We are in the living room of Bell’s house just outside Sacramento, California. A perceptive, engaging woman of 48, she has turned an adjoining study into a small shrine to her late husband, who would have celebrated his 50th birthday five weeks ago. The room is decorated with his trophies: a Pulitzer prize hangs next to his HL Mencken award; also on the wall is a framed advertisement for The Kentucky Post. It reads: “There should be no fetters on reporters, nor must they tamper with the truth, but give light so the people will find their own way.” When Webb’s body was discovered last December, Bell says, this last item had been dumped in the trash.

Webb, one of the boldest and most outstanding reporters of his generation, was the journalist who, in 1996, established the connection between the CIA and major drug dealers in Los Angeles, some of whose profits had been channelled to fund the Contra guerrilla movement in Nicaragua. The link between drug-running and the Reagan regime’s support for the right-wing terrorist group throughout the 1980s had been public knowledge for over a decade. What was new about Webb’s reports, published under the title “Dark Alliance” in the Californian paper the San Jose Mercury News, was that for the first time it brought the story back home. Webb’s pieces were not dealing with nameless peasants slaughtered in some distant republic, but demonstrated a clear link between the CIA and the suppliers of the gangs delivering crack to the ghetto of Watts, in South Central Los Angeles.

His series of articles – which prompted the distinguished reporter and former Newsweek Washington correspondent Robert Parry to describe Webb as “an American hero” – incited fury among the African-American community, many of whom took his investigation as proof that the White House saw crack as a way of bringing genocide to the ghetto. Webb’s reports prompted three official investigations, including one by the CIA itself which – astonishingly for an organisation rarely praised for its transparency – confirmed the substance of his findings (published at length in Webb’s 1998 book, also entitled Dark Alliance). “Because of Gary Webb’s work,” said Senator John Kerry, “the CIA launched an investigation that found dozens of connections to drug runners. That wouldn’t have happened if he hadn’t been willing to stand up and risk it all.”

By 1997, Bell tells me, Webb – whose 30-year career had earned him more awards than there is room for in her study – had been reassigned to the Mercury News’s office in Cupertino.

“They had him writing obituaries,” she said. “The first story he had to file was about a police horse which had died of constipation.”

Webb, whose plans to become a journalist had begun when he was 13, but never included equine death notices, resigned from the Mercury News a few months later. Depressed, he became increasingly unpredictable in his behaviour and embarked on a series of affairs; he was divorced from Bell in 2000, though he remained close to her throughout his life and lived in a house in nearby Carmichael. Unable to get work from any major US newspaper, he spent the four months before his death writing for * a free-sheet covering the Sacramento area. To pay off his mounting debts, Webb sold the Carmichael property, where he was living alone, and arranged to move in with his mother.

When removal men arrived, on the morning of 10 December 2004, they found a sign on his front door, which read: ”Please do not enter. Call 911 for assistance. Thank you.” Webb’s corpse was found in the bedroom, with two gunshot wounds to the head.

When I first heard the news, I tell Bell, I was inclined to believe the conspiracy theories that still proliferate on the internet, suggesting that Webb had been assassinated – either by one of the drug dealers he’d met while writing Dark Alliance, or by the intelligence services who were supposed to police them.

She shakes her head.

“Looking back,” she says, “I think Gary had been obsessed with suicide for some time. And when he got something in his head, he was determined to do it. That was just the way he was.”

Webb, Bell explains, had written four letters explaining what he was about to do – one to her, one to each of their three children – and mailed them immediately before he killed himself.

“Why were there two bullet wounds?”

His former wife, her voice lowered to a whisper, explains that Webb missed with the first shot (which exited through his left cheek).

“The second bullet,” adds Bell, who has worked for more than 20 years in the area of respiratory therapy, “struck his carotid artery.”

“After Gary died,” she says, “a reporter from the LA Times came here. I felt weak and distressed; the whole thing was so fresh. She kept crying about how terrible it all was – by which I mean that she was, physically, crying. The story they printed was just awful. I felt she really trashed me. She said the paper wanted to make up for what it had done in the past. As it turned out,” she adds, “that was not their intent.”

Gary Webb was at his desk in the Mercury News’s Sacramento office, in July 1995, when he received a message to call Coral Baca, a Hispanic woman from the San Francisco Bay area, allegedly connected to a Colombian drug cartel. Baca claimed that a drug dealer with close links to the CIA had framed her boyfriend, who was also in the cocaine business.

