'They lie so frequently': Trump biographer unloads on ex-president's family

Under oath, Trump and his kids can't hide their serial lying.

That's according to Trump biographer Tim O'Brien who branded the former president and his three adult charges as being unable to find the truth in their web of lies during an appearance on MSNBC's "The Last Word With Lawrence O'Donnell."

"You discover when you just put documents in front of the Trumps: tax returns, banking records, other parties' assessments of their wealth that they tie themselves in knots because they lie so frequently and so fluidly about everything, and they can't even be consistent about their lying," he said.

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The author of the 2005 book The Art of Being the Donald, said he had even conversed with a longtime adviser to Donald Trump who corrected him that the former president doesn't just lie, but that he's poor at keeping the lie straight.

O'Brien said the Trump advisor informed him, "You, know the problem with Donald isn't just that he lies, it's that he can't lie consistently."

He pointed out how when it comes to Trump's net worth, the 45th president is either unwilling or unable to even stick to a figure — shifting around from being worth as much as $6 billion down to $2 billion and free falling to $1 billion.

The advisor told O'Brien, "I want to tell him just say six, but he won't even stick with that story."

O'Brien believes that the Trump Organization embraced fibbing culture.

"The reality is, lying and dissembling is not a bug in the Trump organization," he said. "It's a feature. And today Donald Trump Jr. was exhibit A in how they roll around that."

The author harped on the fact that Don Jr. during his Wednesday testimony claimed to be oblivious to the so-called generally accepted accounting principle or GAAP that are the standard tenets that must be followed by corporate accountants.

When pressed to explain his experience Don Jr. claimed he did a little of everything save for the accounting and said, "that's what CPAs are for."

He went on to say that he and other executives paid such financial experts so that they would handle such things.

This showed ignorance on display for O'Brien.

"Don Trump Jr., not knowing anything about GAAP, allows [the Trump Organization] to make up the numbers," he said.

Trump's son was essentially passing the buck to the number crunchers.

"And he tried to pawn it off on his accountants," O'Brien said. "And I can tell you because I've see these documents, it wasn't pawned off on the accountants, because the accountants wouldn't sign off on the document."

He also blames Don Jr., Eric, and Ivanka for their complicity and for being "as ignorant as their father."

"They are comically ill-informed about everything under the sun, and that is another reason why they dissemble."

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