The mother of a six-year-old boy who was subjected to what a judge described as “truly appalling” abuse from a man she had regarded as a close friend said yesterday that her child had been “shaped and moulded” for life by the experience.

Welcoming the life sentences passed on James Rennie and Neil Strachan, the woman said that she had moved on from feelings of anger. “My focus is about my son, about how to support him and loving him for who he is. And who he is now has been shaped and moulded by what’s gone on.”

Rennie 38, the former chief executive of a gay youth organisation, was responsible for “a colossal breach of trust”, Lord Bannatyne said at the High Court in Edinburgh. He had abused the boy — identified as Child F — almost from birth to the age of four years. He distributed images and films of his attacks to a gang of seven other men.

Strachan, 41, the only one of the gang with previous convictions for offences against children, was shown in background reports to display evidence of a psychopathic personality. One image that showed him abusing a baby left in his care displayed all his basest instincts, the judge said. “By its very nature what is shown in that photograph is utterly appalling and would shock to the core any right-minded person who has had to see it.”

Strachan was ordered to spend a minimum of 16 years in prison, while Rennie was sentenced to a minimum of 13 years.

Nearly 125,000 indecent images were seized during an 18-month police investigation, codenamed Operation Algebra. Six men were jailed in June for their involvement in the gang. All were respected members of the community, as was Rennie, and they included a civil servant, a bank clerk and a church bell-ringer.

The nine-week trial in the spring invoked conspiracy laws for the first time in a sexual offences case in Scotland, a precedent that prosecutors hope will have a profound effect on curtailing the making and distribution of images of child abuse by paedophiles.

“These offences involve real children and many of the photographs involve children being sexually abused, often in the most appalling ways. There are real victims of these offences, namely the children who were photographed and abused,” Lord Bannatyne said.

The judge reserved special praise for Detective Inspector Stuart Hood and the squad of 13 detectives who uncovered the gang.

Their investigations required an international operation that stretched from Lothian and Borders police headquarters at Fettes in Edinburgh and drew on the skills of Scottish and American academics, FBI agents and Microsoft personnel in San Jose, California.

As a direct result of Operation Algebra more than 60 individuals have been arrested in Britain, and according to police hundreds of offenders are believed to have been identified in Britain and around the world. Significant operations are continuing in central Scotland, Sussex, the Netherlands and the United States.

Strachan, convicted of eight charges in total, was also found guilty of repeatedly touching a six-year-old boy indecently. The jury found Rennie guilty of 14 charges, including one of procuring his best friend’s child for other men, an offer that Strachan took up.

The men — along with Ross Webber, 27, from North Berwick, Craig Boath, 24 from Dundee and John Milligan, 40, from Glasgow — were also found guilty of conspiring to gain access to a child or children to commit abuse.

After sentencing the mother of an 18-month-old boy abused by Strachan said that she would never be able to forgive him. “The anguish I feel towards Mr Strachan is indescribable,” she said.

“I feel that no matter what punishment is given to Mr Strachan, it will never be able to compensate for the hurt, devastation and great deal of stress brought to me and my family.”

Webber, Boath, and Milligan, along with Neil Campbell, 46, and John Murphy, 44, both from Glasgow, were sentenced to a total of 43 years in jail in June for their involvement in the paedophile ring.

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