While not required to release their tax returns for the prior year, all but one major party nominee since 1976 have done so. (Gerald R. Ford released only a summary.)
So far, neither of the 2016 presidential nominees has adhered to this tradition, though Hillary Clinton has released eight years of returns through 2014. Brian Fallon, a spokesman for her campaign, said that Mrs. Clinton would release her 2015 return “soon.”
Donald J. Trump has cited Internal Revenue Service audits as a reason for not releasing his returns.
The Audit QuestionThe I.R.S. says Mr. Trump is free to release his tax returns despite the audit. There is some precedent: President Richard M. Nixon released his tax returns while he was being audited, though not until after he was re-elected in 1972.
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Donald J. Trump ✔@realDonaldTrumpSigning my tax return....
1:13 PM - 15 Oct 2015
Joseph J. Thorndike, director of the Tax History Project at the nonpartisan Tax Analysts, says that the complexity of Mr. Trump’s returns is exactly why they should be released. “Unless they are made public, Americans are faced with voting for or against someone whose business interests are almost entirely opaque.”
Why It MattersMr. Trump filed financial disclosure forms in May, which is required of presidential candidates. However, experts say tax returns provide more precise data on sources of income, effective tax rates and charitable donations.
Mitt Romney’s returns revealed that he paid an effective tax rate of 14 percent on his income, which came mostly from investments — far lower than the top 35 percent rate for wages and salaries. He was also criticized for holding money in offshore accounts.
“Releasing your tax returns provides voters with a fuller picture into your background, experience, business interests and insight into potential conflicts of interest,” Karen Hobert Flynn of the public interest group Common Cause wrote in a letter to Mr. Trump urging him to release his returns.
Mr. Trump’s ResponseIt has evolved since he declared his candidacy in June 2015.
Aug. 2, 2015, “Face the Nation”
“We’ll see what I’m going to do with tax returns. I have no major problem with it, but I may tie them to a release of Hillary’s emails.”
Feb. 25, 2016, CNN
“My returns are extremely complex, and I’ll make a determination at the right time.”
May 11, 2016, Associated Press interview
“There’s nothing to learn from them.”
May 12, 2016, “Good Morning America”
“When the audit ends, I’m going to present them. That should be before the election. I hope it’s before the election.”
July 28, 2016, Fox News
“I remember with Mitt Romney four years ago, everybody wanted his, and his is a peanut compared to mine. It’s like a peanut. It’s very small. Not nearly as big a document. I mean, mine, you saw the picture where it’s two or three feet high.”