The parents of Madeleine McCann hope they have at last turned the corner in the propaganda war with the Portuguese police after more than a month in which their reputation has taken a public battering.

Despite the strict secrecy laws surrounding Portuguese criminal investigations, senior officers began briefing newspapers in the middle of August that Kate and Gerry McCann were suspected of killing their daughter and hiding her body. The McCanns were in a weak position, having prevaricated about appointing a lawyer. They had hired an expert in campaigning, Justine McGuinness, rather than someone to defend their reputations.

On September 7 Mrs McCann was taken into the headquarters of the PolÍcia Judiciária in Portimão to a chorus of boos from among the hundreds of people waiting outside. During a break in her first grilling, Mrs McCann telephoned her husband to say that detectives had advised her to confess to killing Madeleine in exchange for a lenient sentence.

Soon afterwards a relative back in Britain appeared on television talking about the development. “The cops went mad and were swearing at the screen and they turned aggressive towards Kate,” said a source.

Two days later as the couple flew home to Leicestershire the newspapers were full of details about the cast-iron evidence that made senior detectives convinced that the couple were guilty. But the following Friday the tide begun to turn with the Portuguese media for the first time questioning the strength of the evidence against the McCanns.

The McCanns knew that even if the Portuguese authorities did not have enough evidence to charge them, their reputation had been left in tatters.

On Monday last week the former BBC reporter Clarence Mitchell returned to support the McCanns as part of a formidable team that includes leading British solicitors Michael Caplan, QC, and Angus McBride, and two of Portugal’s most prominent lawyers, Carlos Pinto de Abreu and Rogerio Alves.

The McCanns have gone on the offensive. They tore into the “evidence” from a sniffer dog which it is claimed smelt traces of a corpse in the McCanns’ apartment and hire car and explained how apparently damning DNA evidence might have an innocent explanation. Friends publicly spoke about the couple’s devotion to their children while other sources revealed details of the events leading up to Madeleine’s disappearance.

A family source said: “We are getting the message across that Kate and Gerry have nothing to hide. It is for the police to prove they are guilty. Some people will say there is no smoke without fire, but we want them to know there is no basis for these claims.”

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