Prominent African-American academic Michael Eric Dyson on Sunday accused Donald Trump of propagating "racism by inference," and said his recent questioning of President Obama's background was "shameful" and "sad."
Trump has in recent months earned both attention and criticism forthat the president may not have been born in the United States.
Now, even after Mr. Obama released his long-form birth-certificate, Trump has continued to question the president's background - namely attempting to.
"The word is [the president] wasn't a good student and he ended up getting into Columbia and Harvard,", vaguely citing things he had read in the media when asked about his source on Mr. Obama's academic performance: "I'd like to know, how does he get into Harvard? How does he get into Columbia if he isn't a good student?"
Mr. Obama received an undergraduate degree from Columbia University in 1983, and then went on to Harvard Law School, where he graduated magna cum laude. He was also president of the Harvard Law Review, the first African American in that position.
Dyson, in an appearance on CBS' "Face the Nation," said Trump's accusations about Mr. Obama's history were meant to imply that "Obama is not up to snuff.
"This is racism by inference," he told CBS' Bob Schieffer. "Skepticism about black intelligence and suspicion about black humanity have gone hand in hand throughout the history of this country in feeding the perception that black people don't quite measure up."
"The reality is that Barack Obama has been called to account by a man who has nothing near the intellectual credibility or the social standing that the president has," he added.
Condemning Trump's efforts promote what he described as "conspiracy theories, half-hearted truths [and] factual errors," Dyson argued that attacking the president's academic history was "retroactive bigotry" - and that Republicans should clarify their positions on Trump's claims.
"Unfortunately, Donald Trump has commandeered the bully pulpit," Dyson said. "If he is indeed the voice of Republicans, they ought to say so. But if not, they ought to distance themselves from him and suggest that this obsession with the birth of Barack Obama has to be put aside to deal with more serious and sustained issues.
"Make no mistake: This is part of a racist trajectory," he added.
Dyson defended the White House's recent decision to release Mr. Obama's long-form birth certificate, arguing that although the "birther" issue "was ended among reasonable people a long time ago," the president effectively had no alternative.
"He had no choice," Dyson told Schieffer. "He used it to his strategic advantage, but he had no choice but to give in to the vicious bigotry out there [and] say, 'Let's put an end to this.'
"He is standing in for the rest of us as African-Americans," Dyson continued. "We are constantly questioned as to our legitimacy - whether we belong or not - and Barack Obama is our big brother in that case. ... An assault on him is an assault on everybody."