PRESS ASSOCIATION -- The decision to halve the minimum jail term to be served by a "sickening and evil" rapist has been branded "completely at odds with what most people would describe as justice".

Robert Foye, who raped a schoolgirl while on the run from an open prison, was today told he would serve at least four-and-a-half years in prison before being considered for parole - half the original nine-year punishment.

The Court of Criminal Appeal in Edinburgh decided the punishment part of Foye's Order for Lifelong Restriction should be reduced because the original minimum term was "unsound in law and must therefore be discarded".

Judge Lord Osborne, who was sitting with Lords Woolman and Wheatley, said Foye would only be freed if the parole board were satisfied he no longer posed a threat to the public.

Following the judgment, Justice Secretary Kenny MacAskill said he would bring forward a proposed change in the law to address the issue.

Earlier this year, senior judges examining Foye's case and that of jailed paedophile Morris Petch issued fresh guidance on the approach judges should take when setting the minimum jail terms for people serving certain types of life sentence.

Foye attacked the 16-year-old in Cumbernauld, Lanarkshire, in 2007 and later admitted the attack when he appeared at the High Court in Glasgow.

He carried out the assault after being allowed out of Castle Huntly open prison near Dundee to attend an Alcoholics Anonymous meeting.

The serial offender was halfway through a sentence imposed for attempting to murder a policeman when he fled. He had been on the run for almost a week when he attacked the teenage girl.

In 2008, Judge Lady Smith ordered him to spend a minimum of nine years in prison and imposed a life-long restriction order on Foye, so that if he is released from jail he will be strictly supervised.