O'Neill and Lauchlan appeal Allison McGarrigle murder conviction

O'Neill and Lauchlan are appealing their murder convictions

Two paedophiles who murdered a 39-year-old woman and dumped her body at sea are to challenge their convictions at the Supreme Court in London.

Charles O'Neill, 49, and William Lauchlan, 35, killed Allison McGarrigle in 1997 after she planned to report them for abusing a young boy.

After being convicted, O'Neill and Lauchlan were told to serve a minimum of 30 years and 26 years respectively.

Their appeals claim undue delay in the time it took to prosecute them.

Mrs McGarrigle met O'Neill and Lauchlan in 1994 after moving to Rothesay, Isle of Bute, following a split from her husband Robert.

She was introduced to them by the boy they went on to groom and abuse.

During a court hearing in 2010 it emerged that Mrs McGarrigle lived in fear of the men and had threatened to tell police about their abuse of the child.

She was last seen alive on 20 June 1997. Lauchlan and O'Neill are believed to have strangled her, put her body in a wheelie bin and dumped it at sea.

Allison McGarrigle's body has never been discovered

She was eventually reported missing by her estranged husband in 1998 and declared dead in 2005 when O'Neill and Lauchlan were charged with her murder.

They were released, however, after prosecutors decided not to go to trial at that stage.

The pair were eventually arrested - after several more instances of child abuse - during a police operation in 2008.

In May 2010, before the start of the trial, they were convicted of grooming a six-year-old boy having earlier sexually assaulted a 15-year-old boy while they were living in Spain.

O'Neill was also found guilty of drugging and sexually assaulting a 14-year-old boy in Irvine, Ayrshire.

After being given mandatory life terms for Mrs McGarrigle's murder, O'Neill and Lauchlan were also jailed for 10 years each for the sexual abuse charges.

'Not arguable'

Following conviction for murder, the pair launched appeals at the Court of Criminal Appeal in Edinburgh.

Judges rejected certain aspects of the proposed challenges, put forward as "not arguable".

But they have granted leave for O'Neill and Lauchlan to take part of their case to the Supreme Court.

This relates to the delay over prosecution, and in O'Neill's appeal, over a complaint about comments of the trial judge at the end of the first trial on the abuse charges.

William McVicar, solicitor advocate for Lauchlan, had argued that the trial judge erred in rejecting a human rights challenge against undue delay in the prosecution.

He maintained that the starting point in assessing whether or not it was done within a reasonable time began in 1998 when O'Neill was interviewed by police under caution on suspicion of conspiracy to murder.

The appeal court authority ruled that it started when an accused first appeared in court on petition, which would have been 2005.

O'Neill's solicitor, advocate John Carroll, had also argued that Lord Pentland appeared to lack impartiality at the later murder trial.

'Sexual predators'

At the end of the first trial, the judge described them as "dangerous and evil sexual predators of the worst kind".

He had then had to make decisions on challenges over the admissibility of evidence and on the fairness of the trial.

Mr Carroll also pointed out that Lord Pentland had rejected a move to adjourn proceedings to get medical help for O'Neill because of a severe headache while he was prepared to allow an adjournment when a police witness appeared to faint.

The appeal judges held that the delay point was not arguable but said they would allow it to be taken to London as "the issue raised is one which arises from statements in a decision of the Supreme Court on which that court may wish to provide further guidance".

Lord Hodge said they also adhered to the view that Mr Carroll's arguments over alleged prejudicial remarks and apparent bias by the trial judge were also not arguable.

But he said they would grant leave to appeal to the Supreme Court as they recognised that splitting the proceedings into two phases before different juries and the resulting presentation of previous convictions and the judge's remarks at the end of the first trial were "very unusual circumstances".

The judge said that if, as Mr Carroll had suggested, the Supreme Court had to adjudicate on all the challenges raised in the case to assess the fairness of the trial it "would significantly extend its jurisdiction in relation to Scottish criminal trials".