Donald Trump has so far refused to disclose his tax returns because he is "hiding something" and may not have paid tax on his business holdings in the past, Hillary Clinton claimed in last night's first presidential television debate.
The Democratic candidate began by reminding viewers that "for 40 years everyone running for president has released their tax returns", before questionning the logic behind why her Republican rival had declined to do so.
"It must be something really important, even terrible, that he's trying to hide," Mrs Clinton said.
"This is something the American people deserve to see and I have no reason to believe that he's ever going to release his tax returns because there's something he's hiding.
"And we'll keep guessing at what it might be that he's hiding. Who does he owe money to? He owes you the answers to that, and he should provide them."
Mr Trump's excuse for the past seven months has been to claim that the Internal Revenue Service (IRS) is in the process of auditing his accounts.
But Mrs Clinton countered that claim by saying: "The IRS has made clear there is no prohibition on releasing it when you're under audit. So you've got to ask yourself, why won't he release his tax returns?
"I think there may be a couple of reasons. First, maybe he's not as rich as he says he is.
“Second, maybe he's not as charitable as he claims to be. Third, we don't know all of his business dealings but we have been told, through investigative reporting, that he owes about $650 million to Wall Street and foreign banks.
“Or maybe he doesn't want the American people, all of you watching tonight, to know that he's paid nothing in federal taxes because the only years that anybody has ever seen were a couple of years when had he to turn them over to state authorities when he was trying to get a casino license and they showed he didn't pay any federal income tax…”
Mr Trump meanwhile said "That makes me smart" and resolutely defended his decision not to release the details, before claiming he would do so if Mrs Clinton "releases her 33,000 emails that have been deleted".
Two weeks ago, Mr Trump's son Donald Jr. said the release of his father's tax returns would "detract from his main message".
During a heated exchange, Mrs Clinton accused Mr Trump of racism, deceit and of failing to pay his employees for their work on his many properties.
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