Editor’s Note: Errol Louis is the host of “Inside City Hall,” a nightly political show on NY1, a New York all-news channel. The opinions expressed in this commentary are solely those of the author.

Story highlights

Errol Louis: Donald Trump's press conference turned into a tantrum over questioning by the media

He says Trump has a record of lying and the media need to double-check facts of what he says

CNN  — 

Donald Trump’s press conference tantrum Tuesday – during which he called one reporter “a sleaze” and lashed out at others for seeking verification of a $1 million charitable gift he claimed to have made to veterans organizations – is the inevitable result of months of fact-twisting, distortions and outright falsehoods uttered by the candidate on a daily basis.

The truth of the matter is that reporters have very good reasons to take Trump’s claims with a grain of salt – and to ignore the name-calling, mockery and insults he uses to try and distract journalists from double-checking nearly everything he says.

Trump routinely and repeatedly says many, many things that are simply untrue. Not only were members of the press justified in skeptically asking Trump to prove he made the donations he’d boasted about, they – we – are especially required to verify any of the candidate’s assertions, because they so often turn out to be at odds with the facts.

In the case at hand, Trump made a big deal of his claims – announced on national television in January – that he had raised $6 million to donate to veterans organizations, including $1 million of his own money. That turned out to be not quite true: Trump only coughed up the million on May 24 – months after his promise – on the same day that sharp-eyed Washington Post reporters called to find out if and when the donation had occurred.

“The press should be ashamed of itself,” Trump said at his press conference. “You make me look bad.”

Quite the contrary: The press should be proud of the work it did.

More than a dozen of the veterans organizations funded by Trump told The Washington Post they only got their money last week, several in the form of checks via overnight mail on the day the Post pressed Trump to explain where the long-delayed donations were. If reporters hadn’t asked, it’s unclear when or whether the groups would have seen any of the money Trump promised.

Cynics might say that Trump’s no different from other candidates, and that all politicians tell lies. That may be. But the size, frequency and brazenness of Trump’s are so off the charts that they have drawn considerable commentary.

“The thing about Trump is that he’s so blasé about lying, and does it so frequently, that people tend to forget how many made-up facts they’ve heard from him,” wrote Rob Garver, a longtime Washington-based reporter, in The Fiscal Times.

Remember that this is the candidate who peddled – and to this day has not renounced – garbage claims that President Barack Obama was not born in the United States and then never produced any evidence.

Trump is also the candidate who falsely said: “I watched when the World Trade Center came tumbling down. And I watched in Jersey City, New Jersey, where thousands and thousands of people were cheering as that building was coming down. Thousands of people were cheering.”

Not true. No news organization or elected official ever confirmed Trump’s account, which he has never renounced. This is the same candidate who mocked a disabled reporter, Serge Kovaleski, on the campaign trail, then denied the childish antics the whole world had just seen.

When The Huffington Post assigned five reporters to scour the record of one of Trump’s presidential debate performances, the team concluded: “It took us hours, but in all, we found 71 separate instances in which Trump made a claim that was inaccurate, misleading or deeply questionable. That’s basically one falsehood every 169 words, or 1.16 falsehoods every minute.”

It doesn’t stop there.

In two different books, Trump said he staged a comeback after being $9 billion in debt – but when asked about the claim under oath, he acknowledged the figure was completely wrong, adding, “Frankly, whether it’s $9 billion or $3.6 billion, I don’t think makes any difference to anybody if they hear the story.”

And Trump is being sued by New York State Attorney General Eric Schneiderman for allegedly defrauding thousands of customers of Trump University – which was, of course, not incorporated or licensed as a university at all, and initially ignored government warnings not to call itself one.

According to Schneiderman, people were charged thousands of dollars for courses on real estate that never began to live up to Trump’s promises.

“If you look at the facts of this case, this shows someone who was absolutely shameless in his willingness to lie to people, to say whatever it took to induce them into his phony seminars,” Schneiderman says. “It was shameless. It was heartless.”

Trump may not enjoy the media scrutiny that comes with being a candidate for president, but it is the job of a free press to bring truth to light. One school of thought holds that Trump will win politically by attacking the press. That assumes that the public has no concern about learning when a candidate is exaggerating, distorting or fabricating information.

I prefer to think that voters are still in the information-gathering stage and will make a decision sometime between now and November 8 about how much any given fact matters.

That makes it the job of the press to do exactly what happened in this case: check and double-check everything the candidate says, whether he likes it or not.

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Errol Louis is the host of “Inside City Hall,” a nightly political show on NY1, a New York all-news channel. The opinions expressed in this commentary are solely those of the author.