A MENTAL health patient who murdered a prostitute 17 years after killing his wife may not spend the rest of his life behind bars.

Judges at London's Criminal Appeal Court yesterday ruled that an order preventing George Leigers from ever being considered for release on licence was wrong.

At his trial last year, Leigers was told: "You pose such a threat that the public, and especially young women, must be protected from you, for the rest of your life."

But the Lord Chief Justice recently ruled only the seriousness of the crime should be considered when imposing minimum terms - not the protection of the public.

Yesterday, the Appeal Court ordered Leigers should serve a minimum of 21 years and 172 days before a decision is made on when, or if, to free him.

But Detective Inspector Gordon Lang, who put the killer behind bars, said last night: "If George Leigers is ever released, irrespective of his age, he represents a danger to the public.

"He has proven his capacity to kill twice already, and if parole ever becomes an issue, it is a big decision for anyone to make given what he has done in the past."

Last February, Leigers, 48, was found guilty of murdering 19-year-old Sarah-Jane Coughlan at his flat at Montrose Street, Middlesbrough, in August 2003.

After the killing, police found a personal organiser in his flat in which he had written: "Killed again... should have taken my medication."

In 1987, the father-of-three was convicted of the manslaughter of his wife, Rita, at their home in Blackhall, County Durham. He was sentenced to indefinite mental treatment after pleading diminished responsibility.

He was moved to a specialist nursing home six years later and released under supervision in 1997.

But in March 2003, doctors decided he no longer needed supervision.

Within five months, he struck again.

He took Ms Coughlan to his house for sex then stabbed her to death on his bed with a Second World War bayonet.

Leigers, now in the top security Rampton Hospital, Nottinghamshire, had stockpiled part of his medication.

When sentencing him at Teesside Crown Court, Judge Peter Fox ruled "life should mean life".

But Appeal Court Judge Findlay Baker yesterday concluded the judge was wrong to base his decision on the danger posed by Leigers.

Judge Baker acknowledged the manslaughter conviction and that the murder was "sadistic and brutal".

But, he noted, Leigers' mental disorder - which did not amount to diminished responsibility - should be taken into account.

Last night, the sister of Leigers' wife, who lives in County Durham, said: "It's shocking news. He should never be allowed out."

David Hines, of the North of England Victims Association, said the ruling was "absolute nonsense". He said: "If the judge at the trial said it should be life, it should be life."

Norman Brennan, director of the Victims of Crime Trust, said: "The sentence has to reflect the severity of the crime and this case just epitomises how the criminal justice system continues to fail victims."