Joseph Scholes died nine days into a two-year sentence

Joseph Scholes, from Sale, Greater Manchester, died at Stoke Heath YOI, Shropshire, in March 2002.

The inquest coroner called for a public inquiry, a request which has so far been resisted by the Home Office.

Support groups Inquest and Nacro held a parliamentary briefing on Tuesday to draw attention to the case.

The Commons meeting focused on the issues surrounding Joseph's death and the treatment of children in the criminal justice system.

Hundreds of questions have to be answered Yvonne Scholes

It also examined sentencing policy and the adequacy of procedures to protect vulnerable children in custody.

Co-director of Inquest Deborah Coles said: "This briefing follows the negative response from the Home Office to the call for the public inquiry.

"Since Joseph's death two more children have died. The public inquiry call is motivated by what is a serious human rights issue, the deaths and suffering of children at the hands of the state."

Joseph's mother Yvonne Scholes said: "When mothers hand over the care of their children to the state, they expect a role to be fulfilled.

"When a policeman knocks on your door and tells you your son has died whilst in the care of the state, hundreds of questions have to be answered. Only a public inquiry can answer these."

The inquest into Joseph's death heard how Mrs Scholes had contacted officials when he was sentenced to say her son had made a previous attempt on his life.

Joseph was nine days into a two-year term for taking part in mobile phone robberies when he died.

More than 100 MPs have signed an Early Day Motion in support of the call for a public inquiry.