The family of murdered toddler James Bulger are challenging a court order which allows killer Jon Venables to live under a cloak of anonymity.
Jon Venables was 10 when he kidnapped, tortured and murdered two-year-old James Bulger, and he has been living under anonymity since his release from his life sentence.
The case will be heard by the most senior family judge in England and Wales, at the High Court on Tuesday, and could be held in open court.
It is understood the proceedings involve an application by members of the family to vary or discharge an injunction which “prevents identification of the person previously known as Jon Venables”.
James was murdered by 10-year-olds Venables and Robert Thompson after they snatched him from a shopping centre in Bootle, Merseyside, in February 1993.
Both Venables and Thompson were later granted lifelong anonymity by a High Court judge.
Following release they have lived under new identities.
But Venables has since been convicted and sent back to jail over indecent images of children.
In February, he was jailed for three years and four months after admitting surfing the dark web for extreme child abuse images and possessing a “sickening” paedophile manual.
He was charged after police found more than 1,000 indecent images on his computer.
It was the second time he had been caught with such images and when he was arrested he told police he was plagued by “stupid urges”.
James’s mother, Denise Fergus, and father, Ralph Bulger, attended the Old Bailey when Venables was sentenced in February.
Mrs Fergus said on Tuesday that she is not involved in the High Court proceedings before Sir James Munby.
In a statement she said: “I understand the motivation for the application, but my concern is that if Venables were known by his own name, it could lead to vigilante action and innocent people being hurt.
"Beyond that, I have no further comment to make.”