The savagery and sadism involved in the murder of teenager Barry Wallace still has the capacity of shock more than two decades later.

Call centre worker William Beggs handcuffed Barry's hands and legs in his flat in Kilmarnock before sexually assaulting the 18-year-old. Once dead, Beggs dismembered Barry in his flat. 

He then disposed of the arms, legs and torso in Loch Lomond and dumped the head from the Troon to Belfast ferry before it washed up on Barassie beach in Ayrshire.

As the net closed in, Beggs went on the run for a year and was eventually arrested in Amsterdam.

After a year of legal wrangling he was extradited back to Scotland where he stood trial at the High Court in Edinburgh in September, 2001 where he was later found guilty of murder.

Beggs was given a life sentence and told he must serve at least 20 years before he can be considered for parole.

That term was backdated to the time of his arrest in Holland in late 1999 which means he has been eligible for parole for the last three years.

However at present there are no signs of him being released from prison any time soon.

Today the Herald puts William Beggs under the microscope and asks the question: will he ever be released and can there ever be a justification for doing so?

The Herald: BARRY WALLACE FAMILY PRESS CONFERENCE,  PITT STREET POLICE STATION...PIC OF..... COLLECT PICTURE OF WILLIAM BEGGS.....PICTURE BY CHRIS JAMES. (32670158)

Beggs was one of five children brought up in the village of Moira, near Lisburn in Northern Ireland and educated at a Quaker School.

He was involved right-wing politics in his teens including the Democratic Unionist Party led by the Rev Ian Paisley.

As a student at Teesside Polytechnic in Middlesbrough he rose to become regional chairman of the Federation of Conservative Students. 

This led to him being invited to a Burns Supper at Downing Street while Margaret Thatcher was Prime Minister.

In May 1987, the mutilated remains of a young man were found by a gamekeeper near Cleveland Forest in north-east England.

The victim was 28-year-old student Barry Oldham from Bolton who had been previously living in Aberdeen. 

His throat had been cut and attempts had been made to dismember his body at the elbows, knees and neck.

Barry had travelled to Newcastle to meet Beggs and the pair appeared to have had a short relationship.

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Within a month Beggs had been arrested and charged with the murder. He claimed he'd acted in self-defence after Barry had attacked him during a camping trip on the North York Moors.

Beggs was found guilty and sentenced to life imprisonment. 

Two years later his conviction was overturned on appeal - after the trial judge had allowed allegations of previous attacks on men by Beggs to be heard by the jury. 

It meant that Beggs was a free man to strike again, not only once but twice.

Following his release Beggs move to Kilmarnock where he got a job as a housing officer with the local council.

He met a church worker Brian McQuillan in Bennetts nightclub in Glasgow in July 1991.

Brian, who was also from Ayrshire, agreed to go back to Beggs flat in Kilmarnock where he attacked him with a razor. 

The Herald: Kilmarnock town centreKilmarnock town centre (Image: Newsquest Media Group)

The terrified 28-year-old escaped by leaping naked through a first-floor window on to the ground where neighbours found him.

Beggs was jailed for six years and sent to the State Hospital at Carstairs in Lanarkshire for assessment, to see whether he needed psychiatric treatment.

Doctors concluded he didn't and was instead sent to prison, where he served three years.

After his release Beggs studied at Paisley University and later became a lecturer in computer technology.

His final victim Barry Wallace was working as a Tesco supermarket shelf-stacker and considering a career in the Royal Navy.

On the evening of December 5, 1999, he joined colleagues for the store's Christmas party and was last seen near a taxi rank in Kilmarnock around 1.45am the following morning.

Beggs, then 36, had just finished his shift at an Edinburgh call centre and was returning to his flat when he spotted Barry.

Unaware of any impending danger, the teenager accepted a lift from Beggs despite never having met him before.

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It's thought the terrified teenager died during the vicious assault in his assailant's first floor flat a short time later.

As police began their investigation into Barry's disappearance, Beggs acted as if nothing had happened and even attended his office Christmas party in Edinburgh.

