A firearms officer killed himself after he became "obsessed" that his policewoman lover was seeing another policeman, an inquest heard.
Pc Nick Corless, 36, was found with a gunshot wound to his head in a grey Volkswagen Golf car parked in Brynn Street, St Helens, Merseyside, in February last year.
An inquest heard today that the policeman, who worked at Manchester Airport for Greater Manchester Police (GMP), killed himself because he feared losing his job after assaulting his lover, Anne Marie Greenall, who also worked for GMP.
Pc Corless left behind his widow Lisa and son, who was one at the time of his death.
According to the Whiston coroner, Dr Christopher Sumner, Pc Corless had grown suspicious that his lover was seeing another police officer called Lee Entwistle.
This suspicion had led to several episodes of violence during the weekend of his death.
Before recording a verdict of suicide, Mr Sumner said: "At the time of his death Mr Corless seemed besotted and obsessed with the thought that she (Anne Marie) was having a relationship with another man.
"There is certainly no doubt in my mind that he was carrying out an extramarital relationship with Anne Marie Greenall.
"On the weekend of the February 25, 26 and 27 last year there was an incident in which Nick Corless assaulted Anne Marie.
"In my mind, he thought that at best he would be referred to Greater Manchester Police's professional standards branch, and at worst he would face charges and imprisonment.
"Prison is not the best of places at any time, but it is certainly not an easy place for a police officer."
"It is clear that he intended to take his own life and therefore I can only record one verdict and that is suicide," he added.
The inquest heard that Pc Corless, a former soldier, and Pc Greenall had first started a relationship when they were posted with Merseyside Police at St Helens in 1999.
Detective Sergeant Eion Turner of Merseyside Police told the inquest that the relationship ended when Pc Corless went to London to join the Metropolitan Police, and there was no further contact between them until March 2010.
Although Pc Greenall had got married in 2008, the "spark" between her and Pc Corless was rekindled.
Pc Greenall told her husband she had been seeing Pc Corless in July 2010 and left him in August, he said.
A week before he died, Pc Corless also left his wife after spending his first Christmas with his then one-year-old son.
But throughout 2010 and into 2011, Pc Corless had grown increasingly jealous of another officer named Lee Entwistle, whom Pc Greenall had met at a murder scene in May 2009.
On the Friday before his death, Pc Corless and Pc Greenall returned from having drinks.
Pc Corless started stroking Pc Greenall, but she said she felt sick and did not want to have sex.
He said she described how Pc Corless "just lost it" and told her she would not reject Pc Entwistle, before straddling her and punching her in the face. The incident was not reported.
The following day, Pc Greenall went to her father's address and told him what had happened.
Some 50 minutes later a fight broke out on the doorstep between her father and Pc Corless.
Police were called and when they arrived they saw bruises on Pc Greenall's face and jaw from the previous night's assault.
Facing an investigation from Merseyside Police and a professional standards investigation by Greater Manchester Police over the matter, the following day Pc Corless killed himself outside Pc Greenall's home with a Beretta shotgun.
Inside the car, officers found a letter in which Pc Corless told Pc Greenall how sorry he was for attacking her although he could not remember what had happened, he said.
He also said he believed she was seeing someone, Lee, behind his back and his heart was broken.
He wrote: "I will be waiting for you in another life. I'm going to lose my job and go to prison. This is the only way I can go'."
A statement by Pc Corless's family was read out at the inquest describing him as a "loving family man who loved his job as a police officer, which was something he always wanted to do".
His widow Lisa also described him as a "loving" man and his commanding officer, Superintendent David Hull, talked of "an extremely well liked and respected colleague".
Need help? In the UK, call The Samaritans on 08457 90 90 90. For more support and advice, visit the website here.Suggest a correction