Gordon said he has always paid his taxes in full and disclosed his account at UBS to the IRS each year he held it. Unlike some other clients who had accounts at UBS, Gordon said he wasn't trying to avoid taxes. Instead, he opened his account out of fear of more attacks in the U.S. after 9/11. Joan Papadakis, CEO of Gordon's family office, called it his "Armageddon account."
"The only reason we went offshore was because of 9/11," Gordon said. "The funds that were in Switzerland were just my personal funds. I got a little nervous about the way things were going."
Gordon declined to say how much money was in his UBS account, or what the source of the funds was. But he said that after Birkenfeld's disclosures about secret accounts in Switzerland he decided to bring his money back to the United States. "I was a client of the bank," he said. "We have always been and always will be good taxpayers."
Gordon crossed paths with the Swiss bank whistleblower Birkenfeld while a client of UBS, he said—attending an event at the Miami Zoo with the banker.
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That was a year or so before one of Gordon's other lines of business made the news.
In 2005, The New York Times reported that a private aviation company owned by Gordon called Presidential Aviation, was involved in an alleged rendition flight of an apparent terrorism suspect. The suspect, a Canadian engineer named Maher Arar, said he was detained by U.S. authorities in New York and then secretly sent to Syria, where he was "brutally beaten with a metal cable." The Times reported at the time that the Justice Department said Arar had been deported based on "secret information that he was a member of Al Qaeda." Arar denied he was a member of the group. He was later exonerated by Canada.
According to the Times, a plane matching the description Arar gave was owned by a company that was in turn owned by Gordon, who owned Presidential Aviation at the time.
In a telephone call with CNBC, Gordon confirmed that his company was involved in flying detainees for the U.S. government. "One of our clients was the government," Gordon said. "Occasionally they would ask us to do trips, and we would do the trips. They would ask us to transport someone from one place to another. It wasn't always overseas, some of the flights were within the United States."
Asked which agency of the U.S. government paid for the flights, Gordon said he does not remember.
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"I owned the company and I invested money in the company," Gordon said. "But I was more interested in flying airplanes." Asked for more detail, Gordon demurred. "We had a couple flights," he said. "It was not a regular everyday thing. I don't know who it was or any of the circumstances surrounding it."
Gordon also said that the U.S. government did not send funds to his Swiss account but paid Presidential Aviation though its corporate bank account.
Papadakis, who oversees Gordon's finances, explained that the businessman paid all of his taxes on the Swiss account even though, she said, the Swiss did not make it easy to declare an account to the U.S. government.
"It was actually difficult to report," she said. "I had to request statements from UBS every year. You had to specifically request them. And I had to wait sometimes two or three months. When I got them we included them each and every year."
UBS said it has put these kinds of issues behind it. "UBS today is a different firm, with a different strategic focus and senior management team," a bank spokeswoman said.