Jerry Goldman, a Jewish attorney from Philadelphia who represents the families of men and women killed in the September 11, 2001 attacks, never expected to meet with a top Al Qaeda terrorist convicted in connection with that attack, and at the terrorist’s own request.

But that’s what happened when Goldman met Zacarias Moussaoui, known as the “20th hijacker” in the 9/11 attack, on October 20. Now, the outcome of that meeting, along with an unexpected recent court ruling, have revived the prospect that a long languishing court case could reach trial, airing charges that high-ranking officials of the Kingdom of Saudi Arabia helped enable the 2001 terrorist attacks that killed nearly 3,000 people.

“It wasn’t troubling,” Goldman told the Forward, recalling the hours he spent with Moussaoui at the super-max prison in Florence, Colorado, where the convicted terrorist has been sentenced to serve the rest of his life without parole. “Intimidating wouldn’t be the word, nor would scary… My personal impression was — wow, it’s interesting hearing this directly from someone with personal knowledge, directly from the source.”

The firsthand personal knowledge Moussaoui claims to have, which now fills more than 100 pages of court filings, implicates several Saudi princes who were working closely with the U.S. government as active supporters of the Al Qaeda terrorist network in the years leading up to 9/11. Moussaoui was arrested by the FBI on an immigration violation less than a month before 19 Arab hijackers commandeered three commercial planes for use as weapons against their U.S. targets; he first aroused suspicion over the flight training courses he was taking in Eagan, Minnesota. He eventually pleaded guilty to conspiring to kill U.S. citizens as part of the 9/11 attacks. Transcripts of Moussaoui’s testimony to Goldman and three other lawyers were filed with the court hearing Goldman’s case on February 3.

Image by Getty Images Zacarias Moussaoui

Among other things, Moussaoui pointed to former Saudi ambassador to Washington, Prince Bandar Bin Sultan, as an active donor to Bin Laden’s jihad campaign. Bandar was known for his ties to top political circles in Washington and was close to presidents George H.W. Bush and his son George W. Bush. Also on the alleged list of donors to Al Qaeda, which Moussaoui said he prepared at the direct order of Al Qaeda’s leader, Osama Bin Laden, was Prince Turki al-Faisal, who was Saudi intelligence chief at the time. Prince Turki also later served as Saudi Arabia’s envoy to Washington.

Saudi businessman Prince al-Waleed bin Talal, who has been a major investor in Citibank and in Rupert Murdoch’s News Corporation, among other companies, was a third such funder, Moussaoui claimed. He also named Saudi religious leaders as active supporters of Al Qaeda.

In another part of his deposition that could prove embarrassing to the Saudis, Moussaoui recalled meeting with an official from the Saudi embassy in Washington to discuss the possibility of shooting down Air Force One, the presidential airplane, with a personal surface to air missile.

“I mean, you talk about million[s] of dollar[s],” Moussaoui said in broken English, according to his deposition. “You had — for example, they — depending — the — the — the Saudi, okay — the Saudi prince, you know, Abdullah — and he was a new prince at the time, you know — they will give 2, $3 million.”

Goldman, a partner in the New York and Philadelphia law firm Anderson Kill, has no doubt that Moussaoui’s testimony was “100% credible,” though Saudi Arabia contests this vehemently.

If deemed credible by the court, Moussaoui’s deposition could be the most damning piece of evidence to date that the Saudis will have to face. The prospect that they will face it increased greatly in December 2013, when an appeals court unexpectedly reversed its own earlier ruling that had barred the 9/11 families’ suit from going forward in a New York district federal court. According to the current trial schedule, Saudi Arabia has until the end of March to respond to the new evidence presented by plaintiffs, and if the court finds no further reason to accept the Saudi request to dismiss the case, the trial will kick off on April 9.

It is not clear what drove Moussaoui to reach out to the court and testify against the Saudis. Goldman speculated that his long years in prison might have brought the terrorist to reflect on his past and on his comrades. “When somebody sits in jail for a long period of time they get to think of what they did,” he said. Alluding to Bin Laden, who hid out in a large, comfortable compound in Abbottabad, Pakistan until discovered by U.S. intelligence and killed in a flash raid by U.S. Navy Seals, Goldman said, “They see that other people did not go on fighting on the battlefield but were sitting in a nice house down the road from the Pakistan military academy. Those kinds of things motivate someone to talk.”

If successful, the lawsuit could lead to huge judgments against the oil-rich Gulf kingdom to be paid out to families of the victims. The suit could also complicate immensely America’s Middle East policy, which relies heavily on its close partnership with Saudi Arabia, a nation viewed as a stabilizing force in an explosive region of the world.

Moussaoui’s testimony was filed only weeks before another case involving American lawsuits against foreign powers ended in a New York federal courtroom. The Palestinian Authority and the Palestinian Liberation Organization were found liable for terror attacks that killed 10 American citizens during the second intifada and were ordered to pay $655 million in compensation. Taken together, both cases demonstrate an increasing openness of federal courts to taking on lawsuits against foreign governments and entities, acts that at times run counter to the administration foreign policy goals.

