How did a distinguished Northamptonshire Police Officer become a murderer?

But just 18 months away from retirement, Goldsmith become one of the most notorious criminals in the county after he murdered his wife in a violent attack in which he battered her with a mallet, a paint pot and a torch battery.

For someone who was trained in restraint techniques and experienced in dealing with highly charged atmospheres, it seems inconceivable the 50-year-old lost his temper so badly he inflicted more than 70 injuries on his wife’s body.

However, after listening to Goldsmith’s evidence, which took almost two days, it was possible to gain some insight into how a police officer became a murderer.

Goldsmith, who had been married twice, met his third wife towards the end of 2011 after being introduced through a mutual friend.

He told the jury that this was the “happiest time of his life” and he described his relationship with Jill as a “fairytale romance”.

But on New Year’s Day 2012, the day Jill moved into his house in Wootton Hall, he said he was given the “devastating” news he was being investigated for misusing the police computer system.

Goldsmith said it “felt like being on death row” and caused the couple a great deal of stress and anxiety.

The court was also told about a dispute Goldsmith had with his neighbour who put in an official complaint about the noise of Jill’s son’s car exhaust.

After he had been given an official warning by Northamptonshire Police in September 2013, Goldsmith said he had a ferocious argument with his wife and he was then signed off work with stress.

Goldsmith went on to describe his honeymoon, during which he was frustrated by the fact they did not have sex, as a “disaster”.

In his opinion, a subsequent holiday in August 2014, when the couple were accompanied by Jill’s son Charlie, was also a “disaster” due to his wife’s heavy cannabis-smoking and menopausal symptoms.

By October 2014, Goldsmith said he was considering a divorce and he sent a furious text to Charlie threatening to throw him out of his house.

According to his evidence, the couple did live separately in December 2014 after another huge row about Christmas plans.

By February 2015, the jury was told that Goldsmith began to tape the rows he had with his wife and would check the milometer on his wife’s car to see how far she had driven. He even considered installing CCTV cameras in the house to monitor his wife.

Just one month before the murder, it was clear that Goldsmith was exhibiting an unhealthy, controlling obsession about her behaviour.

Giving evidence for the prosecution, Goldsmith’s son Michael, said his father saw his wife as a ‘project’ and wanted to change her.

The court also heard long letters and text message ‘essays’ Goldsmith wrote to his wife, in which he detailed her failings and bemoaned his own situation.

In one computer-typed, 23-page missive, he wrote that he was “ready to explode” and was “genuinely scared what happens when the switch gets flipped”.

He admitted that he had “scared Jill”, who he said was “increasingly concerned about my behaviour”.

Goldsmith’s irrational, overbearing behaviour ended with devastating consequences on March 26, a day of his annual leave during which he had intended to finish painting his porch.

Judge Paul Glenn, sentencing, said he rejected Goldsmith’s claim that his wife had become aggressive after smoking cannabis and attacked him.

Judge Glenn said he believed Goldsmith had not intended to kill his wife, who he believed he still loved.

But he said Goldsmith had carried out a “spontaneous” attack when he was in a “rage”.

It is clear that Goldsmith has been in denial about his actions on the day of his wife’s murder, consistently portraying himself as the victim during the trial even to the extent of faking stab injuries.

When he gave evidence, Goldsmith adopted the calm, calculated persona of a police officer describing a scene he had attended. Not one in which he was the main aggressor.

He also failed to show any regret or emotion when put under intense questioning during his cross-examination by John Lloyd-Jones QC.

At one point Mr Lloyd-Jones quoted Goldsmith’s own words from one of his letters to his wife in which he described himself as a ‘Jekyll and Hyde” character.

The barrister said the prosecution agreed with that analysis; on the one hand he was a decorated police officer on the other a violent murderer.

A jury also agreed with this analysis. It is time Goldsmith now faced up to the fact he has joined the ranks of the criminals he used to spend his working life protecting the public from.