'My brother told police Creswell was a killer, but they ignored him'

David Lusby says he often takes a moment to ask himself: "What would my brother Paul do?"

He was a "good guy… a charismatic gentleman", David says. Adding that he "looked up" to him a lot and he trusted his sense of judgement.

But David also admits there are times he gets frustrated with Paul, who took his own life in July 2022.

And he's also angry, because he believes police ignored Paul's concerns about his friend Katie Simpson and the man who killed her, Jonathan Creswell.

Katie, who was 21, died six days after being admitted to Altnagelvin Hospital in Londonderry in 2020.

Creswell, her sister's partner, called 999 pretending he found her and the showjumper's death was initially treated as suicide.

Paul was also part of the equestrian world and had known both Katie and Creswell for some time.

Paul first contacted police on the day following Katie's hospital admission.

David says that Paul "knew that Creswell was a killer", and he knew "nothing was being done".

He "spent 700 days living with the terror knowing that Creswell was free. Paul knew a killer was on the streets," his brother told BBC Radio Foyle's North West Today programme.

"He notified police she was in domestic servitude and he had some sort of conviction against him."

It would not be Paul's last attempt to alert police.

A recent review into Katie's death revealed that in the initial stages of the investigation, vital information was provided to police by members of the public, but it was not acted upon.

This includes the call made by Paul to Crimestoppers in August 2020 - the day after she was admitted to hospital.

The report further found that a police interview with Paul was not properly recorded and when he later asked about it, he was told the notes had been destroyed.

Paul also took his concerns to the police ombudsman's office.

The review's author Dr Jan Melia, concluded that the notes should not have been discarded and that all material from the investigation should have been retained.

Katie was just 10 years old when Creswell began grooming her.

He described in the Melia review, as "a predator who used sexual abuse and rape as a tactic targeting young women including Katie".

In 2009 he was sentenced to six months in jail for a catalogue of abuse against a former girlfriend.

On the second day of his trial for Katie's murder in 2024, Creswell was found dead at his home.

By that time David and the wider Lusby family had been mourning the loss of Paul for just over two years.

He says Paul was a "good man, a noble man" who was "trying to do the right thing".

"And they ignored him and I want to know why. I want to say the system failed him but to fail at something means you tried. They didn't try."

He says the family believe Paul had been living in fear in the time leading up to his death.

"He felt afraid, he had received threats. Paul was all over the country trying to get Creswell, going places where he was going. Paul was a complete menace to Creswell."

"I have many questions - why did you do it? Why aren't you here? If anything, this is when we need you."

He says the family have lost "such a good man" and that police "just tried to silence him by ignoring him".

The Melia report references "serious collateral harm" caused to Paul, linked to the police delay in investigating Katie's death.

One of its conclusions states: "Paul Lusby felt intimidated by Jonathan Creswell after cooperating with police. The prolonged delay in the investigation is understood by his family, to have significantly exacerbated his distress, ultimately contributing to his death."

On Monday, The Irish News reported that the Lusby family is to launch legal action against the Police Service of Northern Ireland (PSNI).

David says the family believes there should a public inquiry.

"There needs to be a proper investigation, there needs to be a public inquiry, an investigation into all the police officers involved."

It remains a difficult and traumatic time for Paul's family.

"It's affected my parents, obviously, really bad. The loss of a son and a brother, they didn't deserve this," David says.

In a statement, the PSNI said it acknowledged the suffering and pain of the Lusby family.

It also highlighted apologies in recent weeks from both Assistant Chief Constable Davy Beck and the Chief Constable Jon Boutcher for the failings of the PSNI into the initial investigation into the death of Katie Simpson.

The statement said the PSNI acknowledged failings which includes not listening to those who raised early concerns.

Hugh Hume, the Chief Executive of the Police Ombudsman's Office, said he will be contacting the Lusby family "to offer a meeting to discuss the matters raised, and I hope this will allow me to address their concerns".

"When Paul first contacted us, we assessed whether his complaint was one that was within our remit to investigate. Among the criteria which had to be considered was whether he was personally involved in the incident, or was acting on behalf of someone who was," he said.

"While our initial assessment was that the complaint was not within our remit to investigate, we offered advice on how the matter might be progressed. Paul subsequently provided additional information, which allowed us to investigate a new complaint.

"We are grateful that he brought these issues to our attention, and his complaint was one of a number which prompted a detailed investigation of the police handling of Katie's death."

If you have been affected by any of the issues raised in this story, information and support can be found at the BBC's Action Line.