West Midlands Police have reported Channel 4 TV to the media regulator Ofcom over the way an Undercover Mosque programme in its Dispatches series was edited - claiming that it was misleading and could harm community relations.
They first asked the CPS to consider a prosecution of Channel 4 under the Public Order Act 1986 for showing material likely to stir up racial hatred, but were advised there was insufficient evidence for a criminal action.
The move came after police first investigated allegations against preachers featured in Dispatches, which tackled claims of Islamic extremism, in order to discover whether public order offences had been committed.
After viewing hours of footage, the investigators were sufficiently disturbed by the way the documentary had been assembled to seek a censure and possible legal action against its makers.
The Crown Prosecution Service also said the show "completely distorted" what the trio said, a claim that Channel 4 rejects.
Kevin Sutcliffe, commissioning editor for Dispatches, told Channel 4 News West that Midlands police had produced no evidence to support their claims. The police say they have the evidence, but do not wish to prejudice further possible developments by discussing it in public at this stage.
One of the men featured in the film making violently intolerant remarks against homosexuals told Channel 4 News that, in context, the remarks were clearly cited as examples of what breached free speech - and were not given his approval.
In fact, he said, he did not hold such views. His point was that they were, in his mind, parallel to "vile" comments made (in the name of free speech) about the Prophet Muhammed and Muslims.
Mr Sutcliffe did not respond directly to the point, but reiterated that he believed the techniques used by the programme makers were legitimate.
"We find it extraordinary that [the police]have gone public on these concerns without discussing them with us first," he added.
"To try and demonise the efforts of these people by taking their comments out of context was shocking", responded Abu Usamah, the Green Lane Mosque preacher featured.
But Mr Sutcliffe said the one-hour documentary, which was made over a nine-month period and broadcast in January 2007, allowed comment to be seen in a fuller context.
"All the speakers featured in the film were offered a right to reply and none denied making these comments, nor have any of them complained to Ofcom to our knowledge," he added.
The Metropolitan Police said on 7 August 2007 that a second Dispatches programme was also being investigated. 'Britain Under Attack' featured a man known as "Abu Mohammed" who disguised his face with a scarf and said British Muslims were in "a state of war" and that the 7 July bombings were "justified".
The programme (shown on 6 August) was also in the Dispatches series.
A Metropolitan Police spokesperson said: "We are assessing the content of a Dispatches programme broadcast on Monday 6 August to determine if any offences may have been disclosed."
Abu Usamah, featured in the second programme, said he was shocked when he saw himself depicted, saying his Green Lane mosque "has a 33-year-old tradition of preaching and teaching the moderate version of Islam."
Mr Usamah said he had been featured as saying homosexuals should be thrown from a mountain when in fact he was explaining it was an opinion featured in some books, which was not one he believed.
Crown Prosecution Service (CPS) lawyer Bethan David scrutinised 56 hours of media footage, only some of which was used in the broadcast.
She said: "The splicing together of extracts from longer speeches appears to have completely distorted what the speakers were saying."
The CPS has demonstrated it will not hesitate to prosecute those responsible for criminal incitement. But in this case we have been dealing with a heavily-edited television programme, apparently taking out of context aspects of speeches which in their totality could never provide a realistic prospect of any convictions."