For years, there has been a secret conspiracy between prostitutes and the police.
Providing the public is not disturbed, increasing numbers of police forces are content to allow women to sell sex from saunas, massage parlours and private rooms.
This arrangement has even been formalised in some cities such as Edinburgh where the quasi-brothels have been given entertainment licences by the local authority and the police intervene only where there are complaints from the public.
But as a growing number of prostitutes choose off-street work, one of the country's most senior police officers believes it is time the Government and local authorities went all the way and legalised brothels.
The proposal, by Keith Hellawell, West Yorkshire's Chief Constable, is certain to outrage certain sections of society, and most politicians would probably still consider the measure as electoral suicide. However, there has been a fundamental change in attitude. Prostitutes are no longer simply cast as wicked sinners who corrupt. Issues of health and exploitation have come to the fore.
The extent to which the police no longer consider the use of saunas, massage parlours, and flats by prostitutes as a priority, or even much of a problem, was revealed in a recent survey of about 30 of the country's 40 vice squads. The work by the Centre of Criminology at Middlesex University, found an increasingly tolerant attitude. Officers often stated that their main priorities were to "clean up the streets - not to police sex". And they considered that off-street prostitution posed few law-and-order problems.
Half of the squads effectively ignored them and only intervened when the public complained. Areas in which this policy prevailed included: Bristol, Bradford, Cambridge, Coventry, Essex, Greater Manchester, Hampshire, Liverpool, Middlesbrough, Northampton, North Staffordshire, Stoke-on-Trent, Plymouth and Wolverhampton.
So far, only Edinburgh has offered a model of how a system of legalised brothels could work. By licensing saunas and massage parlours, the authorities in the city ensure high standards of health, safety and hygiene. Environmental health, fire and police officers approve the suitability of the premises. While this does not officially allow such businesses to operate as brothels, along with an unspoken police policy of tolerance, it has resulted in a regulated sex industry.
Edinburgh's licensing convener, Douglas Keir, is candid about the position: "We can't and don't license saunas for prostitution," he said. "What we have here are some saunas which appear to be selling sex, if they are not causing problems in a locality, and if there are no local complaints, then we are happy. If there are complaints, then we will investigate, but it's not a priority for us to look into unfounded allegations."
He went on: "The saunas seemed to have found a market over the years and it's obvious what the market is for, but the police take exactly the same line as us. It is not a priority for them. In fact, a while ago we had a group of senior police officers from Bradford who came to Edinburgh to study the situation."
Birmingham and Bristol are believed to be considering following their lead.
Prostitutes and organisations that represent them have long argued for changes in the law. There is concern that with the current drift towards unregulated off-street prostitution, women and girls are even more vulnerable to attack than on the street, where at least they can call for help.
In the near future, more police forces are likely to adopt the policy of turning a blind eye, especially with the public and politicians demanding greater action against more visible crimes, such as burglary, muggings, and assaults.
But the prospect of a radical change in the law remains dim as long as the issue is considered fundamentally a moral question.
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