ET special correspondent Diane Dimond, who has been covering Michael Jackson news since 1993, responds to the explosive new allegation that the King of Pop was gay.

In his new book, Ian Halperin, author of Unmasked: The Final Years of Michael Jackson, raises questions about Michael's sexuality. The author claims that whenever Michael would go out to meet one of his alleged gay lovers, he would wear an elaborate disguise.

"He was always dressed as a woman, and very convincingly, to the point no one else would recognize Michael," Halperin says in an interview with ET. "He was a master at costume -- at showbiz. He could've been a professional make-up artist he was that good."

Dimond says her findings do not jibe with those in Unmasked.

"Here's what I think," Diane says. "Over all the years that I have been looking into his life, I have found no evidence that Michael Jackson was gay. I have never spoken to any men who have claimed and proven they were Michael's lovers."

The question of Michael's sexuality was even something that his mother, Katherine Jackson, addressed. In 1993, she called those who said Michael was gay, "liars."

"Michael's appearance makes a lot of people think he's gay, but Michael is not gay," Katherine said. "He's not gay, I'm here to say, and this is what a lot of people think because of the way he looks. But you can tell when a person's gay, sometimes you look in his face and you say, 'Oh, my God, that guy is gay.' You can tell from their movement and all. Michael is not gay."

Keep checking back for the latest on the Michael Jackson investigation, and tune in to ET tonight for more of Ian Halperin's interview.