The family of Katie Simpson have said they felt there had been "a lack of accountability at more senior level within policing" following a report into the death of the 21-year-old showjumper.
The report found that a police investigation into the murder of Ms Simpson was "flawed" and failed her family.
Ms Simpson died in hospital six days after an incident at a house at Lettershandoney, Co Derry, in August 2020.
The Police Ombudsman for Northern Ireland (PONI) delivered its verdict on the PSNI investigation into the murder of Ms Simpson this morning.
It found detectives had treated her death as a suicide for months, despite repeated warnings about her killer Jonathan Creswell.
Ms Simpson's family said they felt the disciplinary action had been concentrated on the lower ranking officers and ought to have been directed at more senior investigators.
A statement from the family’s solicitors, KRW Law, said that the family intend to raise the issue in a meeting with PSNI Chief Constable Jon Boutcher and PONI Chief Executive Hugh Hume.
The family said that they had been left with the "gnawing sense" that there had been "blame passing" going on.
Katie's father Jason said their daughter had been "stolen" from them.
Her mother Noleen said the family had been failed and but for the actions of a senior officer and some family members who pursued the issue, Jonathan Creswell would still be controlling, hurting and murdering women.
Nothing should take away from his "psychopathic evil", they said.
A statement from KRW Law also said that the report’s findings "are a stepping stone on what’s still a long tortuous road to justice for the Simpson family".
"The passage of time over the last few years since Katie’s death has not healed the deep wounds felt by the family. They have demonstrated commendable bravery in the face of unimaginable distress and anxiety," it said.
The family thanked PONI for "exposing a lot of what they suspected all along".
They also thanked PSNI officers "who railed against a hitherto immoveable fixed policing stance which eventually resulted in the long overdue decision to charge Cresswell with murder".
Ms Simpson’s family said they appreciated Chief Constable Boutcher’s "fulsome personal apology" earlier this year, but now wanted to hear from him about the concerns they raised.
Her family added that the report’s findings will assist the work of the coroner in Katie’s inquest and will also inform civil legal actions arising from the identified failings.
They also urged the three recommendations made by PONI in the report to be immediately implemented.
"The family really hope that never again will any other family have to endure what they’ve been put through over the last three years. If at least that happens then it will give the family some modest comfort to know that Katie’s sad passing will have left a lasting legacy."
