A new law to ban extreme pornography, which was brought about by a campaign by the mother of a murdered Brighton schoolteacher, has been criticised. Critics, including members of Britain's bondage, domination and sadomasochism community, say the new law will criminalise thousands of people who would be unfairly targeted.

Section 63 of the Criminal Justice and Immigration Act 2008 comes into force on January 26.

It makes possession of pornographic images depicting scenes of extreme sexual violence an offence punishable by up to three years in prison.

Liz Longhurst's 31-year-old daughter, Jane, was killed in 2003 by Graham Coutts, who admitted to a fixation of viewing images of women being strangled and raped.

After his conviction in 2004, Mrs Longhurst vowed to bring about a change in the law banning such images. Her campaign brought support from 50,000 people and The Argus.

Opponents to the law have said they have no problem with the clauses banning people from viewing images of bestiality and necrophilia but say its vague wording could mean that images of consenting adults taking part in violent role play would be outlawed. Claire Lewis, a 35-year-old disabled rights activist, has set up the Consenting Adult Action Network (Caan) to campaign against the law.

She told a national newspaper: "I firmly agree that images of non-consensual activities which involve violence should be criminalised but this is a badly worded law that risks criminalising thousands of ordinary people.

"The Government seems to be convinced that if people like us look at pictures for too long we ll end up turning into abusers.

"That's outrageous."

Another group, called Backlash, has hired human rights law firm Bindmans to fight any cases if they come to court."