A leading Jewish school has been accused of racial discrimination after it refused to accept a girl whose mother was a convert to the religion.

Her parents are taking legal action against the JFS (formerly the Jewish Free School) for rejecting their daughter’s application, The Times has learnt.

The girl’s father is an Orthodox Jew and her mother, who is the school’s head of English, converted to Judaism more than 20 years ago. But the Office of the Chief Rabbi does not recognise the conversion and so refuses to accept that the child is Jewish.

The couple claim that the school’s admissions code breaches race laws, because it favours children with Jewish-born mothers. Jewish custom dictates that the faith line passes through the mother.

Children from two other families who consider themselves Jewish have also been refused a place. The school insists that the preference it shows to pupils whose mothers were born Jewish is a religious rather than a racial issue.

JFS is one of Britain’s oldest Jewish schools and is the largest Orthodox Jewish school in Europe, with 2,000 pupils. It is described by Ofsted as outstanding and is oversubscribed every academic year.

Philip Hunter, the Chief Schools Adjudicator, recently ordered JFS to scrap admissions criteria designed to be used if the school ever came to be undersubscribed. He ruled that these parts of the code, which give priority to children with a Jewish father or grandparent over those with no Jewish roots, were breaking race discrimination laws.

But the adjudicator did not instruct JFS to alter the main part of its code. This means that it can still favour nonpractising children whose mothers were born Jewish over those whose mothers converted to the faith and are religiously observant.

Mr Hunter ruled that the school was not breaking race relation laws by favouring children born to Jewish mothers, saying this was Jewish law and was therefore a religious issue.

David and Kate Lightman want to force the school, near Harrow, north-west London, to change its admissions policy and admit their daughter, who is 13. The couple complained to the adjudicator and were backed by their local council, the London Borough of Brent. Another couple objected on behalf of their child and are also taking legal action.

Mr and Mrs Lightman are seeking a judicial review in the High Court to resolve their four-year battle. The couple observe Orthodox practices and want their daughter to join her friends at the school.

Mr Lightman, a former pupil at the school, said that his wife had taught there for 17 years and converted to Judaism in Israel in the 1980s, under the country’s Chief Rabbi.

But he said that Britain’s Office of the Chief Rabbi, which acts as the school’s religious authority, questioned the validity of his wife’s conversion and so had ruled that his daughter was not Jewish.

“As far as they’re concerned, she’s not Jewish,” he said. “When I was at the school in the 70s it had a much more open ethos, but now seems to have a much narrower interpretation.”

Mr Lightman, who runs a design company, said that the couple intended to take legal action, but added: “We’re a family of average means against a large, well-financed establishment. It’s been incredibly difficult for my wife teaching at the school, although she’s had a lot of support from the staff and parents.

“My daughter leads an active Jewish life and asks why she can’t go to the school. I find it hard to explain to her, other than saying there are small-minded people stopping it from happening. We will seek a judicial review on the grounds that we believe it [the admissions code] is racially discriminatory against people not born into the religion.”

Russell Kett, chairman of the JFS governors, said that the Office of the Chief Rabbi helped the school to determine whether applicants were Jewish. “The issue [of admissions criteria] has been considered by the schools adjudicator, he has given his ruling and we have complied with the ruling.”

A spokesman for the Office of the Chief Rabbi, said: “Matters of a personal status are confidential. The family concerned has not waived confidentiality so it is impossible for us to give more detail or comment.”

Most Orthodox Jewish schools use similar admissions criteria. Immanuel College in Hertfordshire says all children “require authorisation from the Chief Rabbi.” Hasmonean High School, in North London, said it adopted the same code.

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