Kate McCann and her husband Gerry are suing Goncalo Amaral in a Lisbon court for the book in which he argues Madeleine was killed accidentally and implicates her parents in her alleged 2007 death.
The McCanns have strongly denied the accusations and say the former inspector's claims have hampered the search for their daughter and exacerbated the anguish suffered by her relatives.
The McCanns' spokesman Clarence Mitchell said, "Kate and Gerry McCann remain very confident that they will win the case.
Kate McCann could have been called as a witness but is not expected to give evidence.
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Instead, a number of relatives of the McCanns will appear in the witness box to give evidence about the "damage" caused by Amaral's book which, they also claim, poisoned public opinion in Portugal against the family.
The family are seeking the equivalent of USD 1.2 million euros, USD 1.6 million in damages.
The McCanns have unsuccessfully tried to ban the book. It was taken off sale but is now back on the shelves.
She was just a few days short of her fourth birthday.
Her parents believe she was kidnapped and is still alive.