In 1952, vice presidential candidate Richard Nixon gave his famous “Checkers Speech,” wherein he defended himself against accusations of taking money from his supporters for “personal use.”

As a part of the speech, Nixon gave his financial history. He said that he never accepted any sort of bribery, and he never kept a gift other than a cocker spaniel, whom his family named Checkers (who could blame him for keeping a cute dog?).

It was smooth political maneuvering, and it certainly paid off. The move put his opponents on the spot, and thus began the tradition of candidates disclosing their financial history.

According to a CNN article “Presidential candidates have a long history of releasing tax returns,” Nixon’s opponents ended up releasing their financial information as well and that became the new normal.

While Nixon didn’t go so far as to release his tax returns until after he was in office, the expectation since the 1970s has been that candidates do so in advance. And this has mostly been the case for decades — that is, until one Mr. Donald J. Trump came along.

Why would The Donald refrain from participating in this proud tradition?

But first, what are tax returns? According to the Collins English Dictionary, a tax return is, “a declaration of personal income made annually to the tax authorities and used as a basis for assessing an individual’s liability for taxation.”

Why is it important for the public to know this?

When a candidate reveals his or her tax returns, it builds trust. Americans really like the idea of their leaders being transparent.

Donald Trump asserts that he’s made a truly remarkable amount of money; this is meant to lend credibility to him as someone who could manage the economy.

Could it be that Trump is simply not as rich as he says? Or maybe the returns would reveal that many of his business endeavors have gone badly wrong. There is also the issue of how charitable he might or might not be.

Another possible reason for Trump’s refusal could be foreign investors. According to a CBS News article titled “Two wealthy donors offer reward for Donald Trump’s tax returns,” possible dealings with Russia or China would be revealed by filing his returns.

Trump maintains that he does not have investors in Russia, but his admiration for the undemocratic state and its dictator, Vladimir Putin, raises some concern.

The BBC article “Donald Trump ‘Honored’ by Vladimir Putin’s Compliments” demonstrates the sort of respect Trump has shown again and again for Putin. He said he thought he would get along with the dictator and considers him “highly respected within his own country and beyond.” Indeed, Trump’s permissive outlook toward Russia has been fairly consistent for months now.

The question remains: what is Trump waiting for? I have to say, it certainly looks strange that his opponent, who he has dubbed “Crooked Hillary,” released her 2015 tax returns already.

Trump is in the habit of casually making serious accusations. Whether it’s his remarks about Barrack Obama’s citizenship or his insinuation that Ted Cruz’s father was involved in the JFK assassination, he has never been one to shrink from a good jab.

I think it’s only reasonable to expect accountability from someone who is so unrelenting in his suspicion of others. As Mark Twain said, “Give someone a reputation for being an early riser and he can sleep ‘til noon.”

By calling Hillary Clinton “crooked,” the implication is that he is not. It’s time for him to back this up by doing what presidential candidates have been doing for decades.