A London school's ban of the cornrows hairstyle resulted in "unlawful, indirect racial discrimination", the High Court has ruled.
Mr Justice Collins said the ban by St Gregory's Catholic Science College in Harrow was not unlawful in itself, but should have taken into account individual pupils' family traditions.
A 13-year-old boy, "G", was refused a place because of the hairstyle.
The school said it was "naturally disappointed" and may try to appeal.
"St Gregory's is proud of its rich cultural and ethnic diversity and is run on the belief that everyone at the school is equal and made in the image of God," it said in a statement.
G's African-Caribbean family claimed the style was of importance to his cultural identity.
He was refused entry to St Gregory's as an 11-year-old on his first day in 2009 because he had the cornrows style – with hair braided, close along the scalp.
He was forced to attend another school. He does not wish to return to St Gregory's despite the outcome of the case.
In a statement read out to the High Court at an earlier hearing, G said: "When I saw my idol, David Beckham, cornrow his hair, it showed me that he appreciated African hair styling, and that we are all the same underneath it all."
Mr Justice Collins, sitting in London, ruled that the hair policy was not unlawful in itself, "but if it is applied without any possibility of exception" such as in the case of G, "then it is unlawful".
The judge said in future the school authorities must consider allowing other boys to wear cornrows if it was "a genuine family tradition based on cultural and social reasons".
Following the hearing, G's solicitor, Angela Jackman said: "This is an important decision.
"It makes clear that non-religious cultural and family practices associated with a particular race fall within the protection of equalities legislation."
The school said it had "always striven to ensure that our uniform policy, including that related to hair styles, is fair and equitable to the wide range of cultures which make up our school community".
The court had not decided G was treated unlawfully or that the school had been guilty of any kind of discrimination, it added.
School's cornrows ban 'critical'
School cornrows ban 'is unlawful'
HM Courts Service
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