“Gary didn’t take her seriously,” says Susan Bell, “because he was always getting calls alleging weird stuff about the CIA. So he blew her off. When she got indignant,” she adds, “he went to meet her.”

While police were preparing the case against her boyfriend, Baca alleged, officers had disclosed documents which revealed that one of her lover’s associates had been working for the Contras. Webb began to shift from cynicism to curiosity. With Baca’s encouragement, he started to investigate a large-scale Nicaraguan cocaine dealer named Oscar Danilo Blandón.

Webb was an assertive figure who drove fast cars and powerful motorcycles, hung heavy metal posters in his office and, at certain times in his life, smoked a fair amount of cannabis. Some editors regarded him as stubborn to the point of insolence. In and out of work, he had a reputation for taking risks. And yet, for all his Easy Rider tendencies, he was also a dedicated family man with an extraordinary appetite for researching minutiae.

Born in Corona, California, son of a conservatively minded Marine, he met Bell, whose father was a university lecturer, at high school in Indianapolis. When they married, she was aged just 21. Her husband began his career on The Kentucky Post, and rapidly proved himself to be the sort of character who can be a secretive agency’s worst nightmare: a full-blooded provocateur who liked to put the hours in at the library.

Webb joined the Mercury News in 1988, via the Cleveland Plain Dealer. In the six years he worked at its Sacramento office, he won the HL Mencken award, for a story exposing corruption in California’s drug enforcement agency, and his Pulitzer prize – won jointly, as part of a Mercury News team covering the 1990 Loma Prieta earthquake.

According to Walt Bogdanich, a former colleague on the Plain Dealer who has won two Pulitzers and now works for The New York Times, Webb was the best retriever of information from public records he has ever seen. Webb followed up Baca’s leads at the California State Library, examining Congressional records and FBI reports. What he found, he wrote later, “nearly knocked me off my chair”.

“He walked in one day,” Bell recalls, “and said, ‘You are not going to believe what I just found out.’ When he told me, I said it sounded crazy. He said: ‘No. The drugs went to South Central LA. There is a CIA connection and I can demonstrate it.'”

Webb put in a call to Robert Parry. Parry, the first reporter to write about the US authorities’ drug-running on behalf of the Contras, had survived a campaign by the White House to discredit first his story, then his reputation.

“I had to warn Gary that what he was looking at was probably true, but that he would run very big risks,” Parry recalls. “He thought I was being cowardly. I’m glad that I didn’t dissuade him, because it was important to get the truth out… but for Gary Webb, there was a very high price to pay.” Webb’s research took a year, in the course of which he received death threats.

I first heard about Webb eight years ago, I tell Bell, from the Paris-based journalist Paul Moreira. Moreira – a senior news producer for Canal Plus – has established a reputation for courage and independence of mind in his own foreign reporting, and was recently described by Le Monde as “the Che Guevara of news media”. Shortly before I left for Sacramento, Moreira, who knew Webb, had shown me unbroadcast footage which shows the French reporter making a phone call to a media commentator in the US, asking him about Webb’s death.

“I told Gary not to go near this story,” his source replies, in an emotional voice. “You do not understand the power of these people,” he adds, referring to the US intelligence services. “Do not quote me. Do not quote me on anything.”

“You sound very scared,” Moreira remarks.

“I am scared,” the voice replies. “Look at what happened to Gary Webb. Do something else with your life,” the voice urges. “Like enjoy it.”

By the time Webb began researching Dark Alliance, Bell was 38 and they had three children. Some might consider it an inappropriate assignment for a man with responsibilities.

“People told me that,” she says. “But Gary thought that if something was true, it should be told. He also had this inherent belief that the truth could not harm him. He really did believe that,” she says. “Back then.”

She pauses: “That said, he did sleep with a gun under his bed.”

‘Dark Alliance’ – both as journalism and as a book – is a convoluted narrative, but the crucial link it establishes is between the “agricultural salesman” Oscar Danilo Blandón, a Contra sympathiser with close CIA links, and his best customer, an LA drug dealer known as “Freeway” Ricky Ross.

