Time is running out for Portugal police to convict someone for the disappearance of Madeleine McCann.
Portugal law prevents prosecutions after 15-years and legal experts say the time limit means putting anyone behind bars would be "greatly reduced".
Police would have to convict a suspect by May 3 - the 15th anniversary of when McCann disappeared from the Portugal seaside town of Praia da Luz.
The current suspect is German national Christian Brueckner - who lived near the resort where McCann went missing. He's currently in jail as a convicted paedophile.
Police would need to declare Brueckner as an "official suspect" by May 3 this year to keep the case alive.
Spencer Dohner, of MDM Legal in Faro, said Portugal's statute of limitations states anyone behind a crime punishable by 10 or more years' jail "cannot generally be prosecuted once 15 years have passed", UK tabloid The Sun reported.
"If Madeleine is dead and was murdered the cut-off point for prosecution would be the 15th anniversary of her disappearance," Dohner said. "If she were found alive and had been the victim of sex crimes as a minor, legal proceeding could take place until she was 23. She is now 18," he told The Sun.
The new time frame revelations come after Brueckner "repeatedly" worked at the Portuguese resort where McCann vanished from in 2007, a new documentary claims.
In the documentary, New Leads in the Maddie Case, an anonymous witness claims convicted rapist Brueckner "regularly carried out repair work" as a maintenance man at Ocean Club in Praia da Luz, where the three-year-old disappeared almost 15 years ago. He was reported to be "very familiar" with the resort and the surrounding area.
There are also reports of the London Metropolitan Police's long-running, multi-million-dollar operation into the disappearance of McCann set to end due to a lack of leads - but the daughters' parents are believed to have private funding to continue the search.
