The New York Times released a late-night report suggesting that Donald Trump may have paid zero federal income taxes for 18 years. The Times obtained a copy of his 1995 income tax returns, in which he reported a $916 million business loss. According to tax experts, he could spread out the deduction over the next 18 years, and it would be large enough to wipe out $50 million of taxable income for each of those years. So, with that deduction alone, if Trump's taxable income did not exceed $50 million each year, he would have owed no tax. And it would be perfectly legal.
What is not known is whether Trump did have more than $50 million taxable income in any of those years; and, given his smart tax lawyers, they probably manipulated the loopholes so that he didn't. So far, Trump has not denied that this is true, although he did find time to charge that the 1995 document was obtained illegally and that the Times is operating as an extension of the Clinton campaign.