Kentucky Sen. Rand Paul’s interview on Boston’s NPR station WBUR Tuesday turned testy after host John Harwood asked him about former adviser Jack Hunter.

Harwood, the chief Washington correspondent for CNBC, author of The New York Times’ weekly column The Caucus, and Tuesday’s guest host on the program “On Point,” dug into the controversy over Hunter, a former Paul aide better known by his radio moniker, the “Southern Avenger.”

“What conclusion should people draw from the presence of that former shock-jock Jack Hunter, on your staff who co-authored a book with you, who was identified as the ‘Southern Avenger’?”

Though Paul insisted that Hunter is no longer a part of his staff, Harwood reiterated the possible presidential candidate’s close associations with Hunter, who even co-authored his book.

Paul responded by emphatically separating himself from his former aide and defending his own credentials, saying that he was not aware of the controversial writings.

“I think some of the things he wrote or many of the things he wrote were stupid and I don’t agree with. They weren’t things I was aware of, or reasons why I hired him,” he told Harwood. “I do think though that he was unfairly treated by the media and he was put up as a target practice for people to say he was a racist, and none of that’s true.”

“He got along fine with everybody in the office, treated everyone fairly, regardless of race or religion, and we have a very varied office staff and backgrounds, so I think that it was just unfair,” Paul said. “But it’s also unfair to paint a broad brush and say that’s who I am, when I should be judged by the things that I’m doing.”

“And I think there is no greater defender, truly, of minority rights, if you include minorities to be color of your skin, or the color of your ideology than myself,” he continued, “because I will stand up there with the most progressive members of the caucus in the Senate and say, ‘You know what, civil liberties are important. They’re important particularly because of some the egregious things that happened in America’s history.'”

Harwood then asked for comment on an excerpt from an article in The Economist that read, “The only notable libertarian-leaning politicians to generate real excitement among conservative voters have risen to prominence through alliances with racist and nativist movements.”

“Don’t you have something better to read than a bunch of crap from people who don’t like me?” an irritated Paul asked. “I mean, that won’t make for much of an interview if I have to sit through, you know, reading after recitation of people calling me a racist.”

“I don’t accept all of that, and I don’t really need to, or spend the time going and talking about that,” Paul added. “If you want to talk about issues and what I stand for, I’m happy to. But I’m not going to really go through an interview reciting and responding to every yayhoo in the world who wants to throw up a canard.”

Harwood again brought about Jack Hunter, and the senator responded, “Well, why don’t we talk about Rand Paul? I’m the one doing the interview and you can go ahead and beat up on an ex-employee of mine, but why don’t we talk about Rand Paul and what I’m trying to do to grow the party, and then we might have an intelligent discussion.”

After Harwood insisted that he was indeed trying to have an intelligent discussion, Paul responded, “Well, you’re not.”

“You think you want to dwell on something, that you want to bring up critical articles from people who don’t like me and don’t support any libertarian ideals,” he continued. “Why don’t we talk about what libertarian Republicanism means and what it would do for the party? Let’s talk about some issues, let’s talk about indefinite detention, let’s talk about aid to Egypt, let’s talk about repatriation of foreign capital so we could redouble our infrastructure which the president asked for last week. Those might be some pertinent topics other than doing ad hominem on me.”

Harwood responded, “Let’s talk about transportation.”

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