Shamoon v Chief Constable of the Royal Ulster Constabulary [2003] UKHL 11 is a UK labour law case concerning the appropriate test for determining who is a comparator.

She was dismissed and made a claim under the Sex Discrimination (Northern Ireland) Order 1976, which is the same as the SDA 1975, and now found in the Equality Act 2010.

It said that the appropriate comparators were two male chief inspectors who were in the same branch and had the same duties, in which they continued, but who had not had complaints against them.

The Northern Ireland Court of Appeal held that her claim failed because the two comparators she pointed to who had done similar appraisals had had no complaints made against them.

He noted that choosing which characteristics are relevant for the purposes of comparison should not defeat the purpose of the legislation, ‘which is to eliminate discrimination against women on the ground of their sex in all areas with which it deals.’ Lord Nicholls said that tribunals, may sometimes be able to avoid arid and confusing disputes about the identification of the appropriate comparator by concentrating primarily on why the claimant was treated as she was.