Trump's record as one of the 'dumbest students' in college makes cheating story credible: Trump biographer
Donald Trump (Olivier Douliery:AFP)

On Tuesday, Trump biographer David Cay Johnston discussed the allegation from Mary Trump's book that the president paid for someone to take his SAT — an accusation he denies vehemently.

"He claims he was a top student, best of the best. What do you make of this, David?" asked host Erin Burnett.

"The story makes perfect sense," said Johnston. "First of all, back in the 1960s, it was easy to have someone go and take your test for you. There weren't IDs and the checks we have today because of the kind of cheating. The idea that a rich boy paid someone else to take the test, to people of my generation, is no surprise. Trump claims he was a great student, yet one of his former professor described him as the 'blank blank dumbest student he's ever had,' but thinks he knows everything. There were no honors for Trump at Fordham or Penn."

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