Murder victim told police she feared ex-partner would kill her

Katie Higton told police Marcus Osborne had hurt her and said he would "slit mine and the children's throats"

A police force was explicitly warned of a double murder by one victim days in advance, an official chronology obtained by the BBC shows.

Katie Higton and Steven Harnett were stabbed to death by Ms Higton's ex-partner Marcus Osborne at her home in Huddersfield on 15 May 2023.

Four days earlier, Ms Higton told West Yorkshire Police she feared Osborne would "seriously hurt or kill" her.

The force says "thorough reviews of the offences are being carried out".

The murder was reported at the very moment professionals were holding an urgent meeting to discuss the fears raised by Ms Higton, 27, and how to protect her and her four children.

Osborne, 34, has pleaded guilty to murder and other offences and is due to be sentenced at Leeds Crown Court.

The hearing comes a week after BBC Two's Newsnight reported that mothers of murder and manslaughter victims had accused West Yorkshire Police of failing to protect their children who had sought the force's help.

Newsnight's report said nine women in total had raised fears for their safety - and it can now be revealed that one of them was Ms Higton. Last week, in response to Newsnight, the force said it had since "implemented recommendations" and provided training to staff.

• Police force 'failed' women who were killed

Because of Osborne's guilty plea, there has been no criminal trial. The detail of events leading up to the murder of Ms Higton and Mr Harnett can only be reported because the BBC obtained the official chronology.

The BBC has been through several court hearings, including the High Court, to be able to report this information.

Prof Jane Monckton Smith, a criminologist and expert in domestic homicide, said when she first saw the chronology: "The hairs on my neck stood up."

Even with the limited information available, she said she could see that Osborne "ticked every box" as an imminent domestic homicide risk because he had a history of coercive controlling behaviour and domestic violence, and had made specific threats.

'Kill us both'

Friends described Ms Higton as "bubbly", "fun" and a "great mum" to her four children.

She had been in a relationship with Osborne for several years, but left him in late April 2023.

On 10 May 2023, Ms Higton made a report to police - but when she attended Huddersfield police station that day, no officers were available to see her, the prosecution told Osborne's sentencing hearing.

Ms Higton's street was cordoned off by officers after the bodies were found

On 11 May, she went to make a formal statement to West Yorkshire Police at the local station in Huddersfield. She told officers that on the previous day, she had spoken to Osborne and he had refused to accept they had broken up for good.

Ms Higton reported to the police that Osborne had hurt her and said he would "slit mine and the children's throats" if she told anyone "what he was like", according to the chronology. She felt he would "look for me and seriously hurt or kill me" if she did not go back to him.

Osborne had been jailed for violent offences against previous partners. Ms Higton herself had been the victim of abuse in a previous relationship.

She told police that Osborne had warned that if she got another boyfriend, "he will kill us both".

Marcus Osborne is due to be sentenced at Leeds Crown Court

Prof Monckton Smith has drawn up a "homicide timeline" based on her research into cases of domestic violence. She said Osborne was at "stage seven" of the timeline - the step before murder.

After reading about the case, she said: "I was horrified and deeply, deeply sad that all the signs were there."

The day after Ms Higton went to the police, on Friday 12 May, a social worker from Kirklees Council contacted her to offer "services" which she declined, the chronology shows. It is not stated what services these were - she might have been offered a place in a refuge, for instance.

Ms Higton agreed that she and the children would spend the weekend with relatives.

Police then arrested Osborne but released him shortly afterwards. He was served with a domestic violence protection notice, which meant he was not permitted to contact Ms Higton directly or indirectly or attend certain addresses and would be arrested if he breached these conditions.

Prof Monckton Smith said that in such circumstances, a domestic violence protection notice can escalate the risk instead of reducing it.

She believes police should have sought to detain Osborne, rather than arresting and releasing him. She also argues police need more powers to detain people who are "quite uniquely dangerous".

The following day, Sunday 14 May, Ms Higton went to the cinema with Mr Harnett, 25, whom she had recently met. She posted a photo of herself on social media. When she returned to her home at Harpe Inge - the main road in a 1950s council estate to the east of Huddersfield town centre - Osborne killed her.

He then used Ms Higton's phone to lure Mr Harnett to the house and killed him too.

Steven Harnett was attacked with a "bladed weapon" alongside Ms Higton, police say

It was a "planned" attack that lasted "several hours", said Judge Guy Kearl KC, who presided when Osborne pleaded guilty on 5 July 2023. According to police, Osborne had attacked Ms Higton and Mr Harnett with a "bladed weapon" and also assaulted another adult at the home.

The next morning, Monday 15 May, professionals from police, the local authority and other agencies gathered to discuss the domestic abuse and threats reported by Ms Higton three days previously. This was an "urgent" meeting, according to the official record.

It was interrupted by a phone call to a police officer reporting the murder. The officer told the meeting that "a live and very serious domestic violence incident was taking place at the home address".

Police and paramedics had been called and found the bodies at the Harpe Inge home. Osborne was arrested later that day.

West Yorkshire Police said the murders were "truly dreadful crimes"

Last summer West Yorkshire Police acknowledged it had had contact with the victims prior to the attack and, as required, the force had reported itself to the Independent Office for Police Conduct (IOPC).

The IOPC said at the time this was a case in which the local force should carry out its own investigation and the IOPC would review it.

West Yorkshire Police said the IPOC had requested further inquiries which are now being carried out by the force's Professional Standards Directorate and it cannot comment further at this stage.

In a statement, the IOPC said the murders had caused "considerable concern" and that its thoughts were with the families of Ms Higton and Mr Harnett. The statement added that the IOPC's work was "ongoing" and that it would provide a response "as soon as we are in a position to do so".

The force said the murders of Ms Higton and Mr Harnett were "truly dreadful crimes".

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