An obsessed former police officer who caught his wife having sex with a married colleague in a car park has narrowly avoided jail after being convicted of stalking.

Gavin Harper, 45, found Stephanie Glynn, 40, and her lover Andrew McLullich, 42, outside the hardware store in Birkenhead, Merseyside, UK on February 16, 2021, after secretly placing a tracker on his wife’s car.

He slowly crept up to the vehicle and used his mobile phone to record the lovers, who were naked from the waist down, before allegedly shouting: ‘I’ve got you on film sh***ing my wife.’

The dad-of-two was found guilty of aggravated stalking, including secretly bugging Ms Glynn’s car, listening to her conservations, tracking her movements and taking her phone without permission.

He was also accused of assaulting Mr McLullich, a Merseyside Police Inspector, but was cleared of injuring the officer at Liverpool Crown Court as he claimed he only struck the policeman in self-defence.

Prosecutors said it was Harper’s conviction was the end of the campaign of ‘obsessive, intrusive and unwanted behaviour’ against Ms Glynn from December 2020 to February 2021.

Harper and Ms Glynn met as Merseyside Police officers and were in a six-year relationship before they married in 2018 but she left the family home in December 2020 after she grew close to her work mentor Mr McLullich, an acting inspector at the time and formerly her supervising sergeant.

Giving evidence, Harper said he wanted ‘undeniable proof’ of the affair, which he said Ms Glynn had persistently denied.

His intention was to pass the video to police as evidence of two serving officers having an inappropriate relationship during Covid lockdown restrictions, he said.

On Monday, Judge David Potter sentenced Harper to two years in jail, suspended for two years.

The judge told him he would have faced immediate custody but for the significant effect that imprisonment would have had on his elderly parents and youngest son

Harper’s lawyers told the court that he would lose his security job if jailed and would be unable to make his mortgage payments. His parents, whom he informally cared for, would ‘not be able to cope’ and his son would have to give up his university studies.

Judge Potter told Harper: 

‘I am sure you became obsessed to the point of criminality in stalking Stephanie Glynn to provide evidence of her affair to weaponise that against her for having that affair, and you also became determined to destroy the career of Andrew McCulloch.

‘In that obsession the feelings, embarrassment and pain felt by Stephanie Glynn were collateral damage. You were more concerned about your own feelings and a raging sense of injustice.’

He said the events at Screwfix ‘do no credit to any of the people involved’ and the incident was ‘rash, foolish, selfish and unprofessional’.

Judge Potter went on:

 ‘I am sure it has haunted them (Ms Glynn and Mr McLullich) and will continue to haunt them for many years.’

But he said their acts were ‘made worse’ by Harper filming them on his mobile phone.

He said: ‘It was a further gross example of stalking designed to maximise their humiliation to your advantage. Your conduct was intended to maximise fear or distress.

‘You resorted to stalking out of a sense of vengeance for being the victim of an affair. I am sure the distress caused to your victim has been very serious.’

But he added that there was ‘another side’ to the defendant who had no previous convictions, and had suffered mental trauma himself.

Harper had been diagnosed with post-traumatic stress disorder as a result of his Army service in the King’s Regiment and the Royal Military Police – before he joined Merseyside Police in 2001.