Who can an employee compare herself with? 


The person the woman compares herself with is called the comparator and must be a man (or men) in the same employment. Normally, but not always, the comparator will be at the same physical workplace. It is helpful to choose a comparator whose circumstances are most similar to your own, to reduce the chances that the pay difference can be explained by factors other than sex. There is no need to identify the man by name at the outset.


It is up to an employee to choose her own comparator, and she can choose more than one, as long as they are engaged in “the same employment” (section 79, EA 10). 


There is no requirement for both to be employed over the same time period (section 64(2), EA 10), so there is nothing in law to stop a woman using a comparator who has left the organisation (although there may be practical problems relating to evidence gathering and so on). 


On the same basis, after a TUPE transfer, a transferring employee can continue to compare herself with a comparator whose employment did not transfer (Gutridge v Sodhexo [2009] IRLR 72).


However, in Walton Centre for Neurology and Neurosurgery NHS Trust v Bewley [2008] ICR 1047, the EAT decided that a woman cannot compare herself with a successor to her post, since the comparison process must involve a “concrete appraisal” of the work actually performed.


In Allonby v Accrington & Rossendale College [2004] ICR 1 328, the ECJ ruled that agency worker Debra Allonby was not allowed to compare her pay with that of a directly employed male colleague working alongside her, even though they both worked at the “same establishment”. They had different employers and there was no common controlling entity regulating their pay.


The fact that there are some men employed doing the same work as women for the same pay does not bar the women from bringing an equal value claim by comparing their jobs with those of other male workers who are paid more (Pickstone v Freemans [1988] IRLR 357). In Home Office v Bailey and others [2005] IRLR 369, the Court of Appeal held that female support officers could bring an equal pay claim using male governors as comparators, even though about 50% of support officers were male.


Where a woman has evidence of direct (but not indirect) sex discrimination in relation to her pay, but there is no actual comparator doing equal work (so that the sex equality clause cannot operate) she can claim direct sex discrimination, based on a hypothetical comparator (section 71, EA 10). The following example is taken from the EHRC Code of Practice: