Dr. Phil, David Letterman Dr. Phil, David Letterman

David Letterman says Donald Trump is a racist for suggesting that President Barack Obama was unfairly accepted into Ivy League schools.

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Dr. Phil — who's friends with the Celebrity Apprentice host — and was visibly annoyed at Trump's questioning of Obama's transfer into Columbia University and acceptance into Harvard Law School."It's all fun, it's all a circus, it's all a rodeo, until it starts to smack of racism. And then it's no longer fun," Letterman said. "Do you consider him to be a racist?""I do not," Dr. Phil replied."How can you say things like that if you're not a racist?" Letterman asked.

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"I don't think he always thinks everything through," Dr. Phil said. "I think sometimes he's a little from the hip, and I don't think he has a racist bone in this body."But Letterman's not buying the doc's defense yet. "If he comes back on this show, and I'm not sure we want him back under those circumstances, but he ought to be prepared to apologize just for that kind of behavior."Watch the exchange below. Do you agree with Letterman?