In May 2005, readers of Spokane's Spokesman-Review awoke to a startling story: Spokane's Republican mayor Jim West had been leading a double life. In public, he was a conservative politician who had co-sponsored legislation forbidding gays from teaching in public schools. But in private, the paper reported, West spent hours trolling for young men on the Internet, sometimes using the trappings of his office as bait to lure them into more intimate relationships.

The story briefly made national headlines and ultimately destroyed West's political career. But FRONTLINE producers Rachel Dretzin and Barak Goodman look beyond the headlines to find a story that is much less clear than it initially seemed. Featuring access to all sides of the story and close readings of the mayor's Internet chats and other documents, "A Hidden Life" examines a man's struggle with his sexual identity, a newspaper's controversial online sting, and the growing tension between a politician's private life and the public's right to know in an age of online communications.

"We wanted to know, 'Do we have a mayor trolling on the Internet for underage boys?'" Spokesman-Review reporter Bill Morlin tells FRONTLINE of the paper's decision to hire a consultant to pose as a 17-year-old boy on a gay web site. The consultant then sought out the mayor to see how far West would go. "The intention wasn't to bait anyone," says Morlin. "The purpose of our investigation was a search for the truth."

The newspaper's investigation began as an attempt to reckon with a shameful secret from the past -- a wave of child molestation that swept through Spokane in the 1970s, implicating men in some of the city's most trusted institutions: the Catholic Church, the Boy Scouts, and the sheriff's office. One of those men was a decorated Vietnam veteran, Boy Scout troop leader and sheriff's deputy named David Hahn, who committed suicide in 1981 after being accused of sexually abusing boys. Early in the Spokesman-Review investigation, Bill Morlin discovered that Hahn's close friend at the sheriff's department and the Boy Scouts was future Mayor Jim West. "Sources that I interviewed said that [Hahn and West] were peas in a pod," Morlin tells FRONTLINE. "They were inseparable."

In the course of trying to substantiate leads tying the mayor to the sexual abuse from the 1970s, Morlin received a tip from a 20-year-old college student who described meeting West in a gay Internet chat room. The source claimed to have gone on a date with the mayor that ended with a sexual encounter in a parking lot. "In my view, these stories were supportive of one another," says Spokesman-Review Editor Steven Smith. "If we have allegations that Jim West abused young boys 25 or 30 years ago, and we have an indication that he's pursuing young boys now, then each of those elements supports the other." Just before publication, the paper found two men who said they had been molested by West in the 1970s. The paper decided to publish the allegation despite the fact that its main source never formally mentioned West in several previous statements about his abuse.

In the days and weeks after the scandal broke, West admitted visiting gay chat rooms, but he strongly denied the allegation that he had molested boys. "That's the preconceived notion The Spokesman-Review went into the story with," West tells FRONTLINE in his most in-depth television interview about the scandal. "They were convinced that I had abused young children years ago. In their mind, this was the main story. And in fact I didn't." To West, the newspaper's story might have begun as an attempt to reckon with Spokane's abuse history, but it had evolved into a more personal battle with The Spokesman-Review and its editor, Steven Smith. "The only way he can prove he's right is by running me out of office or killing me off," says West.

In the end, The Spokesman-Review's investigation was unable to turn up substantial support for the charge that West had molested boys in the 1970s or courted underage men online. "While we never confirm sexual activity with underage boys, what we find ourselves dealing with is abuse of office," Steven Smith tells FRONTLINE, speaking of the paper's evidence that West offered unpaid internships in the mayor's office to men he met online. "The mayor appears to have been offering rewards and benefits and even jobs in return for sexual favors." That impression was strengthened when a young man came forward to say that West had appointed him to the city's Human Rights Commission because West had a romantic interest in him.

In December 2005 -- after 189 stories in The Spokesman-Review and the city's first ever recall election -- Mayor West was voted out of office in a landslide. "The demise … was absolutely Shakespearean," says David Ammons, who covered West's career for the Associated Press. "I would say he was the most important Republican in the state for a while. And now he's exiled in disgrace." West himself later tells FRONTLINE: "If what was printed in the newspaper and said on the radio [were] true, I'd abandon me. I'd say, 'How could I be near this person?' But I knew that it wasn't and the majority of my friends did too."

On February 16, 2006, after completing a 10-month investigation, the FBI announced that it had found no evidence to charge West with abuse of office. Five months later, on July 22, West died of cancer.