LISBON, Portugal — An appeals court in Portugal has overturned the libel conviction of a former Portuguese detective who published a book alleging the parents of missing British girl Madeleine McCann were involved in their daughter's disappearance, the parents' lawyer said Tuesday.

Lisbon lawyer Isabel Duarte told The Associated Press she was notified of the court's decision to uphold Goncalo Amaral's appeal against the order to pay Kate and Gerry McCann 500,000 euros ($568,000) in compensation. That ruling was handed down by a lower court in Lisbon a year ago, prompting Amaral to appeal.

Duarte said she intended to fight the decision at the Supreme Court, though she hadn't yet assembled her legal arguments.

Amaral was part of the police investigation into Madeleine's disappearance from a vacation home in Portugal's Algarve region in May 2007, days before her 4th birthday. In 2008 he published his book about the case called "The Truth of the Lie."

The McCanns sought 1.2 million euros in damages from Amaral, saying they were "totally destroyed" and "depressed" by Amaral's allegations and felt "ashamed" that they might appear to have been to blame for their daughter's disappearance. Amaral had argued in his defense that his claims stemmed from the police investigation and that Portuguese media had already reported the possibility that the parents might have played a role in Madeleine's disappearance.

The appeals court "decided that (Amaral) had the right to do what he did. It said he can write what he wants," Duarte, the lawyer, told the AP by telephone. "It absolved him, said he didn't have to pay anything."

She said the McCanns took the reversal in their stride after a long time battling in Portuguese courts.

"They're used to it," Duarte said.

Portuguese police closed the case in 2008 because authorities had detected no crime, but British police are still looking into it. Madeleine would turn 13 next month.