One of Scotland's longest-serving prisoners may have had his human rights breached, according to a judge.
Arthur Duncan was given a life term in 1970 for the rape and murder of a young woman in Hampshire.
Duncan, a prisoner at Glenochil near Stirling, is seeking damages from the Scottish Prison Service (SPS) and the Scottish Government with claims he has been deprived of a proper chance for rehabilitation.
The ex-serviceman says the alleged failure means he has not been able to satisfy the Parole Board that he is no longer a risk to the public and therefore suitable for release.
After considering the case at the Court of Session in Edinburgh, Lord Glennie said his case may constitute a breach of the European Convention on Human Rights but he will require a further hearing before making a ruling.
The judge said there was "no proper opportunity of access to any rehabilitation programmes" from April 2007 to July 2013 but added that his findings were provisional.
"I heard no evidence in explanation of why things had gone wrong in this way," he said.
"There may be explanations which satisfy me that there was in fact no breach of Article 5(1) or that any breach was more limited than at first appears."
Duncan, originally from Aberdeen, was convicted of murder on October 13 1970. His victim had been raped and strangled.
In 2002 the punishment part of his sentence was fixed at 10 years and his custody since then has been based on the need to protect the public.
Pornographic material including 30 video tapes were found in his cell at Noranside open prison in Angus in 2003 and he was transferred to Peterhead jail which had a specialist programme for sex offenders.
In 2007, explicit material was again recovered from his cell, including DVDs showing images of women being tied up and attacked.
The SPS is responsible for deciding which programmes are suitable for individual prisoners and ensuring they are available.