Karam says the book is intended to put to rest the "so-called controversy" of whether David or his father, Robin, was responsible for the killings.
In effect, it lays out a prosecution case against Robin.
David Bain, with Karam's assistance, has lodged an official claim for compensation for 13 years in prison from his 1995 conviction until the Privy Council ordered a retrial in 2007.
Karam, who is also suing supporters of Robin Bain for defamation over comments they made on their website and on Facebook, indicates there is plenty more dust still to settle.
He refers to the actions of Constable Terry Van Turnhout, who admitted at the second trial that he had made an error of judgment by handling a key piece of evidence at the homicide scene - the broken glasses allegedly worn by Bain.
"Who knows, in another 15 years one of the detectives might come forward with some more evidence a la Van Turnhout's belated confession," Karam writes.
Bain now lives and works in West Auckland. Next month, he and Karam are to give a joint address to an international justice conference in Perth.
Karam says Bain's retrial and acquittal has failed to quell speculation.
"A whole lot of myths developed as a result of the manner in which the trial was covered," he said this week. "It was shallow and sensational coverage.
"In cases like this, people develop a belief and it's very hard to shake. My main wish in that regard is not to change people's minds, but at least open their eyes to the facts. I think those facts have never been espoused."
The books says the case against David Bain was "arguably predicated upon concealment rather than disclosure, arguments unsupported by the evidence, incomplete and defective scientific analysis, and in some instances, totally bankrupt knowledge."
In November, then Justice Minister Simon Power announced the appointment of retired Canadian Supreme Court Judge Ian Binnie to assess Bain's claim for compensation for wrongful conviction and imprisonment.
