“I was looking at everything that would include them,” he said.
“If I found any evidence against Kate and Gerry I would have given it to the police immediately. Kate and Gerry would expect no less. But I found no shred of evidence.
“We obviously look at all factors – motive, preparation, opportunity – and there was absolutely nothing.”
Based on the evidence, Mr Edgar believes the kidnapping of Madeleine McCann was a planned operation.
“There was a very narrow window of opportunity for them to get away with Madeleine. So it does point to it being planned and some level of surveillance, perhaps of the apartment.”
He added: “If the motive was gang-related child prostitution, there might have been more than one involved.”
He believes that the breakthrough in the case will come from the people who the kidnappers have confided in.
“They can’t keep it to themselves and research has shown they always confide in someone else.
“I think that someone else apart from the perpetrator knows and that is one of the best hopes of getting to the truth, that someone comes forward and says what they know.”
This article originally appeared on Who.