Bill Cosby, Cosby: His Life and Times (inset) Bill Cosby, Cosby: His Life and Times (inset)

Mark Whitaker, whose extensive biography on Bill Cosby was released earlier this year, has apologized for completely ignoring the numerous rape allegations against the comedian.

His admission came after The New York Times' David Carr owned up to being one of Cosby's "media enablers" and called out others whom he felt had done the same. This included writers for The New Yorker, The Atlantic and Whitaker, "who did not find room in his almost-500-page biography... to address the accusations that Mr. Cosby had assaulted numerous women, at least four of whom had spoken on the record and by name in the past about what they say Mr. Cosby did to them."

Bill Cosby rape allegations: Everything you need to know about the scandal

On Monday night, Whitaker tweeted Carr and admitted that the allegations against Cosby should have been included in Cosby: His Life and Times: "David you are right. I was wrong to not deal with the sexual assault charges against Cosby and pursue them more aggressively. I am following new developments and will address them at the appropriate time. If true the stories are shocking and horrible."

In an article published by The Daily Beast last week, Whitaker had attempted to defend his decision to leave out the allegations, saying he didn't want to inaccurately prejudice readers against Cosby with things he could not confirm.

"I wasn't going to reprint the allegations. I had a couple of reasons for that," Whitaker told The Daily Beast. "You can do that and say here's an allegation, and here's a denial, but given the nature of the allegations, the allegations would stick. As a biographer, you're really trying to say 'I'm painting a scene for you. Here you are in the room. This is what happened.' And if you do enough reporting, you can actually do that. And if you can't do that, you don't do that. When you're writing a book, you want to make sure it's really accurate, that you can stand behind it, because once it's out it's not like a piece in a newspaper or even a news magazine that you can correct quickly. That was just the standard I used."

However, Whitaker also acknowledged "the story has changed" and that he plans on addressing "that in future editions of the book, if not sooner." "If it happened, and it was a pattern, it's terrible and really creepy. ... I was just having a discussion with my son about this, and psychologically, if it happened... it's sort of compartmentalization," Whitaker said.

Nearly 20 women have come forward so far with stories of sexual assault dating back decades, but Whitaker said he believed Cosby has already "paid a big price" for the alleged assaults, which were first reported in 2005. "The show [a planned NBC sitcom] has been yanked. The reruns of The Cosby Show have been taken off the air. He's routinely called a rapist everywhere. That's a big price," Whitaker said, noting that he thinks Cosby's public image might still be saved.

"There might be an Oprah interview or something like that. There are things you can kind of imagine. ... Maybe he could suck it up and make amends by giving a whole bunch of money to anti-sexual abuse causes or something," Whitaker said. "He still has a fan base. I think people will still turn out for him. ... If he can't continue to perform, that will be the hardest thing for him. But if he can still go into arenas, and people will come and laugh at his stories, then he'll survive. That's what he's always cared about the most.

"I certainly would not have anticipated the degree to which this has become a huge issue again," Whitaker continued. "What you eventually learn about everything related to these allegations, and how you think that should figure in your ultimate judgment of Bill Cosby has to be weighed — and should be weighed — in the balance with a lot of the stuff I reported in the book more thoroughly than anybody else."

Meanwhile, the fallout continues for Cosby. The New York Post's Page Six reported Tuesday that in 1989, Cosby leaked his daughter Erinn's drug problem to The National Enquirer in exchange for the tabloid killing a planned story about him "swinging with Sammy Davis Jr. and some showgirls in Las Vegas." My editor told me that daddy Cosby was the source. He ratted out his flesh and blood," an Enquirer source told Page Six.