The couple had split four months prior after being together for more than 20 years.
While the 48-year old was married to the tannery worker, he was said to have been controlling and obsessive.
Hastings Police Senior Sergeant Bob Gordon, now retired, had known Ms Bower outside of his policing role. She had been living in a "heck of a controlling situation".
"He controlled her. He wouldn't let her have friends, didn't like her going out with her friends at work, basically he was the ultimate control freak and it was obviously a very dysfunctional relationship," he said.
This had begun to change after Ms Bower left the father of her two sons, Daniel and Matthew.
At her memorial service, Matthew said he had noticed a huge change in her, "as though that weight had been lifted".
"After we left home, she really came out of her little shell, she started to enjoy life a lot more, spending a lot of time with her friends and family. Going out for dinner and drinks, having a generally good time."
But as she emerged from her shell, her fear of Christison remained.
"She did everything she could"
In the months preceding her death, and with support from her sons and her employer - ANZ bank in Hastings - Ms Bower worked with agencies such as the police and Hastings Women's Refuge (HWR) to ensure her safety.
This began by informing police of exactly when she would be leaving Christison.
Although Mr Gordon had known Ms Bower quite closely, as his wife was her colleague at ANZ, he only became aware of the situation she was living in when she came to inform police of her planned separation.
"She came to tell me so basically the police would know on the day she was moving out, what she was doing, and where she was going in case he turned up and all hell broke loose," Mr Gordon said.
As family violence co-ordinator for the area at the time, Detective Sergeant Darren Pritchard knew to watch out for red flags. Although he never met Ms Bower, her situation and recent separation was brought to Mr Pritchard's attention.
"Along with her employer we collectively put things in place that included security guards at work, alarms at homes, and domestic violence protection orders, which Gail was granted."
When Ms Bower first got in touch with HWR, they also noted her situation fitted a lot of "red flag" criteria - from recent separation, possessiveness, stalking, threats to kill, an increase in frequency of violence.
Refuge manager Julie Hart said Ms Bower created safety plans for herself, and used her protection order wisely - by reporting whenever there were breaches, a picture was built of how dangerous her situation was.
"She had alerted neighbours to keep an eye out," Ms Hart said. "Part of her safety plan was to let friends and neighbours know what was going on so if they should see anything that it was ok to call 111."
Despite the protection order, Ms Bower's son saw his father's BMW drive past on multiple occasions.
After hanging around the property, Christison was served with a trespass notice by Mr Gordon.
"I found that he just wouldn't accept that he was the problem," Mr Gordon said. "He basically tried to blame everything on her and that's the type of character he is."
Mr Gordon said Ms Bowers had done everything she could, "short of her moving out of the country".
"He was the type of person who would just track her down, would go to lengths to track her down. She would have to have been hidden and her whole life would have had to have been turned upside down for her to be safe from him to be honest," he said.
During his trial, it emerged that Christison had told their son Matthew he would rather end up in prison, than let someone else be with his ex.
In a text sent a week after Ms Bower left their home, Christison told his son: "If I end up going to jail because of this then so be it but there is no way I am letting some else be with your mother".
He also wrote he was "about to lose the plot".
This was just months before 19-year-old Matthew found his mother's body in their backyard.
JUNE 7
In a defended facts hearing before Christison was sentenced for Ms Bower's murder, he gave evidence outlining the events of that day.
When his mother had visited him the afternoon of June 7, he had told her he had been having thoughts about harming his wife.
Christison's legal representative stated Christison had not intended to murder Ms Bower that night, but had gone to her property to scratch her car, and "lost it" after seeing her.
He drove his mother's car to the house that night, and parked it some distance away. He took with him leather gloves, a balaclava, and a hunting knife.
Once on Ms Bower's property, he scratched her car. He then tried to see her through a window. He watched her go out the back door, into the garden. She realised he was there, and shouted out to him.
She hit him over the head, and under the throat with a piece of wood. He launched at her.
He "woke up", next to the body of his wife who he had stabbed multiple times.
Christison told the hearing that after realising he had killed Ms Bower, he felt sorry for her, her family, and their children. He said he kneeled down and cuddled her body, wanting to die and go to heaven with her.
He placed a call to his mother after the attack.
"I've killed the bitch mummy, I've killed her."
When he was found by armed officers later that night, Christison had cuts to his throat and wrists, and was taken to Hawke's Bay hospital.
His first court appearance was on June 10, when he was charged with male assaults female in relation to her death.
By June 19 this charge had been upped to murder, and breach of a protection order.
After pleading guilty to her murder, on June 24 he was sentenced to life imprisonment with a minimum non-parole period of 17 years.
OFFENSIVE BEHAVIOUR
More than 300 people gathered at the Havelock North Community centre on June 13, 2013 to farewell Ms Bower.
As well as her family, friends, and colleagues, the agencies who had tried to prevent Christison harming Ms Bower were also affected, and were left questioning what more they could have done to prevent her death.
But while they had supported Ms Bower as she implemented plans, and took measures to ensure her safety, Christison not only did not change his violent behaviour, he had completely refused to acknowledge he had a problem.
Rather than focusing on what victims could do to be safe, Ms Hart said the emphasis needed to be placed on getting the offender to stop being violent.
"She had so much in place but he was highly motivated to punish her for leaving him," Ms Hart said.
"She was a great example of somebody who did their absolute best to protect themselves but when the violent person did absolutely nothing to change their violence it ended with her murder."
"Often people don't mind having a conversation with the victim like 'why don't you just leave?'" Ms Hart said. "But when does anyone have the conversation with the offender about 'why don't you just stop?".
Mr Gordon only had one dealing with Christison, but said he refused to accept that he was the problem.
"He turned everything around on her, he couldn't accept that he had an issue.
"At the end of the day, [offenders] have to accept in some ways that they need help. You can have court orders but to be honest they've really got to address their problems themselves and accept that they've got a problem."
Christison should have been seeking help, and those around him should have examined his mental state, Mr Gordon said.
If people witnessed such behaviour, and reported it to the police then more action could be taken to hold the offender accountable, or challenge them to change their behaviour.
Ms Hart said often after homicides, people would reveal the offender had mentioned worrying things to them, but they had not known how to deal with this.
"The challenge to the community is learn what to do. Find out what to do. Brothers need to address brothers, male work colleagues need to address male work colleagues and challenge them on their behaviour.
"Domestic violence is not ok but it is ok to get some help and there are agencies out there who work with the offenders but again the offender has to be willing to address their violence."
Although anger was a normal human emotion, Mr Pritchard said it was about how people dealt with their anger that affected loved ones.
"Gail was a loving, caring mother, daughter, sister, colleague, and friend that had her life ended in the most needless and selfish manner by someone that was supposed to love her."
