The Council of Better Business Bureaus is calling out Donald Trump for what appears to have been a brazen effort to mislead the Fox News hosts who moderated last week’s Republican presidential debate, as well as the millions of Americans who tuned in to watch last Thursday night.

During the debate, the moderators and Trump’s opponent, Florida Sen. Marco Rubio, brought up the subject of Trump University, a now-defunct business that Trump established to sell supposedly educational courses and seminars on entrepreneurship. Trump University is currently being sued for fraud by numerous former students, who said that they were pressured to take on debt to pay for tens of thousands of dollars in fees and that the company did not deliver the type of educational experience it promised.

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On stage last week, Trump angrily challenged criticism of Trump University, insisting that the organization had a “98 percent” approval rating among its students.

But it was when Rubio brought up the company’s D- grade from the Better Business Bureau that Trump really started to get creative.

He conceded that at one point the company did have a D- rating from the Better Business Bureau, but he said the rating was poor only because Trump University hadn’t bothered to submit data to the BBB. He insisted that the grade was subsequently “elevated to an A” once the data was supplied.

“The only reason that is was a D was because we didn't care -- we didn't give them the information...” Trump said. “When they got the information it became an A.”

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During a commercial break, Trump was given a fax from his staff, which he handed to Fox moderator Bret Baier. He later posted the document on Facebook. It appeared to be a BBB Business Review giving Trump University (actually, Trump Entrepreneur Initiative, after a 2011 name change) an A grade.

At least one news organization reported, at the time, that the document appeared to have been faxed to the Fox News set by the BBB itself.

On Tuesday, the Council of Better Business Bureaus issued a detailed statement setting the record straight.

“BBB did not send a document of any kind to the Republican debate site last Thursday evening,” it read. “The document presented to debate moderators did not come from BBB that night.”

It continued, “Trump University does not currently have an A rating with BBB. The BBB Business Review for this company has continually been “No Rating” since September 2015. Prior to that, it fluctuated between D- and A+. The document posted on social media on Thursday night was not a current BBB Business Review of Trump University. It appeared to be part of a Business Review from 2014.”

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More damning, though, was the BBB’s account of how Trump University’s rating went from a D- to an A. The BBB said that, despite Trump’s claims to the contrary, the rating was never increased as a result of new information received from the company.

What happened is that as Trump University failed as a business, it stopped attracting new students, and with no new students, there were no more complaints filed to the BBB.

“During the period when Trump University appeared to be active in the marketplace, BBB received multiple customer complaints about this business,” the statement said. “These complaints affected the Trump University BBB rating, which was as low as D- in 2010. As the company appeared to be winding down, after 2013, no new complaints were reported.

“Complaints over three years old automatically rolled off of the Business Review, according to BBB policy. As a result, over time, Trump University’s BBB rating went to an A in July 2014 and then to an A+ in January 2015.”

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In other words, Trump was lying about Trump University’s rating on national television, and even provided misleading documentary evidence in real time to help him make his case.

In a sane campaign season, this sort of thing would be utterly disqualifying, but whether it will have much effect on Trump’s core support is doubtful. The billionaire’s supporters have proven remarkably immune to factual arguments about Trump’s obvious deficiencies as a candidate, and uninterested in proof that he frequently lies to them.