The family of Harry Dunn, who died in a collision with US spy Anne Sacoolas, have submitted a formal complaint over the conduct of a former chief constable.
The 19-year-old motor-biker died after he was hit in a head-on collision by Sacoolas in 2019, who was exiting the American intelligence base RAF Croughton in Northamptonshire.
On Wednesday, an independent report found that officers prioritised the welfare of Sacoolas, who was able to leave the country claiming diplomatic immunity, after officers did not arrest her.
Harry's mum, Charlotte Charles, who received an MBE for services to road safety, said the family had been let down "really, really badly."
The family have now written to the office of the Northamptonshire Police, Fire and Crime Commissioner, Danielle Stone, to ask whether the contents of the report will be referred to the police watchdog, the IOPC.
The report criticised former chief constable Nick Adderley for multiple failures, including giving inaccurate public statements about Sacoolas's immunity, claiming she could waive it when in fact only the US government could do so.
Mr Adderley, who was sacked last year after lying about his military record, was found to have caused a breakdown in relations with Mr Dunn's family due to his "erroneous" public statements.
In the email, seen by Sky News, Radd Seiger, spokesperson for Harry's family, wrote: "Although Mr Adderley has already been dismissed for gross misconduct in relation to unrelated matters, this report provides damning evidence of multiple leadership failures and misconduct directly attributable to him in the handling of this case.
"These failures have caused lasting harm to the Dunn family, undermined public trust, and compromised the integrity of the investigation.
"Justice was ultimately done despite him, not because of him, and due to the skill and perseverance of the investigation team and the CPS. The story is scarcely believable".
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Following a long fight for justice by Mr Dunn's family, Sacoolas eventually pleaded guilty to causing death by careless driving via video link at the Old Bailey in December 2022.
She later received an eight-month prison sentence, suspended for 12 months.
The family is now calling on the government to conduct an inquiry into the case.
Northamptonshire Police, Fire and Crime Commissioner Danielle Stone said: "I have asked my team to assess this complaint using the statutory guidance for complaints against Chief Constables so that any next steps can be decided."
Sky News has also contacted Mr Adderley for comment.
(c) Sky News 2025: Harry Dunn's family file complaint against former police chief after report
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