A school at the centre of a row for banning a 12-year-old Muslim girl from wearing a religious full-face veil was condemned as irrational by her lawyers in the High Court yesterday.

Mr Justice Silber was told that the high-performing school in Buckinghamshire had permitted, for nine years, all the girl’s elder sisters to wear the niqab. Despite just 120 of the 1,300 pupil-school being Muslim, the girls said that the school had been “very supportive of them as devout Muslims and the way they expressed their faith”, Dan Squires, counsel for the youngest sister, told the court. All girls had achieved high A-level results — one gaining four A-grades — and at least two had gone on to university, which demonstrated that it had not impaired their learning, he said.

As a result, Mr Squires argued, the ban on the youngest girl from wearing the niqab was not only against the principles of rationality, but thwarted a “legitimate expectation” that she would be allowed to wear it and breached her right to freedom of “thought, conscience and religion” under Article 9 of the European Convention on Human Rights.

The court heard that the 12-year-old, known only as Claimant X for legal reasons, had joined the grammar school in Buckinghamshire in September 2005. But after reaching puberty the following summer, she returned to school wearing the niqab. Three days into the new term, the headmistress contacted her parents. She was removed from the selective state school in October and moved to an alternative school where she could wear the veil.

The girl wants to return to her old school, wearing the veil, because she said she felt at home and entirely accepted.

In a statement she said that wearing the veil was a sign of her faith and that she felt it was compulsory to wear it. “I view the niqab as part of my identity,” she said. “Nobody’s forcing me to wear the niqab, it’s something I choose to wear and something I am proud of.”

Although uniform rules are clearly laid out for most pupils, the dress code for Muslim girls at the school is not written down.

In a statement, the headmistress, who took up her post in 2003, said that Muslim pupils understood that the scarf or hijab was acceptable, as long as it was in the uniform colours.

During the hearing Mr Justice Silber asked the barristers to address the issue of school security and whether the niqab hindered their need to see pupils’ faces.

Referring to the 1996 Dunblane massacre — in which Thomas Hamilton, shot dead 16 pupils and their teacher in Scotland — he said: “Everyone knows these days how security-conscious head teachers have to be at school. They have to be able to glance around and recognise who’s there.”

He also pointed that, for instance, barristers had to react to judges’ facial expressions, in the same way that teachers reacted to pupils’ facial expressions. He emphasised that, in raising the issues, he was not expressing an opinion one way or the other.

The Muslim Council of Britain has said that the policy of allowing the hijab headscarf is “quite sufficient to meet Islamic requirements” and the Muslim Educational Centre of Oxford has emphasised that not all Muslims agree with wearing the niqab. Buckinghamshire County Council said that it was up to individual schools to decide on their dress codes. The case continues.

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