Perhaps it was the bondage trousers his mother was so famous for creating in the 1970s but photographer Ben Westwood has made a career of depicting what some might see as the more explicit end of soft pornography.

Now he is moving onto the political frontline by spearheading a campaign against anti-pornography legislation that is due to come into force some time next year. He believes it will make possession of his own photography and other art illegal.

Westwood, 45, eldest son of fashion designer Vivienne and her first husband, Derek Westwood, has joined the campaign Caan - the Consenting Adults Action Network - which claims he is the first of several artists and celebrities planning to lend their names to the battle to overturn section 63 of the Criminal Justice and Immigration Act 2008, which gained royal assent earlier this year. It was intended to target people who view illegal hardcore pornography websites. Under the new rules, criminal responsibility shifts from the producer - who is already responsible under the 1959 Obscene Publications Act - to the consumer. It makes it illegal to have pornographic material that depicts necrophilia, bestiality or violence that looks life-threatening or likely to result in serious injury to the breasts or genitals.

Campaigners fear the new law will criminalise thousands of people who use violent pornographic images as part of consensual sexual relationships. 'They say this is about violence but it's distinctly about sex,' said Westwood. 'I feel the stick is always pointed at pornography as this terrible corrupting influence, this idea that it makes people do things that they wouldn't have done otherwise.

'My work has always been a campaign against that view. Now I find that someone is deciding to make owning my work a criminal offence. I don't think there should be laws, any laws, about sexuality. There are plenty of laws against physically damaging a person.'

Westwood's book of fetish-themed photography, F**K Fashion, published in 2005, contains images of women bound and gagged. 'The women are all beautiful consenting models,' said Westwood. 'Effectively, anyone who has a copy of my book could soon find they are breaking the law.'

The law means artists such as the Chapman brothers and Tracey Emin could find their work falling foul of the law. The Home Office insists the act is meant to target only internet porn.

The outlawing of 'extreme pornography' was itself the result of a three-year campaign by Liz Longhurst and MP Martin Salter who collected 50,000 signatures on a petition and won backing from police and the Home Office. Longhurst's 31-year-old daughter, Jane, was brutally murdered in 2003 by Graham Coutts, who had been viewing extreme pornographic sites depicting scenes of strangulation and faked murder and rape before he killed. He was jailed for at least 26 years.

Mrs Longhurst has said she is aware that many people see her as 'a horrible killjoy' but believes that if Coutts, who was referred to a psychiatrist as a teenager because of his murderous fantasies, had not had access to the porn sites her daughter would still be alive.

Salter said the ban was not a moral crusade but just plugging a legal loophole. 'This is not widening the law on anything that isn't already illegal, these sites are illegal but we can't block them because they take place in cyberspace, outwith the UK,' he said. 'People like Westwood need to understand we are not being prudish, we are not ratcheting up any bans on porn, just extending the law to cover people using it and trying to reduce the market for this stuff. No one is trying to stop consenting adults doing whatever they want in the bedroom.'

One of the sites used by Coutts is still available and another has simply changed its name after a campaign by the Mail of Sunday to close it down.