Goldman is not the only Jewish attorney representing 9/11 victims in their attempts to win punitive compensation from the Saudi government and Saudi individuals and institutions. Allan Gerson, who was a co-counsel in the original 9/11 lawsuit alongside the late Ronald Motley, has been actively pursuing the case for years, as has Stephen Cozen of the Philadelphia law firm representing some of the plaintiffs.

Religion, however, hardly ever came up in the lengthy proceedings against the Saudis, except for one notable incident Goldman recounted, when he had asked the Muslim World League and the International Islamic Relief Organization, two of the defendants in the case, to produce relevant documents. The Saudi groups responded with an offer to provide the papers only in Mecca, the holy city for Islam where Jews are not welcome. “Obviously, they knew I couldn’t go there,” Goldman said. The judge ruled against their request and forced the Saudis to provide documents in New York. “You don’t use religion as gamesmanship in litigation,” Goldman said. “That’s crass.”

The lawsuit against the Saudis dates back to 2002 and was based on evidence that had suggested members of the royal family and the Saudi banking system had provided support for Al Qaeda. Among these pieces of evidence was information regarding a task force headed in 2000 by then vice president Al Gore, who dispatched administration officials to Riyadh after the Al Qaeda attack in October of that year on the USS Cole. The task force officials demanded that the kingdom put an end to the practice of allowing contributions to Al Qaeda through an Islamic charity system. Similar lawsuits were filed up to 2004, all claiming the Saudis had played an instrumental role in enabling the attacks.

In 2005 the case suffered a major setback when the Saudi government and members of the royal family, who are only part of the giant lawsuit that has named dozens of individuals and entities as terror enablers, successfully argued that they should be protected from legal action because of a policy known as foreign sovereign immunity.

But then in 2013, in a move that surprised even the plaintiffs, the court of appeals overturned its own decision and ruled that the Saudi government and members of its royal family are not immune from prosecution. The reversal came after the 2nd Circuit Court noticed that another panel of the same court allowed a case against the government of Afghanistan to go forward.

In order to avoid inconsistencies, the circuit court reversed its previous decision, citing an “error in law” in the initial decision. The Saudis appealed to the Supreme Court but it refused to take the case.

Experts who had weighed in on the rulings at the time viewed them as a recognition of the extraordinary circumstances involved in the 9/11 case. The decision indicated that in at least some cases, allegations of terror sponsorship and of domestic tort can override the principle of foreign sovereign immunity.

“That was a gift out of the blue,” said Gerson. “It revived the case.”

The Saudi government strongly rejects any claim of its involvement in the terror attacks and has pointed to the 2004 9/11 Commission report, which cleared the Saudi government of conspiring in the attacks or providing funding to enable them. In response to Moussaoui’s testimony, the Saudi embassy in Washington told The New York Times that the convicted terrorist was “a deranged criminal” who was declared mentally incompetent by his own lawyers.

Attorneys representing the families reject this claim and point to a statement by the judge who sent Moussaoui to life in prison, in which she made clear that his judgment is not impaired by a mental condition.

With the court no longer viewing the Saudi government as immune, the kingdom still relies on efforts by the U.S. government to protect its ally. One of the ways the government is shielding the Saudis, claim the plaintiffs, is by refusing to disclose documents that could shed light on the allegations. Among these documents are the papers seized during the 2011 raid on Bin Laden’s compound in Pakistan and 28 pages redacted from the joint congressional committee report investigating the 9/11 attacks.

Image by Getty Images Turki bin-Faisal and Prince Bandar bin Sultan

Activists believe that these 28 pages contain the smoking gun many critics of Saudi Arabia are looking for to prove the kingdom’s involvement in supporting Al Qaeda. Their demand to declassify the section is backed by several members of the committee, including former Florida Sen. Bob Graham, who recently filed an affidavit to the court in support of further inquiry into the Saudi connection to the 9/11 attacks.

It is not clear, however, just how significant these redacted pages will be even if the government agrees to declassify them. Rep. Adam Schiff, a Jewish Democrat from California and a member of the House Permanent Select Committee on Intelligence, is, like Graham, among the few who have been allowed to see the full report. Schiff believes the missing pages are not a game changer. “I have read the 28 pages and the issues raised in those pages were investigated by the 9/11 Commission and found to be unsubstantiated,” Schiff said in a statement provided to the Forward. “I believe that at an appropriate time in the near future they should be declassified — with any redactions necessary to protect intelligence sources and methods — as this would help demystify the issues raised.”

For Goldman, though, the prospect of a trial at last is the main thing. “I was optimistic in March 2004 when I filed the suit,” Goldman said. “The prospects are even stronger today.”

Contact Nathan Guttman at guttman@forward.com or on Twitter @nathanguttman