I voted yes, that JA has more of a right to write the book.
If we are talking about constitutional rights, everyone has the same right to write a book. The reason I voted for JA having more rights is that I believe his book will be non-fiction, and non-fiction is what this story requires.
The As or A-supporters will write from their viewpoint, or will write what they want people to hear whether it is factual or not, IMO. They will embellish and they will continue to excuse KC's behaviors as well as the behaviors of all the Anthonys and the defense. It would, IMO, be a work of fiction pretending to be non-fiction. And that is inappropriate in more ways than I can say.
Anyone who wants to publish the truth has not only the right but the responsibility to do so, IMO. Anyone who wants to publish lies also has the right--but it would be very irresponsible, IMO.