In January, Judge Julian Hall, sitting at Oxford Crown Court, imposed a three-year supervision order on a 17-year-old boy who abused two young children, opting not to jail him because he did not believe him to be sufficiently dangerous.

The Solicitor General on Friday night confirmed the case had been referred to the Court of Appeal.

A spokeswoman for Vera Baird, Solicitor General for England and Wales, said that an interested party had asked for the sentence to be reviewed.

She said: "This case was referred to us and we have decided that it merits being referred on to the Court of Appeal. We are currently waiting for a hearing date."

Judge Hall caused outrage last June by jailing for just two years a man who raped a girl of 10.

After being referred to the Court of Appeal, the jail term imposed on window cleaner Keith Fenn, 24, was doubled after being deemed unduly lenient.

On Saturday Claude Knights, director of Kidscape, said of the latest case: "It's another disturbing judgment.

"We are quite worried about Judge Julian Hall. We now have a second child sex offence case involving a judge who has made some very disturbing decisions.

"It has been deemed to be out of line enough to be referred to the Court of Appeal and we would hope that justice will now be seen to be done."