America’s greatest trials.