Charlene Downes has been missing since 2003. Police have been criticised for a catalogue of failures which led to the collapse of her murder retrial
An independent review found that police surveillance techniques were 'handled poorly and unprofessionally' and as a result nobody is now likely to be convicted of killing Charlene Downes, 14, who was last seen in 2003.
Her mother today said she felt 'badly let down' after the Independent Police Complaints Commission (IPCC) recommended that seven officers should be disciplined over the matter.
Charlene was last seen on November 1, 2003 when she kissed her mother goodbye and went to see friends on Blackpool Promenade.
Two men appeared at Preston Crown Court in 2007 in connection with her alleged murder but the jury was discharged after it failed to reach verdicts.
The prosecution claimed the murder suspect was overheard talking about having sex with the teenager and that she had 'gone into kebabs'.
A retrial was scheduled to begin a year later but the Crown Prosecution eventually dropped the case because it had 'grave doubts' about the reliability of some of the evidence.
Iyad Albattikhi, 31, was formally cleared of Charlene's murder and Mohammed Raveshi, 51, was acquitted of helping to dispose of her body.
Charlene's mother, Karen Downes, of Blackpool, said she was 'devastated' at the findings of the police watchdog.
'We feel badly let down by the police and the Crown Prosecution Service,' she said.
Grieving: Charleen's parents Karen and Robert Downes feel 'badly let down' by the deficiencies of the police investigation into their daughter's disappearance
'I was devastated when I saw the report. It's very upsetting.'
Lancashire Police apologised to the Downes family but said it remained a live investigation and its officers were still committed to solving the case.
The investigating team were guilty of a strategic and tactical failure in the management of the audio and video material they obtained, the IPCC concluded.
Proper records were not kept, material was not fully transcribed and the overall integrity of the material was not ensured.
The use of untrained and inexperienced officers in the inquiry was also criticised as was the way a human intelligence source was handled.
The IPCC recommended that one officer should face a disciplinary hearing, one should receive a written warning and five others should receive words of advice.
Two other officers who retired prior to the investigation cannot be considered for disciplinary sanctions. It has been recommended that the current role of another officer who retired during the investigation, but was then re-employed in a civilian capacity, be considered.
Assistant Chief Constable for Lancashire Police, Andy Cooke, said he acknowledged the findings.
He said: 'It is clear that certain aspects of the case have not been well managed - specifically during the time prior to the trial - and for this we must certainly apologise to the Downes family.
'I want to reassure them and our local communities that we have learned the lessons from this and have moved on quickly in terms of the handling of such information.'
Naseem Malik, IPCC Commissioner for the North West, said: 'What is abundantly clear is that the covert surveillance aspect of Lancashire Constabulary's investigation into Charlene's disappearance was handled poorly and unprofessionally.
'The IPCC's managed investigation has identified a catalogue of errors which undermined the court case.'
Funny Boyz takeaway: Owner Iyad Albattikhi was cleared of Charlene's murder because the Crown Prosecution had 'grave doubts' about the reliability of some of the evidence
'The failings in Lancashire Constabulary's investigation can only have compounded that distress. Lessons must be learned from this matter to ensure such failures cannot happen again.'
The inquiry was one of Lancashire's longest-running investigations involving a child missing from home before detectives switched the focus to a murder hunt.
More than 3,000 people were spoken to by police and almost 2,500 statements were taken.
No trace of Charlene has ever been found.
The prosecution in the 2007 trial alleged that Jordanian immigrant Mr Albattikhi, who owned Funny Boyz fast food shop in Blackpool, strangled the teenager after having sex with her.
The court heard Charlene was one of a number of young white girls who gravitated to the resort's fast food shops to have sex with older men.
Expelled from school, she spent her time hanging around the shops on the promenade.
Prosecutors claimed either Mr Albattikhi, known as Eddie, or his Iranian landlord and business partner, Mr Raveshi, was having underage sex with her and they would be in trouble if the police found out.
Both men denied even knowing her.
Police started a murder inquiry when David Cassidy, a former friend of Mr Albattikhi, said the accused's brother had told him the schoolgirl had been strangled and chopped up.
Detectives later bugged both Mr Raveshi's home and car with secret listening devices and claimed the defendants could be heard on the tapes discussing her murder, with references to eating her body and a burial place.
Det Sgt Jan Beasant spent two years and around 2,500 hours listening to the contents of the tapes but such was the poor sound quality that much of the content was hard to decipher at the trial with sound experts and police disagreeing over what was actually said.
John Bromley-Davenport QC, defending Mr Raveshi, claimed Det Sgt Beasant was totally unqualified for the task of listening to the tapes and already knew a huge amount about the case.
Ian Goldrein QC, representing Mr Albattikhi, accused Mr Cassidy of telling a pack of lies and that his evidence was unreliable because he had a lengthy criminal record for dishonesty.
The jury of seven men and five women deliberated for 49 hours before they conceded they could not reach a verdict on either defendant.