In 2009 the US Justice Department issued a fine of $780 million against Swiss banking giant UBS. The financial institution was found guilty in a massive fraud investigation after Birkenfeld came forward with insider knowledge of the bank’s role in tax evasion.
Despite his high-profile role in financial whistleblowing, Birkenfeld has strong doubts about the Panama Papers released earlier this month.
"The CIA, I’m sure, is behind this, in my opinion," he said during an interview with CNBC.
"The very fact that we see all these names surface that are the direct quote-unquote enemies of the United States – Russia, China, Pakistan, Argentina – and we don’t see one US name. Why is that?" he added.
"Quite frankly, my feeling is that this is certainly an intelligence agency operation."
The largest leak of its kind in history, the Panama Papers refers to over 11.5 million documents taken from law firm Mossack Fonseca.
"If you’ve got NSA and CIA spying on foreign governments they can certainly get into a law firm like this," Birkenfeld said.
"But they selectively bring the information to the public domain that doesn’t hurt the US in any shape or form. That’s wrong. And there’s something seriously sinister here behind this."
While the documents also revealed the financial improprieties of Icelandic Prime Minister Sigmundur David Gunnlaugsson and British Prime Minister David Cameron, Birkenfeld ascribes that to "collateral damage."
Many question why the Panama Papers seem suspiciously absent of American names and a number of theories have been raised. Some point out that the United States, itself, is a fairly lucrative tax haven, and so Americans have less reason to place money overseas.
Others have pointed the finger at American businessman George Soros.
"WikiLeaks told you the Panama Papers were provided by the United States government, George Soros’ various NGOs, and a host of western journalists," political analyst Phil Butler wrote for New Eastern Outlook.
"Today the proof is irrefutable. A vast network has been established in the last few decades to not only control news, but to influence even the laws under which society operates."