The mother murdered toddler James Bulger has challenged the Government to "stop protecting a criminal" after claims Jon Venables had committed a sexual assault.
Earlier this week the Prime Minister dismissed calls for transparency in the case saying he "would not comment" on the case while it was going through the legal system.
But Denise Fergus called on the Government to take legal steps to lift the anonymity Venables was granted when he was released on parole five years ago.
As the clamour for information grew Mr Brown said: "We cannot comment on individual cases that are going through the justice system, and I think the Justice Secretary explained the particular constraints in this case.'
But after the Sun newspaper published claims that Venables committed a sex assault a spokesman for Denise Fergus said the order granting her son's killer special protection should be scrapped.
Mother of three Denise, 42, said: "I do not want Gordon Brown or Jack Straw to comment on the case. I want them to take action to ensure that justice is done.
"They should stop protecting this man who is now adult criminal.
"Jack Straw should go to the High Court as Justice Secretary and get a judge to lift the Butler-Sloss order that shields Venables.
"If Venables has committed a sex assault he should be brought before a court under own name and be tried, in public, like anyone else.
"Breaching his parole should bee an end to the anonymity that he was granted on the excuse that he committed a murder as a child."
Denise said she was disappointed that Jack Straw had announced through the press that he would agree to her written request for a meeting.
She had a letter delivered to Mr Straw on Thursday but had received no response - not even an acknowledgement from Mr Straw or the Ministry of Justice.
Said Denise: "It feel insulted and angry that Jack Straw was not prepared to meet me until the press forced his hand.
"This conspiracy between the Government, the courts and a criminal is disgusting and an insult to justice.
"I feel so sorry for the victim in the case. It could be that she does not know his true identity.
"I don't want Venables put into a dock under a false name with a jury not knowing his background until after the trial is over.
"If Venables is going to be in court I want to be there to see justice done.
"He is not some kind of celebrity but that still the way they are treating him.
"If he has done a crime he should be tried as Jon Venables and if convicted he should go to jail as Jon Venables.
"I think he should then live the rest of his life under that name.
If he had been properly punished for murdering James perhaps this would not have happened. He would still be in jail and only now coming up for his first parole.
"I want all the facts in this case to come out. I suspect they have been covering-up pervious breaches of parole by Venables.
"The full truth must come out. He is a danger and he needs to be dealt with just the same as any other dangerous criminal."
Denise also expressed concern that the shroud of secrecy surrounding Venables could put other young jail inmates in jeopardy.
She added: "Any other 27-year-old who has gone into prison in the last week must be in danger.
"They are all going to be under the suspicion that they are Venables with the risks that carries.
"They could be attacked. This kind of problem has happened before and it is just not right that others prisoners should suffer in order to protect him."
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sarah., England around 10 months, 4 weeks ago