Gracie Spinks was unlawfully killed by the man she had reported for stalking, an inquest jury has unanimously concluded.

Ms Spinks, 23, was fatally stabbed by 35-year-old Michael Sellers as she tended to her horse at Blue Lodge Farm in Duckmanton, Derbyshire, on June 18 2021. Sellers was later found dead a short distance away.

The 10 members of the jury – who wore pink and purple wristbands in Ms Spinks’ memory – concluded that she was unlawfully killed by Sellers, whom she had reported to police over stalking concerns several months earlier.

Multiple failings already admitted by Derbyshire Police were referred to in the record of inquest filled in by the jurors, but they had been prevented by a coroner from deciding whether the failings had contributed to Ms Spinks’ death.

Following the inquest, Ms Spinks’ family said Derbyshire Police had let her and them down, while the force said that it fully accepted the findings of the jury and had made “significant” changes.

Returning their conclusion on Thursday, in which Sellers was referred to as “the supervisor”, the jury foreman said: “Derbyshire Constabulary had admitted the following serious failings.

“However, it could not be concluded that these failings contributed to Gracie’s death on June 18 2021.

“It was the supervisor that killed Gracie.”

The jury returned its conclusion after retiring on Wednesday, having previously been instructed by coroner Matthew Kewley that it could only return a conclusion of unlawful killing.

The coroner said there could be “no alternative” explanation due to the nature of the evidence, which he said pointed “overwhelmingly” to the fact that Sellers killed Ms Spinks and then took his own life.

Ms Spinks met Sellers at work in 2020 but, after meeting socially on a handful of occasions, she declined to pursue a relationship with him, the inquest heard.

But Sellers became “obsessed” with her and would repeatedly contact her, ask colleagues to report on her activity, and would “spy” on her on CCTV.

He was sacked when Ms Spinks reported him to their employer after he was seen waiting in a lay-by near Blue Lodge Farm in January 2021, after eight women previously reported his inappropriate conduct towards them.

Ms Spinks also contacted Derbyshire Police, but Sellers was only rated as low-risk and given words of advice in a car park, with no further action taken despite him telling officers he thought the pair were in a relationship.

A rucksack – later found to belong to Sellers – was discovered on a bridle path near Blue Lodge Farm in May 2021, which contained knives, a hammer, an axe, Viagra tablets and a note saying “Don’t lie”, but this was dismissed by police and no further action taken.

The police had accepted multiple failings prior to the jury’s conclusion concerning their investigation into Ms Spinks’ complaint and their handling of the bag.

The jury agreed in their conclusion that there were failings, including that Sellers should not have only been given a warning following Ms Spinks’ complaint and police should have done more to trace the owner of the rucksack.

Several officers gave evidence in the inquest, with one saying the weapons should have been a “concern” and another telling Ms Spinks’ family he was “truly sorry” and that the force “should have done better”.

Mr Kewley said that a Prevention of Future Death Report would be issued to Derbyshire Police’s Chief Constable and others over the coming days.

Thanking the jury, he said: “I really just want to give you my thanks for the way that you’ve engaged over the last few weeks.

“You’ve shown a great deal of effort and commitment.”

He also extended his condolences to Ms Spinks’ family, several of whom had attended since the start of the hearing on October 30, describing their resilience as “remarkable” throughout.

Speaking following the inquest, Ms Spinks’ father Richard Spinks, said: “Gracie was our daughter, the light of our lives. She was the gel that kept us all together.

“We miss her every day and will continue to remember her every second, of every minute, of every hour, as long as we live.

“Derbyshire Police let Gracie down, they let the family down, they let themselves down, and we hope that they do not let anybody else down.

“They do need to change how they operate from top to bottom.”

Reading a statement on behalf of Derbyshire Police, Detective Superintendent Darren De’ath said: “Put simply, as a force we failed Gracie, and for that, I can only offer my own and the force’s most sincere apologies.

“We have now heard the conclusion of the jury – who we thank for their time and dedication in hearing the evidence and considering it so closely – and we accept these fully.

“We await any further recommendations that may come from the coroner and will review these in due course.

“But I want to be clear that, since Gracie’s death in June 2021, significant work has already been completed to tackle the failures that were identified prior to the inquest.

“There has also, over the last two-and-a-half-years, been significant changes to the ways in which we as a force receive and investigate stalking reports – as well as how we support and safeguard victims of these crimes.

“However, none of this seeks to minimise the failings that we have seen in this case and the force fully accepts the failures that were part of this most tragic set of circumstances.”