A police review panel will meet "within weeks" to discuss how the Billie-Jo Jenkins case should be taken forward, the BBC has learned.
Billie-Jo Jenkins' killer is still at large after Mr Jenkins' acquittal
Billie-Jo's murder remains unresolved after her foster father Sion Jenkins was formally acquitted on Thursday.
Sussex Assistant Chief Constable Geoff Williams will lead the panel, with forensic experts and the Crown Prosecution Service, it is understood.
Mr Jenkins, 48, from Lymington, Hants, has criticised the police inquiry.
He said there had been a "single-minded and desperate determination to convict me at all costs".
It is understood the panel will look at where the murder investigation currently stands, as well as shaping any further review.
ACC Williams urged people to come forward with information
The BBC has also learnt there is no active incident room assigned to the murder case, and there will only be one if recommended by the review panel.
Representatives from Sussex Police Authority, as well as the senior investigating officer, Det Ch Insp Graham Pratt, will take part.
After the jury at Mr Jenkins' second retrial failed to reach a verdict, ACC Williams said: "If any person has any information which can shed new light on the death of Billie-Jo, I urge them even at this stage to talk to the police."
Sion Jenkins was convicted in 1998 of Billie-Jo's murder in Hastings in 1997, but he was freed on appeal in 2004 and a retrial was ordered.
Jurors at his second retrial could not reach a verdict on Thursday and the prosecution said it would not be proceeding with another one.