Ross, currently serving life, was already infamous; he had been profiled in the LA Times in December 1994, by writer Jesse Katz, at a time when Ross was at liberty and in penitent mood.

“If there was an eye to the storm,” Katz wrote, “if there was a mastermind behind crack’s decade-long reign, if there was one outlaw most responsible for flooding LA’s streets with mass-marketed cocaine, his name was Freeway Rick.

“Ross,” his report went on, dealt “on a scale never before conceived,” with “a staggering turnover” of “50 to 100 kilos of cocaine a day”.

Webb established incontrovertible links * between Ricky Ross and Blandón who, two years later, would betray Ross to the authorities.

By the late spring of 1996, Webb was ready to publish. Cuts and amendments were made at the request of Ceppos, executive editor of the Mercury News, and Webb’s immediate editor Dawn Garcia, among others. Then, in August the same year, the first of three instalments of “Dark Alliance” appeared.

“For the better part of a decade,” it began, “a San Francisco drug ring sold tons of cocaine to the Crips and Bloods street gangs of Los Angeles and funnelled millions in drug profits to a Latin American guerrilla army run by the US Central Intelligence Agency.”

The story had little immediate impact. But “Dark Alliance” was also posted on the Mercury News’s website, with the image of a crack smoker superimposed on the CIA badge. Within weeks, the site was attracting up to 1.3m hits per day. The story was picked up by black talk-radio stations. The legendary civil-rights activist Dick Gregory was arrested while he protested outside the CIA’s headquarters; Gregory began referring to the organisation as “Crack in America”. Webb – whose article had never alleged that the CIA deliberately targeted any ethnic group – became a national celebrity.

In an unprecedented move, the then CIA director John Deutch was dispatched to address community leaders in the Watts district of LA. Film of this encounter survives. “This is an appalling charge,” says a tense-looking Deutch. “It says the CIA helped introduce poison into our children. Nobody who heads a government agency can let such an allegation stand.”

“Allow Gary Webb to be there [in the CIA investigation],” a heckler shouts.

Deutch declines the invitation.

Webb undeniably made mistakes of detail and emphasis in the newspaper version of “Dark Alliance”. The consensus, insofar as one exists, is that he probably overstated both the amount of drug money made by Ross and Blandón, and the percentage of those profits diverted to the Contras. Although Blandón’s cartel was undoubtedly one of the first to bring crack to LA, Webb was almost certainly suffering a rush of blood when he described the group as “the first pipeline” into the city.

But his central thesis – that the CIA, having participated in narcotics trafficking in central America, had, at best, turned a blind eye to the activities of drug dealers in LA – has never been in question.

Jack Blum, who was the lead investigator for Senator John Kerry’s Subcommittee on Terrorism, Narcotics and International Operations, which produced a highly damning 1989 report on drug-smuggling in the guise of national security, is one of several commentators to have questioned aspects of Webb’s original reporting.

“But that,” pointed out Blum, who is now a Washington attorney, “in no way – in no way – diminishes the wrongness of what these bastards did. And the importance of exposing them. Work with a bunch of drug dealers to run guns? I mean – please.”

The response from the American press took two months to arrive. When it did, beginning with The Washington Post, it shocked Webb’s critics as much as his many admirers.

Peter Kornbluh, senior analyst with the George Washington University’s National Security Archive, was one of the first to suggest that Webb had overplayed his hand in the Mercury News version of “Dark Alliance”. He recently told the American Journalism Review (whose scrupulously researched piece, by Susan Paterno, is the only serious documentation of the Webb case I could find anywhere in the orthodox American media) that Webb’s critics in rival newspapers, “quoted these CIA guys – who had a tremendous amount to hide – as though they were telling the truth. Gary Webb became, quite unfairly, the victim of one of the most extraordinary examples of piling on by the mainstream press, ever.”

Going to the CIA to ask if they’ve ever profited from drug sales in Los Angeles, I suggested to Kornbluh, is rather like asking Fagin if he has ever picked a pocket.

“Exactly,” replied Kornbluh, who – referring specifically to the LA Times, said he is “baffled as to how they could be so gullible. I remain astounded by the editorial decisions they made.”

The first effect of the onslaught was to ease the pressure on the CIA. One instalment of the LA Times’s 18,000-word rebuttal of Webb’s piece, published in October 1996, sought to minimise the importance of his key witness, Ricky Ross. It was written by Jesse Katz, the same reporter who, less than two years earlier, had described Ross’s conglomerate as “the Wal-Mart of crack dealing”.

