It was March 7, 2002 and the gunman had walked into the housing estate in Acacia Way, Cambuslang on the outskirts of Glasgow shortly before 10pm.

The development had attracted large numbers of upwardly mobile families looking for somewhere new, safe and modern to bring up their families.

His target was 30-year-old businessman Justin McAlroy who was about to become a dad.

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Glasgow Times:

Justin had just arrived home that night and as he stepped out of his car the gunman fired six shots. Five hit the victim in the arm, leg, chest, and head who fell to the ground.

Justin's body was discovered by his shocked and pregnant wife Tracey.

An ambulance was called but he died in the early hours of the morning at Glasgow's Victoria infirmary.

The killer left Acacia Way on foot, and ran along a pathway to Newton Station Road where he entered the passenger seat of a waiting white getaway car.

The car drove off in the direction of the M74 which would eventually lead to Easterhouse, Glasgow.

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Glasgow Times:

Shortly before 11pm a white Saab was found abandoned and set on fire in Balcurvie Road, Easterhouse.

Various items abandoned included gloves, a black jacket with a hood, a dark grey woollen scarf or snood, a Yazoo brand drinks bottle and a radio scanner.

The scanner was still switched on, operating and tuned to the police wavelength, thus enabling police communications to be listened to.

A telephone call had also been made from a mobile phone near the spot where the car had been dumped around the time it was set on fire.

It appeared that this was the getaway vehicle that the police had found.

But who had been inside it and what was the motive for the murder?

Glasgow Times:

It was clear that the killer had been lying in wait for his victim and it was a targeted attack.

Local residents were shocked that one of their neighbours had been shot dead in an area where people had moved for a better quality of life.

It then emerged Jason McAlroy had been leading a double life and may have been targeted over a £50,000 drugs debt.

He had also been under surveillance by the Scottish Drugs Enforcement Agency for more than a year before his death.

Now disbanded the organisation was then responsible for investigating peoples alleged involvement in serious and organised crime, particularly the multi million pound trade in hard drugs Clearly Justin was a man with contacts and enemies in the criminal world but which one had he crossed?

Glasgow Times:

A suspect emerged early in the inquiries a 38 year old car dealer from Hillhead, Glasgow William Gage.

He was eventually charged with the murder on May 3 - eight weeks later- and strongly protested his innocence.

Gage had some knowledge of guns having been a former member of the Territorial army but he issued that was his last ever involvement.

He said that he knew nothing about the clothing found in the car and could not understand how his DNA was on it.

In February 9, 2004, he was convicted after three week trial in the High Court at Glasgow The jury's verdict of guilty of murder was by a majority.

Gage was sentenced to life imprisonment with a punishment part of twenty years, for he can apply for parole.

Since his conviction 18 years ago Gage has launched several appeals claiming there has been a miscarriage of justice His first appeal was refused in 2006.

The Scottish Criminal Cases Review Commission subsequently referred his case to the appeal courts which was heard by five judges in Edinburgh in 2012. But they upheld the conviction.

The evidence presented during the trial had appeared to be compelling.

Forensic experts had discovered that DNA found on the neck of the Yazoo bottle matched Gage's.

DNA from the gloves and the snood also matched his DNA profile as did swabs from the hood and jacket.

A second forensic examination discovered firearm residue on the jacket and the snood.

The jurors were told that the firearm discharge residues found on the snood and the jacket were of a similar type to the residues found on items at the location of the shooting.

The phone used around the time the getaway vehicle was abandoned, matched numbers found by murder squad detectives in a search of the flat in Byres Road where Gage lived.

Though there were not witnesses to the actual shooting a number of people had seen the getaway and got a glimpse of the gunman, including the victim's wife.

Two of the witnesses, a man and a 15-year-old girl, had been travelling on Newton Station Road at about 10.00pm, They noticed the white vehicle parked there with someone in the driver's seat.

As their car was passing they saw a masked figure run down the gravel path leading from the murder scene on to Newton Station Road and enter the front passenger seat before driving off. Coincidentally it turned out that the girl knew the victim and saw the running man remove the mask once in the car.

She noticed that he had a chubby face and a rounded head and was wearing a padded jacket Clearly they had seen the killer during his getaway.

The clothing worn by the killer was also observed by several other witnesses, including Tracey.

She had been alerted by two or three very loud noises, like a car back-firing, coming from the front of her house. She went to investigate. She saw a man under a street lamp running away. He looked at Mrs McAlroy as he ran in the direction of Newton Station Road.

Only from his forehead down to the bottom of his nose was visible.

She was later taken to Aikenhead Road Police Station in Glasgow where she was shown a tailors dummy dressed in the clothing recovered from the Saab.

In evidence she said that she recognised the clothing on the mannequin as the clothing worn by the man she had seen under the street lamp following the shooting of her husband.

Two neighbours in Acacia Way also gave evidence at the trial.

They spoke about the sound of gunfire around 10pm and seeing a man running away One was shown the jacket recovered from the Saab by the police and she had said it resembled the jacket he was wearing. There was no real dispute at the trial that each of Mrs McAlroy and the two women had seen the killer.

Mrs McAlroy later pointed Gage out in the dock as resembling the gunman.

On being asked how sure she could be of the resemblance, she responded: "It's just I'm not 100% sure, I've got a vision, I've got a picture of his eyes". She described them as "scary eyes".

Gage however claimed that his girlfriend had been with him at the time of the shooting in the West End of Glasgow and had remained in her company until about 11.00pm.

However he was found guilty after the jury was shown records of mobile phone calls that discredited the girlfriend alibi.

Over the years Gage's legal team lawyers argued that he did not get a fair trial and was the victim of mistaken identity.

They challenged claims that the Saab car, said to be the a getaway vehicle, was actually used in the shooting They pointed out that there was no CCTV footage showing the car travelling between the murder scene and Easterhouse as might have been expected.

They also said too much weight had been placed on the identification of the accused in the dock by the victim's wife.

They further argued there were "substantial inconsistencies" in the clothing evidence which had linked Gage to the shooting.

John McManus of the Miscarriages Of Justice Organisation said at the time of the murder accused: "He's no angel but he's no murderer."

However judge Hamilton, sitting with Lords Reed, Carloway, Mackay and Nimmo Smith, in Edinburgh rejected his appeal and said they had not been persuaded that the trial was unfair.

In a writer judgement they added: "Criticisms can undoubtedly be made of the evidence in each of these strands but, when the evidence is looked at as a whole, the case against the appellant was, in our view, compelling."