A friend of Beggs would later recall how he had phoned the killer hours after the murder and could hear he was driving. Beggs said he had 'got off' with a 'sweet, cute guy' the night before.

When the missing person inquiry turned into a murder investigation Beggs became a prime suspect because of his history of attacks on young men, including Brian McQuillan

Shortly before Christmas, police obtained a search warrant for Beggs's Kilmarnock flat where they found an array of incriminating forensic evidence linking him to Barry's murder.

But this time Beggs had fled the country via Jersey and France.

The Herald: Limbs were discovered in Loch LomondLimbs were discovered in Loch Lomond

His photograph was then released to the public and police forces across Europe.

On December 28 he walked into a police station in Amsterdam and surrendered to the authorities.

It would be another year before Beggs was handed over to Scottish police to stand trial for Barry's murder.

In an interview following his conviction in 2001, Brian McQuillan revealed how he believed Beggs drugged him before carrying out the attack.

He said: "I woke up with this incredible pain. I was lying on my back and he had pushed my left leg up in the air towards my shoulder and I actually thought he was biting the top of my leg. 

"There was blood everywhere. I grabbed his hair and pushed his face away. I jumped up and ran to the door to escape but he chased me. 

"The look in his eyes is something I will never forget. He was completely demented - something had snapped in his head. 

"I just feel so sorry for Barry Wallace's family because I always knew Beggs would murder again. 

"But this time they must cage this monster for the rest of his life. If released, he'll kill again."

It's not known if Beggs has ever shown any remorse for Barry's murder, which would be a prerequisite for getting parole.

Over the years one man has had no doubt that Beggs should remain behind bars.

Detective Chief Superintendent Tony Fitzgerald, former head of North Yorkshire CID, led a team of more than 100 officers on the Barry Oldham murder inquiry in 1987. 

In one interview he said: "When we caught Beggs all those years ago, we seriously thought we had caught a serial killer in the making. 

"We thought we were lucky because we had managed to catch him after his first killing.

"God only knows how many people he has actually hurt over the years.

"Beggs was a cold, dangerous individual who was concerned only with his own satisfaction from inflicting pain on people. We were concerned at the time that Beggs would carry on in the same way after being freed."

In 2011 Barry Oldham's elderly father Albert wrote to the Crown Prosecution Service in England to ask that Beggs be retried for the 1987 murder, 

At the time the law in England had been changed - as in Scotland - to allow accused persons to stand trial for the same crime twice. 

Mr Oldham, then 81, said: "I don't know how long I've got left. 

"I'd like to know he was going to be punished for what I believe he did to my son."  

Since his conviction for killing Barry, Beggs, now 59, has become a serial litigant raising countless actions in the Scottish courts estimated to have cost more than £1million in legal aid.

Some have been against the Scottish Prison Service over his treatment behind bars, others to appeal his conviction for the murder of Barry Wallace.

In March this year Beggs, who represented himself, lost a case at the Court of Session in Edinburgh for further legal aid to help launch a fresh appeal. 

Robert Black, Emeritus Professor of Scots Law at Edinburgh University, says this suggests Beggs is not looking for parole but still believes that his conviction can be overturned.

He told the Herald: "Parole is not automatically granted just because the 20 years has elapsed.

"If he does make an application the parole board is obliged to consider it.

"But they don't have to grant it.

"The parole board will look at whether Beggs recognises his own guilt.

"If he is still considered a danger to the public, then his chances of getting parole are virtually nil."

Professor Black says it is possible that Beggs now believes that he may never get parole.

He added: "If his position is that he was wrongly convicted, then he may have decided it is pointless to apply for parole.

"He may feel that the best route out of prison is through the appeal process.

"But he would have  come up with new evidence or evidence that was not available at the time for this to happen."

Five years ago Barry's father Ian, then 67, urged the Scottish Government not to free Beggs.

He added: "Any parent who loses a child can never get over it.

"The world will be a safer place if Beggs dies behind bars."