“Although Ross had become a millionaire by 1984,” Katz now wrote, “the market was so huge by then that even a dealer of his stature could seem dwarfed… How the crack epidemic reached that extreme, on some level,” he continues, “had nothing to do with Ross”.

If the antagonism of competing publications was predictable, what happened to Webb within his own newspaper was not. The normal process is, or should be, that a reporter files a story and is robustly challenged by his paper’s lawyers and editors – who, if satisfied that the report is accurate – publish, then defend the writer to the hilt. Should these editors subsequently deem the story to have been fatally flawed, they take the consequences. This did not happen in Webb’s case.

Gary Webb, friends say, was a far more combative character than either the Mercury News’s executive editor Ceppos or page editor Garcia. Ceppos initially defended Webb, and reportedly showed up at an in-house party wearing a military helmet. But once the flak really started to fly, from the nation’s grandest newspapers, Ceppos – having come under exactly what form of pressure it is difficult to know – printed a retraction which Webb dismissed as spineless. Both sides were left angry and disappointed.

“Gary was given the choice of relocating either to San Jose,” says Bell, “or to Cupertino”. Working in San Jose would have meant daily contact with what Bell describes as “people he did not want to be with”. Webb chose the second option. By the autumn of 1997, on medication for clinical depression, he was given leave of absence from the paper. Then, on 10 December, he resigned.

Webb took a modestly paid, low-profile job as an investigator with the California State Legislature. His erstwhile editors on the Mercury News, meanwhile, saw their careers thrive. In 1997 Ceppos was awarded the US Society of Professional Journalists’ National Ethics Award. Two years later, he was promoted to Vice President of Knight Ridder, the Mercury News’s parent company; he retired from this position last month. Garcia is deputy director of the John S Knight Fellowships in Journalism at Stanford University.

Ceppos and Garcia have long since lost any taste for public discussion of “Dark Alliance”. Ceppos failed to reply to one phone message and six emails. Garcia responded by email but declined to speak on the record about the editing process of Webb’s series.

The CIA Inspector General’s report, commissioned in response to the allegations in “Dark Alliance”, was published in the autumn of 1998. It found that CIA officials ignored information about possible Contra drug dealing; that they continued to work with Contra supporters despite allegations that they were trafficking drugs, and further asserted that officials from the CIA instructed Drug Enforcement Agency officers to refrain from investigating alleged dealers connected with the Contras.

By a fortunate coincidence of timing, the report was released on a day when the Monica Lewinsky scandal dominated every front page in the country. As a result, some major US newspapers ignored its findings completely, while others relegated a brief summary to their inside pages.

“I think the behaviour of the media in all of this has been amazing,” says Bell. “I believe that Americans, as a nation, are mainly concerned with living their happy little lives. And this is not a happy story – or,” she adds, “a little one.”

Webb’s experience came as no surprise to Jack Blum, senior prosecutor for the Kerry Committee. For two years, Blum and Kerry supervised the interrogation of dozens of witnesses who described CIA-related drug deals in central America. Their explosive report, which appeared in 1989, was either ignored, or marginalised, by the American press.

“They tried to make us look like crazies,” says Blum. “And to an extent, they succeeded.”

“It was like someone had made a terrible noise, or a terrible smell, in a small room,” recalls Jonathan Winer, Kerry’s chief senate staff investigator . “Everyone got out and left the person who had made the noise – issued the report – alone. But the report was correct. It was truthful. It was accurate. And it was ignored by the US media, for all of those reasons. We were dismissed as a bunch of nuts.” Newsweek called Kerry a “randy conspiracy buff”.

“I think Kerry learnt a lesson from all this,” reporter Robert Parry says. “Which was that, if he wanted a future within the political establishment of the United States, then he should concentrate on other aspects of life.”

Webb, unlike Blum or Kerry, had to face his difficulties alone. His was the story of a man who gains information of wrongdoing, then, attempting to act in the public interest, seeks protection from his superiors, and the forces of law, and does not receive it. The whole business, I suggested to Blum, has echoes of a classic Alfred Hitchcock plot.

