One of the biggest mysteries hovering over the 2016 presidential campaign has been the tax returns belonging to Donald Trump. While parts of Trump's financial history have been leaked, larger questions still remain.

Tax trouble

For the first time in 40 years, a presidential candidate is set to keep his tax returns hidden from the public. Trump cites a current audit by the Internal Revenue Service (IRS) for why he hasn't released his returns, but government officials have confirmed that there is no legal reason he can't make them public. During Sunday night's debate against Hillary Clinton, Trump was pressed on his tax returns, where he decided to bring up billionaire Warren Buffett.

As reported by Vox on October 10, Buffett has responded.

Buffett claimed that while "Trump says he knows more about taxes than any other human. He has not seen my income tax returns." Buffett said he was more than happy to show Trump "the facts," which include his 2015 tax returns detailing an "adjusted gross income of $11,563,931." Buffet took a total deduction of $5,477,694, including "allowable charity contributions" of over $3 million. Buffett went on to show that he paid more $2 million in federal taxes for that year.

Going back further, Buffett claims he has paid federal income taxes for the last 72 years, dating back to 1944 when he was only 13-years-old, though he only owed $7 to the government in that year.

Concluding his statement, Buffett pointed out that he has been audited by the IRS on several occasions, and he's not had an issue releasing his taxes because of it, conflicting with the excuse made by Trump.

Moving forward

Trump's tax issues took a major hit last weekend when The New York Times obtained and released portion's of his 1995 tax returns, showing that there was a possibility he hasn't paid taxes for the last 18 years.

While his tax returns have been a major issue, Trump is currently dealing with several scandals that threaten to derail his campaign, including a leaked audio tape where the former host of "The Apprentice" is caught admitting he tried to have sex with a married woman, and his desire to grab women by their private parts.