In his books, conservative author Bernard Goldberg rails against left-wing bias in U.S. media. But, as evidenced by a recent appearance on Fox News, he's still got an eye for overt right-wing slant.

Speaking to Fox editorialist Bill O'Reilly on Tuesday night, Goldberg slammed the network's "cheerleading" of tea party protests and expressed opposition to those who pretend to be journalists while twisting facts to promote their opinions.

"There are some programs on Fox that are not only not 'Fair and Balanced' -- they're commentary shows, they don't have to be -- but they brag about how 'Fair and Balanced' they are," Goldberg said. "They don't cover rallies and tea parties, they cheerlead for rallies and tea parties. And as a journalist, I am totally against that."

O'Reilly responded by equating pervasive Fox News bias with newspapers' editorial pages, usually a properly labeled, set-aside portion of the paper devoted exclusively to opinion.

"What's the difference?" he demanded of his guest. "Come on, it's a big question, Bernie! What's the difference?"

"Don't pretend that you're objective -- and I don't mean you, I mean others on this network," Goldberg replied. "Don't go on the air and say these tea parties are a cross section of America. They are not a cross section ... Don't pretend to be a journalist if you're not a journalist."

While O'Reilly seemed indignant at Goldberg's criticism of his host network's practices, he concluded at the end of the segment, "That's legitimate and should be criticized."

This video is from Fox News' O'Reilly Factor, broadcast Sept. 29, 2009.