MPs have accused West Midlands Police of seeking to undermine freedom of speech by making a “perverse” complaint about a Channel 4 programme that exposed extremism in a British mosque.

Police claimed that the Dispatches programme Undercover Mosque misrepresented the views of Muslim preachers and clerics through misleading editing. The programme featured undercover recordings from speakers alleged to be homophobic, antiSemitic, sexist and condemnatory of nonMuslims.

West Midlands Police rejected calls to take action against the preachers for stirring up racial hatred. Instead, they pursued a complaint against the film-makers, accusing them of undermining community relations.

But Ofcom, the media watchdog, threw out the police complaints. It found that the programme had “accurately represented the material it had gathered and dealt with the subject matter responsibly and in context”.

The programme showed one preacher saying: “By the age of 10, it becomes an obligation on us to force her [young girls] to wear hijab, and if she doesn’t wear hijab, we hit her.”

Other statements included: “Take that homosexual and throw him off the mountain”, and: “Whoever changes his religion from Al Islam to anything else – kill him in the Islamic state”.

Abu Usamah, a preacher at the Green Lane mosque in Birmingham, was secretly filmed saying: “If I were to call homosexuals perverted, dirty, filthy, dogs who should be murdered, that is my freedom of speech isn’t it?”

Ofcom said: “Undercover Mosque was a legitimate investigation, uncovering matters of important public interest. Ofcom found no evidence that the broadcaster had misled the audience or that the programme was likely to encourage or incite criminal activity.”

David Davis, the Shadow Home Secretary, said: “Once they [the police] were clear that no criminal offence had been committed, it was, in my view, a serious misjudgment to continue to pursue the editorial team and risked impeding freedom of speech.

“The Dispatches programme raised matters of wide public interest, touching on security and community relations. The documentary handled inherently sensitive issues in a responsible manner. Having been advised by the Crown Prosecution Service that no criminal charges should be brought, there was no cause for a police complaint to Ofcom. That decision drew the police into scrutinising editorial decisions of a television producer, which is not an appropriate law enforcement function and risks deterring legitimate investigative journalism.”

Kevin Sutcliffe, Channel 4’s deputy head of news and current affairs, who oversees Dispatches, said: “This was a rigorous investigation conducted over nine months and involving great difficulty in its filming, substantial personal risk for the reporter and a great deal of considered judgment in the edit suite.

“All the preachers featured were offered a right to reply and none of these individuals complained to Ofcom about the way they were represented. In these circumstances it seems perverse that Channel 4 should have found itself the subject of a police investigation.”

West Midlands Police said that the programme caused concern for a number of people who made complaints to the force. A spokesman said: “The CPS did raise significant concerns around the production of the programme.”

He added: “It is usual practice . . . to make referrals to regulatory bodies. We acknowledge the findings from Ofcom, which also received and investigated complaints made directly from independent members of the public.”

Ofcom rejected all 364 complaints received from viewers, saying that they appeared to be part of a campaign. A complaint from the Kingdom of Saudi Arabia that the programme treated it unfairly was also rejected.

Don Foster, media spokesman for the Liberal Democrats, said: “This whole case raises serious questions about West Midlands Police and the CPS in what appears to be an attempt to censor television, stifle investigative journalism and inhibit open debate.”

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