POLICE who investigated the latest killing to be carried out by David Collins have told of their relief that he will spend decades behind bars.

Collins has a history of violence but even experienced officers were left shocked by the brutality he displayed when murdering 32-year-old Kevin Bishop and chopping up his corpse.

That savage killing took place 16 years after Collins had stabbed his abusive father, also named David, to death with an ornamental sword at the family home in Kilbarchan.

READ MORE: David Collins: Crazed killer found guilty of murdering Kevin Bishop and chopping up his body

Collins, of Shuttle Street, was aged 30 in July 2002 when his fractured relationship with his 50-year-old dad came to a bloody end.

He was initially charged with murder but pleaded guilty to the lesser offence of culpable homicide at the High Court in Paisley.

The court was told Collins and his three siblings had been subjected to decades of physical and emotional abuse.

The Gazette: Kevin Bishop met a brutal end Kevin Bishop met a brutal end

On July 20, 2002, Collins got into a heated argument with his brother, which led to them being confronted by their dad, who was brandishing a crowbar.

After being struck a number of times by his father, Collins grabbed an ornamental sword and both men went outside to the garden.

In the moments that followed, Collins lunged at his dad with the sword, stabbing him in the upper arm and chest.

Defence counsel Donald Findlay QC urged judge Lord Carloway to show compassion in dealing with his client, whom he described as being a victim as much as an accused.

However, Lord Carloway said the history of provocation and violence on the part of Mr Collins senior had to be balanced against the fact his son had a significant criminal record involving violence.

Collins was caged for five years.

And any hope that he would turn his back on violence after being released from prison proved to be forlorn.

By July last year, Collins was living in Schaw Road, in the Gallowhill area of Paisley, where dad-of-two Mr Bishop met a truly horrific death as he was attacked with a machete.

The next day, Collins cut off his victim’s head before severing his arms and legs.

Mr Bishop’s torso was discovered dumped in a wheelie bin outside the flat several days later but his head and limbs were never found.

Collins, 46, told jurors he had been acting in self-defence at the time of the attack but, on Friday, was found guilty of murder and attempting to defeat the ends of justice following a trial at the High Court in Glasgow.

It emerged he had effectively confessed to his ex-partner Anne Melville, telling her there had been a confrontation and that “Kevin died.”

READ MORE: David Collins: Killer caged for 26 years for chopping up Kevin Bishop's body

Miss Melville went on to ask him: “What are you going to do? Fire him in a wheelie bin?”

But callous Collins insisted his victim’s body parts were “already away.”

Despite what he said, Miss Melville told jurors she did not believe her ex.

The mum later went to Collins’ flat with their daughter to give him a birthday present.

Miss Melville also brought with her a suitcase that belonged to him.

Collins took it into a bedroom and came back out sweating heavily.

Miss Melville recalled going in at one point and there was “something on the floor, wrapped in plastic.”

She told the court: “He lifted it and put in the suitcase.”

Miss Ross asked her: “Did you question him as to what he was doing?”

She replied: “No.”

The trio then went outside and Collins had the case with him.

Miss Melville said: “He put it in the bin...it looked heavy.”

Collins then poured a bottle of aftershave on top to mask any smell that might emerge.

But his former partner insisted: “I did not know what to do. I thought I will wait and see if the guy turns up.”

The trial was told the cause of Mr Bishop’s death could not be confirmed.

While giving evidence in his own defence, Collins claimed Mr Bishop had come at him first with a knife and he only swung the machete to “scare” him off.

The Gazette: DCI Martin Fergus DCI Martin Fergus

Collins told the court it took just five minutes to hack off his victim’s head and around an hour to remove his limbs.

Detective Chief Inspector Martin Fergus, from Police Scotland’s Major Investigations Team, branded Collins “a very dangerous and callous individual.”

He said: “It is a relief that he has been taken out of our community and will no longer be free to harm others.”

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