A KILLER who cultivated an “obsessive hatred” of his ex-wife’s new lover is facing a life sentence for murdering a “true gentleman” in a brutal knife attack.

Paul Smith, 43, plunged a blade deep into the throat of Andrew McCarron, 49, following an altercation in Lochend Road South, Edinburgh, on July 21, 2019.

The High Court in Edinburgh heard how months earlier Mr McCarron’s family member - a man called Jamie Bell - started dating Smith’s former wife, Nicola Johnstone.

The court heard how Smith nursed a grudge towards Mr Bell, whose mother Catherine, 52, was engaged to Mr McCarron.

In the months leading up to the attack, Smith sent a series of text messages to Nicola in which he threatened to kill Mr Bell.

On the night of the fatal incident, Smith armed himself with a large knife and went to visit Edinburgh City FC’s social club where members of the Bell family were enjoying a night out. 

Mr McCarron tried to stop the situation from escalating into trouble. But Smith rammed the blade 15.5 centimetres - more than six inches - into his throat. Doctors fought to keep Mr McCarron alive.

But he later lost his fight to stay alive.

The story emerged following the end of a three day trial at the High Court in Edinburgh.

Smith, also of Edinburgh, admitted stabbing Mr McCarron but denied murdering him.

Smith’s lawyer Brian Gilfedder told jurors that evidence in the case showed his client was guilty of the lesser crime of culpable homicide.

However, jurors found him guilty on a charge of murder. Judge Lord Burns remanded Smith in custody ahead of a sentencing hearing next week.

He told him that he would be imposing a life sentence on him. Lord Burns added: “There is only one sentence which I can impose in this case.

“Before I can proceed I have to determine what is known as the punishment part of the sentence - that is to say the time in prison you will have to serve before you are eligible to apply for parole.

“I will therefore adjourn sentence for a period of one week and you will be remanded in custody.”

Mr McCarron worked as an electrician for an Edinburgh-based company called David Love Property.

The firm owns and rents private homes and commercial properties in Edinburgh, Fife, Aberdeen and Tenerife.

In a Facebook post following the attack, Mr Love wrote: “I received a devastating phone call this morning. My good friend and irreplaceable employee Andy McCarron was murdered last night. He was a true gentleman. I hope karma acts fast. RIP Andy.”

The court heard that Mr McCarron was originally from Birmingham. During proceedings, the court heard Ms Johnstone say she split from Smith in February 2019. She started a relationship with Mr Bell.

She told prosecution lawyer Lisa Gillespie QC that Smith started threatening Jamie Bell on a weekly basis.

When Ms Gillespie asked her about the nature of the threats, Ms Johnstone replied: “All manner of things. He would chop his b**** off.

“He was going to kill him basically. He was going to harm Jamie.”

The court heard that Smith also sent Ms Johnstone a series of text messages in which he threatened Mr Bell and insulted him.

One of the messages read: “You decided s******g a f****** inarticulate, skinny wee ugly s****** was the way forward.”

She said that Smith started drinking heavily after she left him. She eventually sent him a message telling him: “Done with you. You are just a nasty wee man.”

The court also heard that Smith also spoke of his dislike of Mr Bell to acquaintances. Lord Burns deferred sentence in order for Mr McCarron’s family to prepare victim impact statements.

Smith will be sentenced at the High Court in Edinburgh on October 29.