Much has been said and written about Donald Trump 's refusal to release his tax returns. Tax returns paint a revealing picture of who we are. That's why confidentiality is a central pillar of our tax system. If our government expects taxpayers to share this information with the IRS, we are entitled to ironclad guarantees of confidentiality and privacy — for this reason, our laws provide that wrongful IRS disclosure of our tax-return information is a felony.

But nothing prevents us as taxpayers from choosing to release our tax returns — and those who aspire for the highest public office have done so for decades. And they do so precisely because their returns provide a window (for better and worse) into who they are. Those who say Trump should release his tax returns claim we are entitled to view this portrait of the man who aspires to lead our country.

Trump has promised to release his returns when his audit ends, but claims he is under continuous audit by the IRS and that releasing his returns (including returns for years that are now closed) could have an adverse impact on current and future IRS examinations. As a former IRS commissioner and practicing tax lawyer, I understand it may be inconvenient for Trump to release his tax returns but we all know — and the IRS has confirmed — that nothing prevents any of us from releasing our tax returns any time we want. And by the way, for those who listen carefully, Trump's promise means he will never release his tax returns. Trump's advisors also have substantial control over when his current examination will conclude.

As a citizen and voter, I want to take a look because I will learn something important about this man who would be president. Inevitably, his refusal to release his returns raises a question: What is Trump hiding? The additional audit hassle is nothing compared to the extraordinary burdens he would carry as president. It's a small price of admission to the Oval Office. The sooner he releases his entire returns, the better.

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Be that as it may, however, Trump is so far not willing to take that step. That's his decision, and voters will form whatever judgments they choose to form.

There is, however, a first step that Trump has no excuse for not taking. He can and should immediately release the first two pages of his Form 1040, along with his Schedule A, for the past 20 years. This would tell us how much he makes, how much he pays in taxes, and how much he contributes to charity.

Releasing this information would have no impact on any pending or future IRS audit of Trump. Zero. None. It is a risk-free first step with no downside. While painting a far from complete portrait, it would answer a few of the questions that Trump himself has raised during the campaign: He claims that he makes a lot of money; he claims that he makes significant charitable contributions; and he claims that he reduces his tax liability as far as current law allows.

The first two pages of his enormous tax returns, along with his Schedule A, will shed important light on these claims. The first two pages plus the Schedule A of the Clintons' 2015 tax return tell us they made $10.6 million; that they made charitable contributions of $1.0 million; and that they paid federal taxes of $3.6 million, for an effective tax rate of 34 percent. We have that same information about the Clintons for the past 20 years. The first two pages of Trump's tax returns, together with his Schedule A, would provide us with the same information for him. He can and should share that information with no audit risk whatsoever.

This would be a beneficial first step. His full return, as is the case with any individual having complex business affairs, would provide further important information, helping to paint a more complete portrait of Trump. For example, it could provide insight into Trump's record in business, such as more information about his important sources of income (real estate, domestic and off-shore investments) and the tax impact of debt forgiven in his bankruptcies.

A couple of my own disclosures: I had the honor of being appointed IRS chief counsel by President Reagan, and being appointed IRS commissioner and then Assistant Secretary for Tax Policy at the United States Treasury by President George H.W. Bush. This year, I will be voting for Hillary Clinton . I am confident she will keep us safe and that she could and would work with Republicans in Congress to lead our country to a better future for all Americans.

Commentary by Fred Goldberg, who was appointed IRS chief counsel by President Ronald Reagan and as IRS commissioner and as Assistant Treasury Secretary for tax policy by President George H.W. Bush. He is currently a tax attorney in private practice.

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