From the September 26 edition of First 2016 Presidential Debate:
LESTER HOLT (MODERATOR): Mr. Trump, we're talking about the burden that Americans have to pay, yet you have not released your tax returns. And the reason nominees have released their returns for decades is so that voters will know if their potential president owes money to, who he owes it to, and any business conflicts.
Don't Americans have a right to know if there are any conflicts of interest?
DONALD TRUMP: I don't mind releasing. I'm under a routine audit, and it will be released, and as soon as the audit is finished, it will be released.
HOLT: The IRS says an audit of your taxes -- you're perfectly free to release your taxes during an audit. And so the question, does the public's right to know outweigh your personal --
TRUMP: Well, I told you, I will release them as soon as the audit. Look, I've been under audit almost for 15 years.