Hillary claimed that The Donald managed to pay zip for taxes a few years ago. The Donald did not deny it, in fact he said "That's being smart". Which it is. As CEO of his company, it is Donald's duty to maximize returns to his stakeholders, not Uncle Sam.
The real question is, what gaping loopholes did a billionaire use to skate on paying taxes? Certainly any moderator with an IQ above room temperature ought to ask that question next time. Another good question, what reforms to the tax law will you make to prevent billionaires from skating on taxes?
Although Hillary promised a tax hike, and The Donald promised a tax cut, both of them could have been more forthcoming about what they want to do. Is Trump talking about just the corporate tax, or personal income tax as well?
Hillary's promise of tax hikes indicate her overall cluelessness. The economy is still in the hole dug back in 08. GNP growth is a measly 1.7%. Hiking taxes, taking money away from those who earn it, and giving it to bureaucrats, pushes the economy further underwater.