“That’s right,” says Blum. “Gary Webb was left to fend for himself. We had been here before.” He cites the case of Alfred McCoy, now Professor of South East Asian Studies at the University of Wisconsin.

“As a PhD student, McCoy went to Vietnam and built an absolutely damning case about the CIA’s involvement with trafficking heroin. * The agency’s response was to try to prevent him from getting his doctorate, then block his advancement in the academic world. They failed because the climate was more sceptical then. But you say – dear God. Can these things possibly be?”

The significant legacy of the Webb case, “the reason this whole affair remains so significant today,” Blum says, “is this: the knowledge that, if one individual dares raise such serious issues, they risk confronting a tremendous apparatus that is prepared to whack them hard, and there is very little they can expect by way of support. Look at the way the US press reports on Iraq. The complete lack of desire to ask the difficult questions makes me want to scream.”

As Webb would tell a friend, after he had been ostracised: “You have to look out, when the big dog gets off the porch.”

Webb, according to Bell, was a man who, more than most, found that his mood and self-esteem fluctuated in accordance with his professional fortunes. In February last year he was laid off by the State Legislature.

“He rang me up that day. It would have been our 25th wedding anniversary,” Bell recalls. “He was crying. He kept saying that he would never get another job in journalism.”

Bell and her children helped Webb prepare 50 packages containing cuttings and his CV which they sent out to newspapers all over the US. By this stage, he was prepared to work as a jobbing reporter. There were no offers. Webb had become, as somebody put it, “radioactive”.

In the final few months of his life, Bell says, Webb became increasingly withdrawn. Relationships with other women ended badly. He stayed home, playing computer games, and began smoking cannabis heavily. When his medical insurance expired, he stopped taking his antidepressants.

“He told me, not long before he died, that he didn’t want to get up in the mornings,” she says. “He definitely was depressed. But the biggest loss he had was the writing. He made that very clear. He told me: ‘If I can’t do what I want to do, what’s the point?’ ”

Webb’s condition exacerbated his natural recklessness.

“He started having motorcycle crashes,” Bell says. “He had six in a short period of time.” On one road trip, in 2001, he came off the motorcycle and split his helmet open. “He told the guys with him he was fine,” she recalls, “got back on the bike, then passed out, half an hour later. He crashed and shredded his clothes, face and body on a barbed-wire fence.” He was taken to hospital by air ambulance.

With hindsight, Bell says, “the signs were there. One time he called me and he said: ‘I have this plan that will benefit us both.’ I realise now he was thinking about suicide.”

On the last day Webb was alive, his motorbike broke down while he was moving to his mother’s house. A passing motorist – a heavily tattooed young man – gave him a lift home, then returned and stole the motorcycle, which police recovered from him three days after Webb’s death.

“It sounds crazy,” says Bell, “but having his motorbike stolen was the last straw. He was so depressed. It was just more than he could take.”

Webb came home and put his belongings in order, dropping his Kentucky Post poster in the bin. He placed his keys and ID cards on the kitchen table, together with a cremation certificate he had purchased for himself. He went into the bedroom, and picked up a .38 that had belonged to his father. When his body was found, The Good, the Bad and the Ugly was on the DVD machine, and his favourite CD, Ian Hunter’s live album Welcome to the Club, was in the CD player. His death was especially traumatic to the family since – as the coroner said – it could not be established whether he died instantly, or bled to death.

His corpse was discovered on the seventh anniversary of his resignation from the Mercury News. “Do you think that a part of him did this out of revenge?” I ask Bell. “To get back at his editors?”

“Not revenge,” she says. “Despair.”

At the commemorative service for Webb, held at the Doubletree Hotel in Sacramento, Bell read out the letter Webb had written to his son Eric, now 17.

“If I had one dream for you,” he wrote, “it was that you would go into journalism and carry on the kind of work I did – fighting, with all your might, the oppression and bigotry and stupidity and greed that surrounds us.”

Webb had already been cremated and his ashes scattered in the bay off Santa Cruz two weeks before. There was no coffin, casket or tombstone. If he could have chosen his own epitaph, it might have been a line from the letter he posted to Bell, immediately before he killed himself: “I do not regret,” Webb told her, “anything that I have written.” *

‘Dark Alliance: The CIA, The Contras and the Crack Cocaine Explosion’ is published in the UK by Seven Stories Press, priced £11.99