Venables was given lifelong anonymity when he was released in 2001
The mother of murdered British toddler James Bulger has accused the authorities there of "colluding" to cover up his killer's behaviour after he was sent back to prison again.
Jon Venables, who was given lifelong anonymity with a new identity when he was released on licence in 2001, has been jailed after admitting possessing more than 1,000 indecent images of children and a paedophile manual.
Mr Justice Edis described the pictures as "vile" and "heartbreaking", adding that many showed abuse of young boys like James.
Police found a total of 1,170 indecent images: 392 judged to be in category A (the most serious), 148 from category B and 630 from category C.
Venables, who was sent back to prison in November after he was caught with the pictures, appeared via video link from custody during the hearing at the Old Bailey in London.
He was sentenced to three years and four months in prison, with James' parents Denise Fergus and Ralph Bulger present in the court.
Chris Johnson, a spokesman for Ms Fergus, branded the sentence a "farce" and said Venables would feel like he had "got away with it".
He accused the authorities of colluding to cover up Venable's behaviour and called for a public inquiry into the case.
Mr Johnson said the disclosure in court that Venables was issued with a caution in 2015 when he gained access to the internet was "part of a pattern of collusion between Venables and the authorities".
This is the second time Venables has been caught with such material, having been jailed for two years in 2010 after admitting charges of downloading and distributing child abuse images.
The court heard that the latest images were of children mainly aged between six and 13, although some were younger.
Police found a paedophile manual, aimed at teaching abusers how to have sex with children "safely".
Prosecutor Louis Mably QC told the court: "The manual is a disgusting and sickening document which falls far below any recognisable standard of morality."
Mr Mably told the Old Bailey that Venables had software on his computer to browse the dark web and admitted downloading the material from there.
A report had found that Venables was a "high risk of real harm to children in the future" and has a "long-term and profound interest in children", the court heard.
Mitigating, Edward Fitzgerald QC said: "He has asked me to apologise to all those he has let down. He apologises to the family of James Bulger for the renewed distress he has caused by his renewed offending."
Venables and his classmate Robert Thompson abducted, tortured and killed two-year-old James in Merseyside in 1993 when they were both aged 10.
Venables was released after serving eight years for the murder and has breached the terms of his licence numerous times since.
As well as being caught with abuse images in 2010, Venables was given a formal warning after being arrested on suspicion of affray following a drunken brawl in 2008 and cautioned for possession of cocaine that same year.
Mr Fitzgerald told the court Venables' latest "relapse" had been swiftly detected, adding: "Jon Venables still has the capacity for good and a capacity to change."
Sentencing Venables, Mr Justice Edis told him the images he downloaded were "heartbreaking for any ordinary person to see this kind of material".
He described the manual as a "vile document" and told Venables that, as a consumer of these "products of barbarous evil", he in turn caused it to happen.
The judge added that the offences Venables committed while on licence showed he was a "manipulative and dishonest" man.
As well as his prison sentence, Venables was also made the subject of a sexual harm prevention order and Mr Justice Edis ordered that his laptop be taken away.