With all the worry about Russian influence over U.S. elections it’s easy to overlook the many foreign interests working to impact U.S. policy every day–through paid lobbying.

American lobbyists have made billions working for foreign entities. Who’s paying whom for what is subject to federal disclosure laws. But the system may not always work as intended. In the latest episode of “Full Measure” we investigated a case in point: some U.S. military vets who claim they were duped into lobbying for the wrong side.

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This twisted tale of Washington, D.C., lobbying begins in an unlikely place. With a rock band from Utah.

That’s Tim Cord singing … his brother on lead guitar … both Iraq war vets.

Tim Cord, U.S. Military veteran: My brother and I were in a rock band called American Hitmen … so we’ve kind of made a name for ourselves in the music scene as veterans.

They hoped to play at President Donald Trump’s inauguration. But when that gig didn’t come through, a political contact they’d met on the road offered what sounded like a decent consolation prize.

Cord: He just said it’s going to be an all-expensive, all-expense paid trip for four days basically to see how D.C. works is basically how they worded it.

Shortly before the January trip, one organizer sent an email mentioning a political angle: a new law called “JASTA”—the Justice Against Sponsors of Terrorism Act.

It allows families of 9/11 victims to sue Saudi Arabia for any alleged ties to the Islamic extremist terrorist attacks.

Cord: We thought we were going to just go hang out in … D.C. and basically see politicians, see this, meet with this group of vets that were there to talk about the JASTA bill.

The trip to the Capitol began with open bar at a luxurious hotel with retired generals and Purple Heart recipients.

Folders were handed out claiming JASTA was disastrous for veterans. Then came an odd announcement, Cord says, from organizer Jason Johns—a veterans’ advocate.

Cord: Jason Johns stood up and he said, ‘Thank you all so much for coming … we want to protect the veterans and I know there’s a lot of rumors going around but we can assure you there’s no Saudi money behind this.’ … I don’t think any of us, at least at my table, had even thought about the Saudis. It was just kind of a weird statement to make opening night.

He says things got stranger the next day when they were split into groups to visit Senate offices to promote supposed improvements to JASTA.

Cord: Every time we would go into one of their offices, they would say, ‘Who are you here on behalf of?’ And whoever was our group leader would say, like flat out, “Oh no, we’re just a group of concerned vets volunteering our time.

That night, he says, his suspicions were confirmed by a drunk confession from an organizer.

Cord: I said, ‘So, by the way, who’s paying for all of this?’ And he’s like, ‘Dude, it’s the Kingdom.’ And I said, ‘The Kingdom of Saudi Arabia?’ And he’s like, ‘Yeah, man.’ So this was unraveling into something that I wanted no part of. We joined the Marine Corps after 9/11. I mean 15 of the 19 hijackers on 9/11 were Saudis, so I don’t want anything to do with the Saudi Arabian Kingdom or their money.

Cord says he shared the news with his group and confronted the contact who first invited him on the trip.

Cord: He goes, ‘Well, welcome to politics, Tim. It’s either Obama and the Iranians or the Republicans and the Saudis. Welcome to Washington.’ It came to the realization that my brother and I were sitting there eating catered dinner on the Saudi dime in an attempt to shoot down the 9/11 victims’ families lawsuit against the Saudi Arabian Kingdom. It was probably one of the worst feelings I’ve had in my life.

Lydia Dennett, Project on Government Oversight: That seemed to be a tactic from recruiting veterans to talk about the negative implications of this law and to do so in a way that sort of obscured Saudi Arabian involvement in it.

Lydia Dennett is an investigator with the nonprofit watchdog Project on Government Oversight … which has been tracking Saudi lobbying efforts.

Dennett: Because it was done through this lobbying firm, the veterans themselves, and the public, may not have known that these were talking points and issues that were coming from the Saudi Arabian government. That sort of undermines the entire transparency and intent of the Foreign Agents Registration Act.

The Foreign Agents Registration Act (FARA) of 1938 requires lobbyists for foreign interests to register and file reports.

Dennett: By the end of 2016, the Saudi Arabian government had 22 different lobbying firms to promote their interests in the U.S., of which were added in the fall of 2016 alone. Right around the time that JASTA was or the 9-11 bill was introduced, going through debate hearings, and then ultimately passed.

For example, a company called Qorvis has been on the Saudi payroll since two months after the 9/11 attacks. The original contract disclosed $200,000 a month in payments—$2.4 million a year.

Sharyl Attkisson: What do you sense the Saudis were trying to do when it comes to that bill?

Dennett: They were trying to get their message out there, which was that it was a dangerous bill that would set a dangerous precedent across the world.

That messaging flooded the media … that JASTA would cause foreign countries to retaliate and sue our military personnel in foreign courts. Which is the argument President Barack Obama made in September when he vetoed the bill.

Former President Barack Obama: That concern that I have has nothing to do with Saudi Arabia per se or my sympathy for 9/11 families. It has to do with me not wanting a situation in which we’re suddenly exposed to liabilities from all the work that we’re doing around the world.

But Congress overrode the veto. So Qorvis sprang into action, hiring none other than the man who would go on to help organize the Washington, D.C., trip: Jason Johns. It turns out he’s not just a veterans’ advocate. He owns a lobby firm of his own and officially registered to lobby elected officials on behalf of Saudi Arabia.

Cord: We found out afterward, that Jason Johns was a registered Saudi agent, and he made $100,000, it’s on public record that he was paid $100,000 by the Kingdom and registered as a Saudi agent. That’s the guy that said in the beginning, ‘There’s a lot of rumors that this is Saudi money and it’s not, I can assure you.’

By email, Johns told us that vets with “ulterior motives” are issuing “mistruths and false allegations.” He declined our request for a one-on-one interview and insisted we interview “at least three other” unnamed vets he would arrange in a group setting with him. We explained that under news policies, we can’t agree to terms, such who we must interview. Johns added we shouldn’t focus on “a few veterans feeling they were ‘duped’ but … why hundreds … volunteered to go to D.C. and speak about why amending JASTA is so vital to them, our currently serving military, and our national security.”

Qorvis declined our interview requests but has previously denied deceiving veterans, said it reports disclosures accurately, and it’s “hard to believe anyone would feel they didn’t know why they were in Washington.

Attkisson: Saudi Arabia might say everything we did was perfectly legal. U.S. law allows them to hire people in this country and lobby for their interests. What did they do wrong?

Dennett: In any written materials distributed, if there were emails sent to these veterans or their veteran groups, they’re required to say very clearly in there, ‘This is information, we’re being paid to distribute this information by the Kingdom of Saudi Arabia and more information is available at the Department of Justice.’ If the emails or any documents did not include that statement, then that’s a violation of the law.

In fact, an examination of some emails trip organizers allegedly sent to vets made no mention of Saudi lobbying. This one billed the D.C. trip as “basically like a 5-star vacation,” noting, “you don’t have to know anything about JASTA.”

Attkisson: Why should ordinary Americans care about this?

Dennett: The issues that these foreign countries are lobbying on can be everything from foreign aid to arms deals, … appropriated funds, which come from taxpayer dollars. So, the public deserves to know exactly how the policy is being made.

Cord says, in the end, one promise of his trip was fulfilled. He did learn a lot about how Washington works.

Cord: It was the worst feeling ever because there’s nothing I can do about it. My name will forever be on a ledger, my brother’s name will forever be on a ledger saying that we were wined and dined by the Saudis. And it’s not a good feeling. It sucks.