A former prison officer from Bushey led a double life as a paedophile photographing and filming years of child abuse, including the rape of a four month old baby.

John Maber, 47, was caught out after police intercepted an internet conversation where he offered to abuse a child over a webcam for another paedophile, a court heard.

This led officers to Maber’s address where his computer equipment revealed images and videos he had made of his abuse and shared with other paedophiles over the internet.

At a hearing at St Albans Crown Court in May he admitted 27 counts including child sex abuse of as well as owning and distributing child sex images and videos.

Today at Maber’s sentencing Judge Marie Catterson told him:"The rapes of [a baby] aged four and a half months which you have admitted represent abhorrent behaviour of the utmost conceivable gravity, and contrary to every normal human instinct."

The court heard officers from Hertfordshire Constabulary were at Maber’s door, in Oundle Avenue, within hours of being alerted about this webchat by New Zealand police on Friday December 2. After his arrest Maber initially told police the conversation had been a joke and gave a no comment interview.

However after police seized Maber’s laptop, hard drive and iPhone, they uncovered the digital record of his depraved activities.

Among the pictures and videos were some of him abusing a child under five and one where a child had their mouth gaffer taped.

Police also found internet chat logs where Maber had shared some of the images of his abuse with other paedophiles.

The judge was told the police investigations led them to later seize a second hard drive, which contained pictures Maber had taken of himself committing his most serious abuse, including the rape of a small baby.

Other images from that hard drive showed him abusing a toddler a young as two years old.

A Motorola phone also seized in the second swoop and revealed Maber had had extensive text conversations with other paedophiles, discussing abuse of children.

The court was told that some of the abuse was committed at Maber’s father’s house in Corbin’s Lane, in South Harrow, as well as at the Bushey address.

Maber’s computer equipment also contained 134 images of extreme pornography involving animals.

The court heard that after being bailed from his initial arrest, Maber made some admissions about his abuse to his girlfriend and on Monday December 5 took an overdose of Paracetamol.

Following his overdose Maber was taken into psychiatric care, where he made further admissions about his sex abuse of children.

However in the end he only pleaded guilty to what the police could prove from his computer equipment.

Christopher Strachan, defending Maber, said his client had a clean criminal record until his arrest and had been a prison guard for 18 years.

At the time of his arrest Maber was working at Pentonville Prison in London and had been a senior officer in charge of two wings.

Mr Strachan said his client had also pleaded guilty to the charges at the earliest opportunity.

He added: "In a sex case as horrific as this it can serve as no justification, but should be taken into account.

"My submission is that offending of this nature is almost beyond comprehension to the normal civilised mind."

Before passing sentence Judge Catterson told Maber that his depraved behaviour amounted to sex addiction.

She said: "All that you did for your own perverted sexual gratification, without the slightest regard for the welfare of [the child]. You used the depraved images you had taken of your abuse online to further your standing with others of similarly perverted mindset.

"I have had the opportunity to observe you on several court appearances. I do not doubt that you are shamed, perhaps even mortified, by the position in which you now find yourself.

"That may be a small step in the right direction; but given the nature of this offending it is a small step on a very long road."

The judge handed Maber a life sentences with minimum of 20 years, which means he will not be able to apply for parole for at least nine years.

Maber, who wore a polo shirt in the dock, stared at the ground throughout the court hearing and appeared unmoved as he heard his sentence.

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