WASHINGTON — Tom Fitton and the lawyers at Judicial Watch unearthed a bombshell.

Scouring through a cache of documents tied to the Sept. 11, 2012, terrorist attack that killed four Americans at the U.S. Consulate in Benghazi, they discovered an email with the subject: PREP CALL with Susan: Saturday at 4:00 pm ET.

What followed was a list of Sunday news show talking points that a top Obama administration official prepared for Susan Rice, then ambassador to the United Nations, "to underscore that these protests are rooted in an Internet video, and not a broader failure of policy."

Congressional Republicans had investigated Benghazi for more than a year by the time Judicial Watch got the email through a Freedom of Information Act lawsuit. But the White House's role in shaping the early, false narrative provided critics with a smoking gun. The email was used to justify a select House committee that grilled Secretary of State Hillary Clinton for 11 hours straight.

Yet through thousands of documents and various inquiries into Clinton's State Department, something struck Fitton as curious: the lack of direct communication. "I was thinking maybe she just didn't email," he recalled. "So just to be sure, we asked again and sued again because we were stonewalled. And sure enough . . ."

Clinton's use of a private, unauthorized email server — revealed during the House investigation — has plagued her campaign for president, fueling widespread feelings that she is untrustworthy.

Most Americans haven't heard of Judicial Watch, but the conservative group has been a principal force behind Clinton's trouble, prying free government documents through a withering deployment of FOIA requests and lawsuits.

When government agencies stall, Judicial Watch sues.

The group's lawsuits are responsible for the release of thousands of Clinton emails that were on her server, and on Friday, the State Department was to begin releasing thousands more that were discovered in the FBI inquiry.

Next week, Clinton, under court order, must provide written answers to 25 questions posed by Judicial Watch.

Financial contributions are pouring in and expansion plans are under way, positioning the group with about 50 staffers and an operating budget of $35 million for an even more aggressive role should Clinton win the election.

"It's a long ballgame," said Fitton, author of a new book, Clean House: Exposing our Government's Secrets and Lies. "One of the secrets to our success is we don't go away."

• • •

A PR machine, Judicial Watch issues a daily stream of dramatic news releases and makes Fitton and other officials fixtures on Fox News and in conservative publications. It encourages followers to amplify messages on social media, write guest editorials for local newspapers or call into radio talk shows.

The group's history is riddled with misses, rejected by many as a well of conspiracy theories, a cog in what Clinton once deemed the "vast right-wing conspiracy."

Critics say the ongoing Clinton investigations, which include a focus on access Clinton Foundation donors had to the State Department, are more flash than substance and that Judicial Watch selectively releases information.

"They have their agenda and their information comes out in a way to pursue that agenda," said Norm Ornstein, resident scholar at the conservative American Enterprise Institute. "I give them credit because they've figured out how to use the legal system to accomplish a lot of political ends. And they have a very good understanding to how the press reacts to all this."

But a range of observers say Judicial Watch has advanced transparency and raised legitimate questions about Clinton's judgment and handling of sensitive information. Polls confirm the email issue has hurt Clinton, who was deemed "extremely reckless" in an FBI probe that did not recommend criminal charges.

"If there's no accountability for Mrs. Clinton on this issue, it's the end of transparency in government," Fitton said. "That's a slight overstatement, but it's significant. Because if government officials can take the position that, 'I'm just going to do all my work on a private system' and keep it away from the American people, then you have no accountability left. She defrauded us. She defrauded the American people."

• • •

On a Friday morning, Fitton sat in a conference room at Judicial Watch's offices near the Capitol in southwest Washington. He has been the group's president since 1998. An athletic figure with gray-streaked hair and a gap between his front teeth, the 48-year-old wore a green polo and jeans. He has a laid-back demeanor and speaks in measured tones, even as he unabashedly describes the Benghazi-turned-Clinton-email issue as "the most significant nongovernmental investigation in recent American history."

It's a stark contrast from Judicial Watch's founder, Larry Klayman, whom the Washington Post described as "like an anarchist flagpole sitter with a law degree, inclined toward the grand gesture and the bald overstatement." The West Wing character "Harry Klaypool" wasn't far off the mark, using frivolous lawsuits in an attempt to bring down Josiah Bartlet's administration.

Formed in 1994, Judicial Watch drew its name from a belief that the courts needed a watchdog and that the judiciary could be used as a watchdog over the rest of government through litigation. "Because no one is above the law," says the group's motto. "To this end, Judicial Watch uses the open records or freedom of information laws and other tools to investigate and uncover misconduct by government officials and litigation to hold to account politicians and public officials who engage in corrupt activities."

Klayman zealously pursued the Clinton administration, jumping on "Filegate," the probe into allegations that White House staff obtained FBI files on opponents, and "Chinagate," a 1996 scandal that focused on whether China funneled illegal donations to the Democratic Party.

