As the days tick by and Mitt Romney remains the only Presidential candidate in recent history (including his father) who refuses to release all relevant tax returns, the speculation is growing as to what Romney is hiding.

Some people think that Romney might have cheated on his taxes in some way, despite his assertion that he has paid every dime that he owed.

Some people think that Romney might have abused offshore accounts, shell companies, and other sophisticated tricks.

Some people think that Romney might have deducted some of the $35+ million he spent on his own Presidential campaign in 2008 as a business expense, something that would almost certainly violate rules (campaign donations aren't deductible).

And so on.

Romney boosters are quick to dismiss all this speculation as left-wing propaganda, but for anyone who isn't just "rooting" for a particular political team, this is ridiculous. Again, Romney remains the only recent candidate who refuses to release his returns (Romney's opponent, Barack Obama, in contrast, has released 11 years of them). Obviously, the Democrats are going to do everything they can to try to make hay out of this issue, but it is an issue that should have hay made out of it. The press absolutely should keep demanding that Romney release his returns--because America deserves to see them.

Romney is running for President of the United States, not president of the local school board. Given that his primary policy plank is his business and financial expertise, Americans deserve to know more about that expertise. Specifically, Americans deserve to know what they have known about every other Presidential candidate in recent history--namely, what's in their tax returns.

For what it's worth, my guess is that what Romney is hiding in his tax returns is not something that is clearly illegal or dishonest, but, simply the following reality:

Romney has made hundreds of millions of dollars

He has paid very little of that (on a percentage basis) in taxes

He has made hundreds of millions of dollars in part because he has structured most of his income in ways that enable him to pay the least amount of taxes possible

This "structuring" of income has likely taken full advantage of things like the ludicrous "carried interest" tax exemption that allows private-equity investors to pay capital gains taxes on income that is actually fees [This tax treatment is one of the most outrageous and unfair elements in the entire tax code. There is no logical basis for it, and it benefits only the richest people in the country.]

This "structuring" has also likely taken advantage of offshore accounts, the contribution of hard-to-value securities at low valuations to Romney's IRA (whereupon they exploded in value), and other sophisticated tools. These tools are, theoretically, available to anyone, but, in practice, are available only to those with tens of thousands of dollars to spend every year on tax-and-estate planning.

This structuring, which (let's be honest) is done primarily to avoid paying taxes, will look bad to most Americans, who will know instinctively that it's done to avoid paying taxes and that it's not something they will ever be able to afford to do--and, therefore, will seem unfair.

In short, by not releasing his returns, I think Romney is trying to avoid calling more attention to the fact that he is a card-carrying member of the 0.01%, a group of Americans who deserve to be proud of their success but who are also understandably viewed with suspicion and frustration by most other Americans right now, especially when they argue that they're still paying too much in taxes.

That's what I think Romney's hiding.

And I can understand why some of his advisors are telling him he can just hold on and weather the storm--because they know it won't help him to have those details out there.

But it will help the country.

It will help us assess Mitt Romney as a Presidential candidate--and a person.

It will also shed more light on just how much some of our tax laws favor the super-rich.

If those tax laws are reasonable, they should withstand such scrutiny--and Romney should proudly stand behind him.

And if those laws are unreasonable or unfair (which the "carried interest" exemption absolutely is), then maybe Romney's tax returns will help rally support to get them changed.

Either way, America deserves to see them. And what's in them will come out eventually, whether or not Romney chooses to release them. The only question is "when?"

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