The experts have offered an array of arcane theories about the mechanisms Trump might have used to avoid paying taxes. A leading theory is that Trump was able to “double dip” by using the tax code to avoid paying taxes on huge loans that he did not have to pay back and at the same time deduct massive losses from businesses that were financed by the loans.

No one knows for sure what provisions his accountants used because Trump — unlike every other major presidential nominee over the last four decades — has refused to release his tax returns.

The controversy has dominated the presidential campaign in recent days. After Clinton accused Trump of taking unfair advantage of the tax code, Trump said at a campaign rally on Tuesday, “She complains about how I’ve used tax laws of this country to my benefit. Then I ask a simple question: Why didn’t she ever try to change those laws so I couldn’t use them?”

She did. After the Supreme Court in an 8-to-1 vote upheld the “double dip” loophole in 2001, Congress the next year voted to disallow it. Then-Sen. Clinton was among those who voted it down.