A private investigator that reviewed Nikki Allan's murder case said Northumbria Police "failed" the family.
Sharon Henderson, Nikki's mother, has long criticised the force's handling of her daughter's murder.
On 7 October 1992, Nikki was lured to the Old Exchange building at night, battered with a brick and stabbed repeatedly, before being dragged and dumped, dead or dying, in the basement.
The family lived near Boyd in flats in the East End of the city called The Garths, which have since been demolished, close to where her body was found.
31 years later, David Boyd has been found guilty of ending Nikki's life.
Speaking to ITV Tyne Tees, Sharon claimed the police investigation was a "ripple effect" with officers looking further afield than the Garths, but she said "I was asking for three doors down".
Until now, no one had been convicted in connection with Nikki's death 31 years ago, making it one of Northumbria Police's most high-profile unsolved cases.
Jen Jarvie, a private investigator who worked with Sharon in recent years and currently lectures in professional policing, said: "The police have a difficult job and particularly with a child murder. However, in this particular case, they failed Sharon, they failed Nikki, monumentally to begin with, but continued to do that for a lot of years."
Referencing Boyd living as a free man for decades, Jen said: "They had an ideal suspect there, but they failed to pinpoint him time and time again."
A brief background on the investigation:
Northumbria Police led the investigation of missing and murdered seven-year-old girl Nikki Allan in 1992. Officers arrested neighbour George Heron and after three days of questioning, under duress, he admitted to killing Nikki, having denied it 120 times before.
Boyd, aged 25 at the time, was never considered as a suspect and gave a witness statement after Mr Heron was been charged, explaining his movements on the night of the murder. After Mr Heron was cleared of Nikki’s murder during his trial at Leeds Crown Court in October 1993, he went into hiding. Police said they were not looking for anyone else in connection with the murder.
Boyd was arrested in April 2017, and rearrested in April 2018. He was charged with murder in May 2022.
David Boyd, 55, of Chesterton Court in Norton, Stockton-on-Tees, now faces a life sentence following his conviction of murdering Nikki in October 1992. The jury at Newcastle Crown Court have been hearing evidence for three weeks and took approximately one-hour-and-a-half to come to a unanimous verdict.
Dani Garavelli was a crime reporter working for the Newcastle Journal at the time of Nikki's murder.
Dani reported on the case at the time and stayed in touch with the story over the years. She said Nikki's tragic death has stayed with her and will, forever.
The transcripts from George Heron's interviews were dissected by members of the media, including Dani. She recalls it was "particularly shocking" that it in 1993, it seemed Heron was led by police to give an account of what happened to Nikki, to "match what they needed to hear".
"In other words, [police were] dropping clues and basically manipulating him to describe it in a way that they knew. There were quite clearly things he didn't know, and they led him to it."
Dani believes Boyd would never have been in the dock, if it was not for Nikki's mother Sharon.
Northumbria Police did not take any questions outside of court, but Assistant Chief Constable Brad Howe issued the following statement:
“Today is about justice – for Nikki and her family. We thank them for their patience and strength over the last 30 years and our thoughts very much continue to be with them.
“David Boyd hid his crime, lying about his involvement and prolonging the family’s suffering, knowing all along that he had taken the life of their little girl.
“The investigation into Nikki’s murder has been one of the most complex and comprehensive ever conducted by Northumbria Police. I’m extremely proud of the investigative team and all those who played their part in securing this conviction.
"I further hope this sends a strong message that no matter how long ago an offence took place, we will do everything we can to see justice served.”
Boyd will be sentenced on 23 May 2023.
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