DOZENS of men accused of downloading child pornography from the internet may have been wrongly prosecuted, according to expert prosecution and defence witnesses.

New evidence suggests that Operation Ore, Britain’s biggest child pornography investigation, may have prosecuted innocent men on the basis of discredited American police testimony and questionable forensic methods.

Jim Bates, a computer expert who has served as a witness for the prosecution or the defence in more than 100 child porn cases, says many Ore cases are now likely to collapse or be overturned in the Court of Appeal. “It has been a shambles from the word go,” he said.

The nationwide police investigation was launched three years ago after a list of 7,200 British suspects was supplied to British police by American authorities.

The men on the list stand accused of having used their credit cards to pay for child porn through Landslide, a sex website that operated in Texas from 1996-9.

The accusations have led to 33 suicides, most recently that of Commodore David White, the commander of British forces in Gibraltar. He was found dead in his swimming pool on January 8.

Bates believes records of credit card transactions on the site are unreliable and therefore the names of alleged subscribers cannot be used as evidence.

Thomas Reedy, the man who set up the website, was investigated by the FBI in the 1990s for credit card fraud. “I am convinced that a massive fraud has been perpetrated at Landslide and an unknown number of subscriptions are fake,” said Bates.

He cites the case of Dr Paul Grout, a senior accident specialist at Hull Royal Infirmary, who was falsely accused of accessing child porn. Grout, who was praised for his help at the 2001 Selby rail crash, lost his £70,000-a-year job because of the allegations. Many of his friends “drifted off” and he and his wife Susie endured huge strains on their marriage.

It was not until his case came to Hull crown court in April last year that the Yorkshire doctor was able to prove his innocence. His lawyers showed that, while Grout had used his credit card to pay for a meal in a restaurant in Yorkshire, someone else had been using it 5,000 miles away in Lake Tahoe, America.

In a case that legal experts believe may prove a landmark judgment, Judge David Bentley threw out the prosecution argument. In his judgment, Bentley dismissed some police evidence as “utter nonsense”. He said the way the Crown Prosecution Service (CPS) had held back some information vital to Grout’s defence had “stunk of unfairness”.

Another computer user wrongly accused of downloading child pornography was Robert Del Naja, frontman of the group Massive Attack. His arrest in February 2003 was leaked to the media but the case against him was dropped less than a month later.

One police officer, Peter Johnston, became so disillusioned at what he described as the Ore “witch-hunt” that he resigned from his job with Merseyside police.

In a letter to The Sunday Times, Johnston said: “I began to doubt the validity of the evidence surrounding the circumstances of the initial investigation in America . . . I found it difficult to rationalise how offenders had been identified solely on a credit card number.”

Bates believes that evidence, highlighted by Duncan Campbell, an investigative journalist and an expert witness in some Ore cases, could lead to many cases being dropped.

In an article in last week’s Sunday Times, Campbell revealed that sworn statements provided in British courts by two American detectives who initiated Operation Ore could no longer be relied upon.

The two, Dallas detective Steve Nelson and US postal inspector Michael Mead, had claimed that everyone who went to Landslide always did so through a front-page screen button saying “Click Here (for) Child Porn”.

But Campbell has established that the button was never on the website’s front page. Instead it was on an advertisement for another website buried deep in the Landslide website.

That discovery has effectively removed a key plank of many of the Ore prosecutions where no actual child porn was found.

Those prosecutions were based on the assertion that evidence that someone had paid to access Landslide automatically meant that they had paid to access child porn.

Steve Barker, a solicitor who acts for one Operation Ore suspect in a High Court appeal, said that in many prosecutions police were unable to disprove defendants had simply accessed legal adult porn rather than paedophile material. In other cases, child porn might have been accessed accidentally by those looking for adult porn.

The CPS has also disclosed that an internal inquiry has raised serious questions over the evidence provided by Brian Underhill, a key police witness in some 600 Ore cases. The CPS said it would now disclose the doubts raised by its inquiry to defence solicitors before future trials began.

The CPS last week defended its role in the hundreds of successful cases in which defendants had pleaded guilty. A spokeswoman said: “Each case was considered on its own merits and the evidence provided by police has been subject to thorough scrutiny.”