Women's rights activists have accused the professional body representing lawyers in England and Wales of endorsing discrimination against women by refusing to withdraw its guidance on sharia wills.
The Law Society issued its guidance on ensuring that wills drawn up for Muslims comply with sharia in March, drawing criticism in the local press that it was effectively enshrining Islamic law in the British legal system for the first time.
In an open letter published on Thursday campaigners said the guidance, "a source of immense concern," encourages legal services "to accommodate highly gender discriminatory religious laws that are being increasingly defined by religious fundamentalists in our society".
The guidance informs lawyers that in general, under sharia, male heirs inherit twice the amount a female heir will receive and that illegitimate children are not heirs.
The letter said the Law Society's failure to withdraw the guidance amounted to a "a gross derogation of duty".
"Are we to assume that when the Law Society refers to equality, it does not include minority women's right to equality?" the letter said.
"Are we to assume that minority women are only to be recognised as different but not equal, and that equality and diversity are mutually exclusive? Are we to assume that the Law Society does not consider minority women as members of the public whose rights and interests the Law Society must also promote through the legal profession?"
According to media reports, the solicitors' watchdog deleted from its website references to professional guidance on drawing up sharia compliant wills in July.
Law Society officials were not immediately available for comment.
One of the campaigners who signed the letter said many women and girls from the Middle East, North Africa and Afghanistan - now living in Britain - had fled countries where sharia is practised. Sharia is based on the teachings of the Koran and the practices of the Prophet Mohammed.
"They too have experienced firsthand the discrimination of Sharia law. They have come to the UK in search of safety and to live in a country where women and men are treated as equals," said Diana Nammi, the executive director of the Iranian & Kurdish Women's Rights Organisation (IKWRO), at a protest outside the Law Society in April.
"Money is being put before women's rights. There is a lot of money to be made by lawyers from drafting Sharia compliant wills. We cannot allow for women's rights to be sacrificed so that lawyers can cash in," she told protesters.
The last census in 2011 showed that Muslims made up the second largest religious group in Britain with 2.7 million people - compared with the 33.2 million Christians that account for 59 percent of the population of 63.2 million.
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