Saudi Arabia, a key U.S. ally and home of 15 of the 19 Sept. 11 hijackers, was funding an expensive campaign to oppose a law passed by Congress that allows victims’ families to sue any foreign country found to support a terrorist attack that kills U.S. citizens on American soil, the Associated Press reports.

The campaign, carried out by a number of American public relations firms and lobbying  groups, involved paying U.S. veterans to visit Capitol Hill and warn lawmakers about the potential unintended consequences of the bill. Many of the veterans who took those trips were unaware that they were being funded by the Saudi government.

“It was very evident that they weren’t forthcoming; they were telling us the whole truth,” David Casler, a former Marine who was recruited into the campaign, told the AP. “They flat-out lied to us on the first day with the statement: ‘This is not paid for by the Saudi Arabian government.’”

Congress passed the law, the Justice Against Sponsors of Terrorism Act, or JASTA, in September, overriding a veto by President Barack Obama. The bill didn’t mention any specific countries, but it was obviously aimed at Saudi Arabia. While the 9/11 Commission’s final report found no evidence that the Saudi government or officials funded al-Qaeda, it concluded that the terror group found “fertile fundraising ground in Saudi Arabia.”   

Osama Bin Laden, the mastermind behind the Sept. 11 attacks, was born and raised in Saudi Arabia. He was expelled from the kingdom in 1991, a few years after founding al Qaeda. However, Zacarias Moussaoui, the so-called “20th hijacker,” who is currently serving a life sentence in Colorado for his connections to al Qaeda, testified in 2014 that Saudi leaders had supported the terrorist group with money and coordination up until the 2001 attacks. Moussaoui’s testimony fueled rumors of Saudi involvement in 9/11 that have swirled since the attacks.     

The Saudi Foreign Ministry responded to the passing of JASTA by saying it hoped “wisdom will prevail and that Congress will take the necessary steps to correct this legislation in order to avoid serious unintended consequences that may ensue.” Part of the effort to spread that “wisdom” was carried out by veterans deployed to Washington by a network of lobbying firms.  

Soon after JASTA was passed, a lobbying and public relations firm that represents Saudi Arabia called Qorvis MSLGroup hired 70 subcontractors to alert lawmakers and the general public to “potential legal liabilities arising for U.S. military, intelligence, and diplomatic personnel.”

The chief lobbyist for the Saudi Embassy in Washington told the AP that it had funded the campaign, but that it had encouraged its subcontractors to be as transparent with that fact as possible. Under federal law, anyone working on behalf of a foreign government must register with the U.S. government before beginning work. However, one of the organizations spearheading the campaign, a California-based firm called Capitol Media Group, did not register until three months after it began sending “groups of 25-35” veterans to Capitol Hill.   

Veterans recruited into the campaign had their flights and accommodations — including stays at the Trump International Hotel in Washington —  paid for with Saudi money distributed by the subcontractors, according to Justice Department filings examined by the AP.  The veterans were encouraged to wear their medals when meeting with Congress.

In an interview with the AP, Chuck Tucker, a retired U.S. Air Force major general who took part in the lobbying, said he knew all along that the campaign was being funded by the Saudis.

“You stay with your wingman. We have allies. They’re not perfect, we’re not perfect,” he said. “It’s not like it was blood money. We’re taking money from somebody who is our friend and ally helping us around the world.”