According to the News, Baker is circulating a book proposal to publishers in which she writes that she was present when her uncle "invented his alibi and rehearsed it with" house guest Kato Kaelin.
Baker also is said to claim that many family members share her doubts about Simpson's story. "In an unguarded moment soon after the murder of Nicole, my grandmother, Eunice Simpson, exclaimed in my presence, 'He did it!'"
The paper also quotes the book proposal as saying that Simpson resented his family and "pushed us into the remote corners of his life...We were too black, too ordinary for him."
The book, titled I'm Not Dancing Anymore, is represented by the Renaissance literary agency in the Los Angeles area, according to the News. The agency wouldn't comment on the story today.
Baker would be the first family member to break with Simpson publicly. His close friend and attorney, Robert Kardashian, has also gone public with his doubts--he's the one who revealed that Simpson flunked a lie-detector test.