Police, prosecutors and leading psychologists have raised fears that the internet is “normalising” abusive sexual behaviour towards children.

As he jailed James Rennie and Neil Strachan for life yesterday, Lord Bannatyne underlined the mounting concerns as he singled out Rennie as the prime mover in a conspiracy to abuse babies and young boys, likening him to a spider in an electronic web “bringing to fruition this appalling crime”.

Rennie’s kplover99 e-mail account had links to paedophiles in Europe and North America, including the notorious Matthew Grasso — who was arrested for holding a collection of 150,000 abusive images at his home in Salem, Massachusetts. Lord Bannatyne said that any such activity helped to maintain the market in abusive images.

“If there were fewer people willing to download such material, either for their own use or with the intention of distributing, the encouragement for those who manufacture these photographs, with all the clearly serious effects such manufacture must have on children, would be lessened,” he said.

Ethel Quayle, a lecturer in clinical and social psychology at Edinburgh University, said that it was impossible to share material on such a scale before the advent of the internet. Operation Algebra, which had led to the jailing of Rennie, Strachan and six other members of their gang, had been an outstanding police investigation but raised “very disturbing concerns” about the increased propensity of some men to offend.

“Twenty years ago you couldn’t have walked into a sex shop and said, ‘I’m really interested in kids — can you point me in the right direction?’. The internet makes that possible,” said Dr Quayle, who helped to develop the Copine scale, a system which is used to assess the scale of abuse shown in images.

Worryingly, said Dr Quayle, studies on intimate sexual offending had focused primarily on either the psychology of the individual offenders or raised questions about whether online offences, such as collections of photographs and videos of abuse, were comparable with real-life attacks on children. These approaches, though valuable, neglected to address the dynamics between offenders who met online and then acted together to abuse children, she said.

“If you think about risk and recidivism, ‘hanging around with the wrong sort of people’ is something one would discourage — yet that’s what the internet promotes, both on line and moving off-line.

“Operation Algebra raises profoundly difficult questions about conspiracy in online relationships and this movement into offline activity and the singular role of fantasy.

“We can’t police fantasy, but how do we differentiate between fantasy which is just that and the movement from fantasy to actual behaviour?”

Immediately after sentencing, the Scottish police service announced a new initiative, Operation Alba, which officers believe will play a role in monitoring online traffic between offenders. It will use new techniques to monitor the distribution of abusive images on the web. A key component of the system enables detectives to monitor the transfer of some abusive photography on a “peer-to-peer” basis, or between users.

Assistant Chief Constable Iain Livingstone said that offenders could expect to be tracked down and face similar prison sentences to those handed down to Rennie and Strachan.

“We are utilising the most up-to-date technology to identify and arrest individuals who attack and abuse vulnerable children. We are making clear through Operation Alba that there is no hiding place, every contact via the internet leaves a trail that we will follow,” said Mr Livingstone, who holds the child protection portfolio for the Association of Chief Police Officers in Scotland.

Not all the data on sexual offences is bleak. The most recent statistics from the United States suggest that the level of attacks on children has fallen by a third in the ten years from 1990 to 2000, Dr Quayle said. However, she warned that evidence gathered by the Internet Watch Foundation and through child protection hotlines suggested “something disturbing which is embedded in everyday existence”. She noted that seven of the eight men jailed at the High Court had no previous convictions, a sign of a wider, frightening malaise.

“If you look at the volume of material online, and the level of trading, the reality seems to be that the people who are caught are only the tip of the iceberg.

“Do people choose to be sexually attracted to children? I have no idea. They do choose whether or not to act upon it. I have a theory that there are lots of people sexually interested in children, that it is maybe not be as unusual as we would like to think it is. It’s a question of how do we act responsibly?

“There may be some aspects to the internet that erode some of things that might otherwise have acted as protective factors.”

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