In a new ITV documentary airing tonight, Rogério Alves - family lawyer for Kate and Gerry McCann - says time is running out on the Madeleine McCann investigation.
In a clip from the upcoming programme, Madeleine McCann: The Hunt For The Prime Suspect, Rogério explains in Portugal, there is a "15 year barrier" to manslaughter, homicide and kidnapping and as we know, the investigation into the disappearance of Madeleine has now been ongoing for over 13 years.
"We have a 15 year time barrier to manslaughter, to homicide, also to a certain kind of sexual offences and even to the most serious kind of kidnapping. So we are still on time. But time's getting short now," he explained.
Earlier this year, convicted sex offender, Christian Brückner, was named as the prime suspect in the case and prosecutors have now issued appeals for more information.
The doc will shine a light on the mistakes that were made earlier on in the case, which could have stopped Brückner from being identified as a suspect.
The ITV documentary also hears from Brückner's lawyer, Friedrich Fülscher.
"At this time, we have advised the accused to remain silent. But that doesn't mean he has anything to hide," he says.
"Initially, making use of your right to remain silent is entirely normal in the context of defence."
The documentary will also delve into one piece of evidence that a phone allegedly belonging to Brückner was 'pinged' by a cell phone tower in Praia da Luz on the night Madeleine went missing.
In a second clip from the programme, public prosecutor Hans Christian Wolters explains: "We're now looking for the other person who was on the call. We want to know what they talked about.
"But we also want the other person to tell us who they were talking to. The data only shows that the phone was there, not who used it. That's why the other person on the call would be so important to us.
"They could tell us who they spoke to, possibly our suspect. In that regard, it could result in a conviction."
As criminal law specialist, Dr Alexander Stevens points out in the clip however, the biggest challenge for prosecutors when it comes to witnesses is that "any confidante would have to incriminate himself.
"Once you are involved in a murder crime they would have to at least be sentenced to 10 years in prison so the chances of getting someone to come forward are actually quite low."
The documentary will explore the mistakes made by police after Madeleine went missing, 13 years ago in Praia da Luz, Portugal.
Dr Graham Hill, a former detective for Surrey Police, who flew to Portugal in 2007 to help find the three-year-old, claims lessons from the case have still not been learned, 13 years on.
"What are we going to learn? How are we going to stop this happening again?" Asks Dr Hill. "If a child went missing on a beach in Europe, this summer in 2020, what would be done differently?
"You can abduct a child in one European country. And in 24 hours drive right across Europe. And I'm not so sure that much or anything different will be done because I'm not so sure we've learned the lessons."
This will be a gripping watch - be sure to catch it tonight on ITV at 9pm.
Featured Image Credit: PA