The family of murdered schoolgirl Nikki Allan have been promised a full independent review into the police investigation into her death.

In May, David Boyd, 55, from Stockton, was found guilty of beating the seven-year-old with a brick and stabbing her in a disused building in Sunderland in 1992.

The Northern Echo: Nikki Allan Nikki Allan (Image: Contributor)Read more: The horrific murder of an innocent that shocked and sickened the country 

His conviction came after the re-opening of Northumbria Police’s investigation in 2017 when advances in DNA testing revealed the link to a former neighbour.

The force initially prosecuted another of Nikki's neighbours, George Heron, but he was cleared of murder in 1993.

Northumbria Police has previously apologised for failures.

The Northern Echo: George Heron was wrongly charged with Nikki's murder but was clearedGeorge Heron was wrongly charged with Nikki's murder but was cleared (Image: North News)

The Northern Echo: Nikki's neighbour David Boyd was the actual killerNikki's neighbour David Boyd was the actual killer (Image: Contributor)

The Northern Echo: Boyd remained at large for over 30 years until his conviction in May this yearBoyd remained at large for over 30 years until his conviction in May this year (Image: Contributor)

Read more: George Heron who was wrongly accused speaks out

Northumbrian Police and Crime Commissioner Kim McGuinness has previously said she can 'only imagine' the impact the wait for justice has had on Nikki’s family and yesterday she met in person with Nikki’s mother, Sharon Henderson, to discuss her experience.

Ms Henderson, who has campaign for justice since 1992, said she was taking legal action against the force and called for a public inquiry after Boyd was convicted and jailed for life with minimum term of 29 years.

She said: "Since the trial I don't feel any different. The anger is still there because there are so many things still unanswered.

It was a positive meeting and she believes Nikki's case should be looked at again, how it was investigated and what went wrong.

"They need to look back into to see if there was anything missing because I believe there was more involved in Nikki's murder.

 "She agreed that too many things went wrong. I have come away a bit clearer in my mind that Nikki's case is going to get looked at again."  

The Northern Echo: Kim McGuinness, left, with Sharon Henderson Kim McGuinness, left, with Sharon Henderson (Image: Contributor)

In her role as Police and Crime Commissioner Ms McGuinness is required to act as the public’s voice in policing in Northumbria and put in place the appropriate scrutiny to ensure the force is being effectively held to account.

During yesterday’s meeting with the family, she confirmed her plans to commission an independent organisation to conduct a review of formal complaints made by the family.

Get the latest news, sports, and entertainment delivered straight to your device with a subscription to The Northern Echo. Click here 

Ms McGuinness said: "More than 30 years ago, Sharon Henderson and her family suffered an incredible loss when Nikki Allan was murdered. Their long wait for justice has only compounded their pain.

“Northumbria Police has always remained committed to finding the person responsible, and officers showed that dedication when they used new forensic techniques to finally secure a conviction for Nikki Allan’s murder.

"Hard-working officers brought justice to this case. However, questions remain for Sharon and her family, including over the initial investigation. I agree that Sharon deserves answers. 

"Once the formal complaint is received from the family, I will invite an independent organisation in to review the complaint.

“A process such as this will take time, but Sharon and her family will finally get the answers they need.”

Read next:

A spokesperson for Northumbria Police said: “We have acknowledged that mistakes were made in the original investigation and regret the length of time it has taken to get justice for Nikki and her family.

“However, we never gave up in the hunt to find the person responsible for Nikki’s murder and due to the exemplary work of officers and forensic advancements we were able to secure a conviction.

“Sharon and the family also deserve credit for their determination and campaigning to see Nikki’s killer brought to justice.

“The impact the 30-year wait for justice has had on them is unimaginable.

“Should we receive a complaint in relation to the case, we would liaise with the Independent Office For Police Conduct to ensure an appropriately thorough and independent assessment.”