3 Reasons why USA care about politicians' taxes

1. Conflicts of interest: Almost every candidate who runs for public office is fairly wealthy. (Even the candidates who have the government pay their salary, like Bernie Sanders and Joe Biden, make far more money than the average American.) Because of that wealth, how they made their money (we'll get to heart in a second) can tell you whether they have potential conflicts of interest — who they made that money from. Trump's business interests all over the world could become entangled with presidential politics. Just look at his response to Brexit — that the dropping euro could be good for tourism to places like his Scottish golf course. For the Clintons, the Clinton foundation could also raise the issue of conflicts of interest as it raises gobs of money from foreign entities. Would some of those governments expect special treatment from a second President Clinton? A look at recently released emails from her time at the State Department — and what aides did for big Clinton foundation donors — gives people reason to question.

2. Do they have heart?
Tax returns tell us how much candidates give to charity. The Clintons, as noted above, gave between 8 and 15 percent — or about $15 million total — during that eight-year period. Most of that went through the Clinton Family Foundation, as The Atlantic reported. They also contributed to the Nelson Mandela Foundation, First United Methodist Church and the Humana Challenge golf tournament. People could have questions about why so much of their money went to their own foundation — and whether that's really in the spirit of giving. For Trump, on the other hand, it took a Washington Post investigation to unearth that he hadn't given $1 million to veterans' charities, as he had promised after a fundraiser he held earlier this year (an event he held in competition with a debate he decided not to attend because he was upset that Fox News' Megyn Kelly was moderating). Trump eventually laid out how much was raised and allocated in a testy news conference. So is criticism of Trump unfair? Is he really quietly a very charitable person — or not? Tax returns would reveal that.

3. Are they like us?
Again, these candidates are much wealthier than the average American. Median household income in this country is $53,482, according to thecensus. The Clintons made $28 million in 2014 (mostly from speeches). They also live in a posh New York suburb, Chappaqua, where they bought their home for $1.7 million in 1999 just before leaving the White House. (In 2016 money, that appreciates to about $2.5 million.) The average home price in the U.S. in June 2016 was $358,000 (median home price was $307,000). Trump, of course, makes it a point to say he's "really rich," claiming he's worth $9 billion. Trump's net worth is something of a mystery. He says it fluctuates even based on his own "feelings." The Washington Post reported this week on a 2007 deposition that caught Trump in repeated lies and exaggerations when it came to his wealth and earnings. His tax returns would certainly clarify whether he is as rich as he says. There's also the business of tax rates. The Clintons have paid a fairly high tax rate over the years. Trump, on the other hand, has boasted that, "I fight very hard to pay as little tax as possible" and called his tax rate "none of your business." But when a candidate fights hard to pay less in taxes than most people, especially when he is uber-rich, that can be a political problem. That was certainly the case in 2012, when the Obama campaign and its outside group allies were able to paint Mitt Romney as someone who got away with paying less in taxes. (Romney paid an effective tax rate of 14 percentbecause so much of his income came from dividends and capital gains.)

From the NPR