Four police officers were acquitted over a death in their custody after CCTV evidence confused experts when it also recorded a movie playing on their station's television.
Officers bringing Michael Powell into the custody suite at Thornhill Road police station, Birmingham, in the early hours of September 7, 2003 were recorded on a surveillance camera.
But Dogs of War, a 1981 thriller starring Christopher Walken and Tom Berenger, was playing on a TV on a shelf nearby.
Half-way through the trial, four of the ten accused - Pcs Lee Howard, Andrew Edwards and Luke Gill and Custody Sergeant David Williams - were cleared of misconduct by the jury on the directions of Deputy High Court Judge Sir Douglas Brown because the key CCTV evidence was unsafe.
The images revealed little but the camera's soundtrack - apparently capturing the comments of desperate police officers trying revive a man in their custody - seemed more compelling.
In court, jurors listened through earphones as the officers, according to the transcript, said "We're in the s**t", "gone unconscious" and "Michael, come on".
Courtenay Griffiths QC, prosecuting, told the court: "The Crown submit that the officers' conversations recorded on CCTV footage establish that they were aware of the severity of Mr Powell's condition at an early stage."
But under cross-examination of the experts who analysed the tape and produced the transcript, the evidence - vital in the prosecution of Howard, Edwards, Gill and Williams - was to unravel.
The CCTV had picked up two groups of people talking - the police officers based at Thornhill Road and actors in the big screen version of the Frederick Forsyth novel The Dogs of War.
Dismissing the case against the four, Mr Justice Brown said: "Generally, the presence of the Dogs of War made it difficult to interpret the soundtrack. Defence submissions are that the quality (of the CCTV evidence) is so poor that it would be dangerous to leave the material to the jury.
"The possibility of a mistake by a qualified expert was obvious and had been demonstrated. If he (Prof French) could make a mistake, how much easier could it be for a jury to do the same thing.
"It's one of the extraordinary features of this case that nobody in the early stages of this investigation had thought that it might be worth inquiring what the film was.
"It was left to the defence to buy a copy of the film."
The more Prof French listened to the CCTV sound-track, said the judge, the more different versions he said he was likely to come up with.
"That's no safe basis on which to put evidence before a jury," said Mr Justice Brown.
"The evidence must be regarded as suspect and unreliable," he added.