The verdict touched off a tearful celebration among Barrack and his supporters, who took group photos in the courtroom. “I’m so thankful for this system,” Barrack said, expressing appreciation for the jury.

One of Barrack’s assistants, Matthew Grimes, was also acquitted.

Barrack’s acquittal was the latest setback for the Justice Department, which in recent years has stepped up enforcement of laws governing foreign lobbying.

Last month, a judge dismissed a lawsuit that sought to force casino magnate Steve Wynn to register as a foreign agent because of his alleged lobbying at the behest of the Chinese government during the Trump administration.

In 2019, lawyer Greg Craig, a Democrat, was acquitted of making a false statement to the Justice Department about work he did for Ukraine’s government.

Trump also pardoned two allies who had been convicted of secretly lobbying the US for foreign interests: former campaign manager Paul Manafort and a top fundraiser, Elliott Broidy.

In closing arguments on Tuesday, Assistant US Attorney Ryan Harris told jurors that Barrack schemed to become the “eyes, ears and the voice” for the Emirates as part of a criminal conspiracy to manipulate Trump’s foreign policy.

At the same time, he leveraged his backchannel connections to get the UAE to funnel tens of millions of dollars into an office building he was developing and into one of his investment funds, Harris added.

The prosecutor pointed to what he characterised as a steady steam of shady texts and other communications that showed that Barrack was under the direction and control of Rashid al Malik, a business-person from the UAE who acted as a conduit to the rulers of the oil-rich Persian Gulf state.

Barrack “marketed himself as politically connected. Someone who could open doors for the UAE. Someone who could offer access to Donald Trump … He was going to be their man on the inside”, Harris said. Al Malik asked Barrack “to do things for the UAE again and again”, he said.

Defence lawyer Randall Jackson said Barrack made no attempt to conceal his relationships with Al Malik, someone in a network of business connections he had cultivated throughout the Middle East.

He also said it “makes no sense” that his client would try to infiltrate the Trump campaign on the behalf of the UAE at a time when Trump’s chances of winning the presidency were considered a long shot.

“He was involved in the campaign because he’s loyal to his friends – maybe to a fault,” the lawyer said.

Last week, Barrack testified that “dozens” of people asked him for help in getting pardons from the former president. He also said he never sought a pardon for himself, even after he learned he was under investigation. Asked why, he responded, “I never did anything wrong.”

Barrack, an Arabic speaker of Lebanese descent, also described efforts to arrange for Trump to meet with UAE national security adviser Sheikh Tahnoun bin Zayed Al Nahyan and other officials from more moderate governments in an effort to persuade Trump to tone down his anti-Muslim rhetoric.

“I was trying to get common ground, to try to get him to step back from what he didn’t believe,” he said.

The defence called former Treasury Secretary Steven Mnuchin to testify there was nothing suspicious about his interactions with Barrack over Trump’s stance on UAE relations.

Mnuchin described Barrack as a friend who was among hundreds of businesspeople offering him “thoughts and advice” while he served in the cabinet. In those discussions, “I would never share anything … that I thought was confidential,” he testified.

Before being indicted, Barrack drew attention by raising US$107 million for the former president’s inaugural celebration following the 2016 election. The event was scrutinised both for its lavish spending and for attracting foreign officials and businesspeople looking to lobby the new administration.