Commander Steve Allen of the Metropolitan Police said that a decision by ministers last month to drop proposed legislation had been greeted by some ethnic minorities as a signal that forced marriage was acceptable.

His concern about the about-turn, which was partly prompted by fears that the new law would stigmatise Muslims, is shared by a Crown Prosecution Service director and the head of Scotland Yard’s Homicide Prevention Unit. The head of a South Asian women’s charity said yesterday that girls were already suffering the consequences of the decision.

Between 2003 and 2005, 518 forced marriages were recorded in London, and in 2005 more than 140 in Bradford. Campaigners say those are merely the tip of the iceberg.

Most cases in Britain involve Muslim families, although the practice is not restricted to any particular religious or ethnic group. Most victims are aged between 16 and 20 and many suffer physical assault, death threats and false imprisonment, usually at the hands of close family members.

Suicide rates among young Asian women are more than three times the national average and about 12 women every year die as a result of so-called “honour killings”.

Last September the Home Office launched a consultation paper on creating a specific criminal offence of forcing someone into wedlock. Although the proposal was welcomed by many victims’ groups, some organisations complained that it would increase racial segregation. The Muslim Council of Britain gave a warning that such a law might become “another way to stigmatise our communities”.

When Baroness Scotland, the Home Office Minister, announced the Government’s reversal, she said that most of those consulted “felt that the disadvantages of creating new legislation would outweigh the advantages”.

Mr Allen, who tackles honour-related violence and advises the Association of Chief Police Officers on the issue, told The Times: “There is a school of thought which suggests that a specific piece of legislation may have the impact of driving the practice further underground . . . For me the persuasive argument is about the message we send out. We have already received feedback from community groups suggesting that the decision not to make it a criminal offence means it must be all right.

“We need political and faith leaders from within these communities to stand up and utterly reject these practices.”

Nazir Afzal, the Crown Prosecution Service director for London West, said that a new law would have helped campaigners in minority communities to stamp out forced marriage. “I have heard it said that a new criminal offence would be just another stick to beat the Muslim community with, but my belief is that we should be carrying our own stick,” he said.

“More than 60 per cent of cases involve Muslim families, particularly Pakistani Muslim families, yet there is no faith foundation for it A forced marriage in Islam is no marriage at all. The community has a responsibility. I hear dialogue from victims but I don’t hear a great deal from Muslim men.”

Mr Afzal was closely involved in the case of Samaira Nazir, 25, who was murdered because her family disapproved of the man she wanted to marry. Her brother and cousin were jailed for life earlier this month for the killing.

Laura Richards, the Homicide Prevention Unit head, said that banning forced marriage “would have sent out a very powerful message that it is not to be tolerated or accepted”.

Jasvinder Sanghera, of the Nirvana Asian Women’s Project, which helps victims, said: “A new criminal offence would have given the victims the power to say to their family, ‘You can’t do this to me. It’s against the law.’ It’s a chance missed and it’s already doing damage. Political correctness is not an excuse for moral blindness.”

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