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Men who kill their partners follow a "homicide timeline" that could be tracked by police to help prevent deaths, new research suggests.

Criminology expert Dr Jane Monckton Smith found an eight-stage pattern in 372 killings in the UK.

The University of Gloucestershire lecturer said controlling behaviour could be a key indicator of someone's potential to kill their partner.

One murder victim's father said the findings could help to "save lives".

About 30,000 women across the world were killed by current or former partners in 2017.

Dr Monckton Smith said women account for more than 80% of victims killed by their partners - and most of the time, the partner is male.

To conduct her study, she looked at all cases on the Counting Dead Women website where the woman had had a relationship with the perpetrator - as well as several extra cases such as those of male victims killed by their male partners.

The eight steps she discovered in almost all of the 372 killings she studied were:

A pre-relationship history of stalking or abuse by the perpetrator

of stalking or abuse by the perpetrator The romance developing quickly into a serious relationship

into a serious relationship The relationship becoming dominated by coercive control

A trigger to threaten the perpetrator's control - for example, the relationship ends or the perpetrator gets into financial difficulty

to threaten the perpetrator's control - for example, the relationship ends or the perpetrator gets into financial difficulty Escalation - an increase in the intensity or frequency of the partner's control tactics, such as by stalking or threatening suicide

- an increase in the intensity or frequency of the partner's control tactics, such as by stalking or threatening suicide The perpetrator has a change in thinking - choosing to move on, either through revenge or by homicide

- choosing to move on, either through revenge or by homicide Planning - the perpetrator might buy weapons or seek opportunities to get the victim alone

- the perpetrator might buy weapons or seek opportunities to get the victim alone Homicide - the perpetrator kills his or her partner, and possibly hurts others such as the victim's children

The only instance where a stage in the model was not followed was when men did not meet stage one - but this was normally because they had not had a relationship before, she said.

"We've been relying on the 'crime of passion, spontaneous red-mist' explanation [of killing] forever - and it's just not true," Dr Monckton Smith told the BBC.

"If you start looking at all these cases, there's planning, determination, there's always coercive control."

Image copyright Family photo Image caption Alice Ruggles was murdered by her ex-boyfriend in 2016

Alice Ruggles, 24, had been stalked by her ex-boyfriend, soldier Trimaan Dhillon, after their intense relationship ended.

Dhillon killed Miss Ruggles after breaking into her Gateshead flat in October 2016.

Her father, Clive Ruggles, said the outcome of the case "absolutely" could have been different if police had known about Dr Monckton Smith's eight-stage model.

"He had a history of stalking and controlling - the warning signs were there," Mr Ruggles said.

A domestic homicide review concluded Army officials had failed to record a previous domestic assault charge against Dhillon in Kent.

"That information wasn't known to police, Alice had no idea - we had no idea," Mr Ruggles said.

When Dhillon began stalking Miss Ruggles, she and her family "did not realise how much danger she was in", Mr Ruggles said.

"If [police] had looked at Jane's stages, they'd have realised - the constant messages, the emotional blackmail, all of that sort of thing - it was quite clear that he was already onto stage five," he added.

"We really believe that if this model gets out there and people start acting on it, then it will improve things for people and very likely save lives."

Image copyright Jane Monckton Smith Image caption Dr Monckton Smith said she believes her homicide timeline model can prevent killings

Dr Monckton Smith has taught her model to lawyers, psychologists, police forces across the country and probation officers.

She hopes that now the study has been published in the Violence Against Women Journal, the model can be rolled out more widely.

"As soon as they see it, victims and professionals are able to say, 'Oh my God, I've got a case at stage three', or 'My relationship is at stage five'," she said.

"Police have been incredibly receptive, and recognise the steps in cases they are working on, because it speaks to their experience and makes an order out of the chaos that is domestic abuse, coercive control and stalking," she added.

'Damaging headlines'

Dr Monckton Smith said once police learn the eight stages, they will be able to keep track of certain potential perpetrators - while victims will more easily be able to articulate to professionals what situation they are in.

She also said there should be more research into ways in which victims can leave controlling relationships safely, and into what causes people to seek control in intimate relationships.

The charity Women's Aid said improving understanding of domestic homicides could help save lives.

Head of communications Teresa Parker said: "We know that controlling and coercive behaviour underpins the vast majority of domestic homicides, and this important study shows why it is vital that we take non-physical abuse as seriously as physical abuse when considering a woman's safety.

She added: "A greater understanding will also reduce misleading and damaging headlines which cite jealousy, an affair or heartbreak as the reasons why women are killed by a current or former partner."

If you have been affected by any of the issues in this story, you can find information and support on the BBC Action Line website.