Yorkshire Ripper Peter Sutcliffe will learn the outcome of his plea not to have to spend the rest of his life behind bars.
A judge in the High Court in London will announce his decision on an application by the serial killer to have a minimum term set which will give him the chance of parole.
The 63-year-old former lorry driver, from Bradford, West Yorkshire, was convicted at the Old Bailey in 1981.
He received 20 life terms for the murder of 13 women and the attempted murder of seven others in Yorkshire and Greater Manchester.
A judge recommended that he serve a minimum of 30 years behind bars. He is currently being held in Broadmoor top security psychiatric hospital after being transferred from prison in 1984 suffering from paranoid schizophrenia.
Dr Kevin Murray, the psychiatrist who has been in charge of Sutcliffe's care since 2001, said in a 2006 report that he now posed a "low risk of reoffending".
Sutcliffe is said to have believed he was on a "mission from God" to kill prostitutes - although not all of his victims were sex workers - and was dubbed the Yorkshire Ripper because he mutilated their bodies using a hammer, a sharpened screwdriver and a knife.