None of it stuck to the Clintons, but Judicial Watch's work contributed to the air of scandal that trails them today.

A showman with a tenacious streak, Klayman expanded his reach with the help of U.S. District Judge Royce Lamberth, a Reagan appointee who abhorred government incompetence and was randomly assigned Judicial Watch's early cases. "Maybe God had something to do with it," Klayman, who now lives in Boca Raton, said in a telephone interview.

With subpoena power granted by Lamberth, Klayman went after any Clinton official he could. When James Carville called him a "little twerp," Klayman hauled him in for a deposition.

Along the way, Klayman landed victories, notably establishing links suggesting Commerce Department officials carved out spots on coveted international trade missions for business people who donated to the Democratic Party.

Judicial Watch's profile grew, which led to better fundraising. A key early supporter was Richard Mellon Scaife, a Pittsburgh billionaire who bankrolled various anti-Clinton crusades.

(The tax-exempt group does not publicly disclose its donors despite pushing for transparency. Fitton, noting that other nonprofits do the same, said there are 400,000 active contributors and Judicial Watch has an email list of nearly 1 million.)

During the 2000 presidential election recount, Klayman teamed up with news organizations to determine what went wrong. "Republicans were having heart attacks because we opened up the ballots," he said. "I did it because I thought the citizens of Florida should know who really won."

He rankled Republicans further by going after George W. Bush's administration, joining the Sierra Club in a suit to open up records of the energy task force convened by Vice President Dick Cheney. Judicial Watch also sued Cheney and his former company, Halliburton, over alleged fraudulent accounting practices.

"People forget they were really aggressive under Bush," said Danielle Brian, executive director of the nonpartisan Project On Government Oversight. "They were at least equal-opportunity gadflies."

Klayman left Judicial Watch in 2003 to run for U.S. Senate in Florida but was trounced in the GOP primary against Mel Martinez. In 2006, he sued Judicial Watch, alleging mismanagement and breach of contract. No one was surprised. "Litigious Larry" once sued his mother over $50,000 he paid for nursing care for his grandmother.

In an interview, Klayman took a shot at his old partners, saying they have not shown a balance in going after Republicans. But he also praised Judicial Watch on the Clinton matters. "They've gotten some good documents," he said. "I'm glad they are out there."

• • •

"The FBI director should be ashamed of himself. It was a political decision."

Fitton was at his office talking about the fallout from the Clinton email scandal. FBI director James Comey's decision not to seek criminal charges caused an uproar on the right and rankled some FBI insiders. Fitton contends Comey overlooked questions of obstruction and destruction of records.

Clinton, while having apologized, has dismissed the broader questions, and she and her campaign have cast Judicial Watch as purely partisan. Media Matters, a liberal group founded in 2004 by former Clinton antagonist David Brock, has attacked news outlets for picking up on the material uncovered by Judicial Watch.

For all its reliance on the black and white of government documents, the group has fed a perception of being conspiracy theorists. Klayman helped stir the idea that White House attorney Vince Foster was murdered in 1993 — an unproven theory that still circulates. (Donald Trump earlier this year called the death "very fishy.") In 2015, Judicial Watch claimed, without evidence other than unnamed sources, that ISIS was operating a camp in Mexico, a few miles from El Paso.

But Judicial Watch continues to dig up newsworthy information, helping propel, for instance, a 2014 controversy over the IRS targeting tea party groups.

A major focus lately has been access Clinton Foundation donors had to the State Department. A 2009 email showed that Clinton Foundation executive Doug Band tried to put a donor in contact with the ambassador to Lebanon to talk about his business interests there. The Clinton response: Band was wearing his hat as Bill Clinton's personal assistant.

Another email showed that Clinton aide Huma Abedin helped facilitate a request from the crown prince of Bahrain, a Clinton Global Initiative supporter, for a meeting with the secretary. "Good friend of ours," Band wrote to Abedin.

Clinton's campaign scoffed at any suggestion of impropriety and noted the role of the secretary of state is to meet with foreign leaders.

"Once again this right-wing organization that has been going after the Clintons since the 1990s is distorting facts to make utterly false attacks," a spokesman told reporters in August.

Fitton smiles at such retorts.

"It's so '90s what they are saying, 'Oh this anti-Clinton group.' Back in the 1990s they were able to isolate and intimidate investigators, reporters and that doesn't work anymore. The Internet revolution has made access to the information much more accessible."

He vowed Judicial Watch will aggressively seek transparency no matter who wins the White House. But clearly Clinton is good for business, even if Judicial Watch's supporters hope she can be stopped.

"Send the pit bulls loose . . . great work," an Atlanta man wrote last week on the group's Facebook page, "but turn up the intensity, election is fast approaching, our country's future is at stake!!!"

Times researcher Caryn Baird contributed to this report. Contact Alex Leary at aleary@tampabay.com. Follow @learyreports.