McCanns will use US evidence to challenge 'scent of death' claims

Kate and Gerry McCann will use a legal ruling in the US to counter the only evidence put to them during police questioning – the discovery of a scent of "death" by a sniffer dog in their apartment and hire car. A judge in Madison, Wisconsin, dismissed cadaver dog evidence last month in the high-profile case of Eugene Zapata – who is accused of murdering his estranged wife – because in his opinion it was no more reliable than "a flip of a coin".

The McCanns' legal team has consulted the lawyers in the US case and a source close to the family said yesterday that their lawyers are to take possession of the court papers shortly.

"It clearly could not be relied upon in that case and may well be equally as unreliable in Portugal," said the source. "There are wholly innocent reasons for everything that the police may have found which gives them cause for suspicion. Kate and Gerry have absolutely nothing to hide and are making sure they are well equipped to defend themselves."

The family source's revelation yesterday that the cadaver dog evidence is the only aspect of the case put to them during police questioning is astonishing. It calls into question precisely what evidence the police have against the couple and why, since they are officially arguidos (suspects), more wasn't put to them before they left Portugal. Instead, Portuguese police have submitted 40 questions to the couple, via the European law enforcement agency Europol, and will ask Leicestershire Police to put these to the McCanns.

A British springer spaniel picked up a "scent of death" on everything from Mrs McCann's clothes to Madeleine's favourite soft toy Cuddle Cat, according to some reports in Portugal. The daily newspaper journalist Nuna Miguel Marrier, with whom the police have regularly discussed the case, has told The Independent that it is the combination of cadaver dogs and DNA traces that has made the McCanns' apartment and car such a focus of inquiry.

But experienced British murder squad officers have said all along that sniffer dogs cannot replace detective work in this case. Dane County Judge Patrick Fiedler ruled in the Zapata case that the evidence that led to the charge could not be put before the jury. The judge agreed with an analysis of the three dogs' track record by Zapata's defence team that found they were incorrect 78 per cent, 71 per cent and 62 per cent of the time.

After a desperate first week back in Rothley, Leicestershire, the McCanns – who attended a service in the village church yesterday morning, learned that the Archbishop of York Dr John Sentamu had come to their defence. "Kate and Gerry have been treated unjustly and inhumanely, because the evidence does not stack up at all," Dr Sentamu told the BBC. "There is this great injustice which they feel is piled upon them." Dr Sentamu added that the police focus should be on finding Madeleine.

Sir Richard Branson has also announced a donation of £100,000 to ensure the couple get "a fair hearing". The McCanns have just unveiled an £80,000 advertising campaign to publicise Madeleine's disappearance.

The judge who is considering the prosecution case, Pedro Frias, has asked Portugal's magistrates council for permission to speak freely about the case in an attempt to settle some of the chaos being caused by random police briefings to the Portuguese press, which seem to have contributed to the decision of Chief Inspector Olegario Sousa – spokesman for the inquiry – to stand down at the weekend.

There were suggestions for a second successive day in the Portuguese press that a reconstruction of Madeleine's movements on the night of 3 May may be undertaken, with the police keen to involve the McCanns and the friends who were with them.

But with nothing else to report on, the Correio da Manha newspaper resorted to a new, veiled attack on Mrs McCann, based on the shops she visits in Leicester and the hairdresser she uses.