The European Court of Human Rights will give judgment today on cases involving four Christians who say they were discriminated against in the workplace.
Sixty-year-old British Airways employee Nadia Eweida, from London, says she was prevented from wearing a visible cross necklace.
It is hoped that success today will lead to an overhaul of the Equality Act and other diversity legislation.
Judgment will take place at 0900 UK time.
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