A decision by the Manchester Employment Tribunal at a preliminary hearing, in what is the largest ever private-sector equal pay case, has opened the floodgates for a wave of claims against Asda.

Under UK legislation, female employees are entitled to enjoy contractual terms that are as favourable as those of a male comparator, if they are employed in jobs of equal work. The key issue in the Asda case is whether the supermarket's in-store staff roles, which are mainly held by female workers, are of equal value to higher-paid jobs in its male-dominated distribution centres.

At the preliminary hearing, the Tribunal had to determine whether the Asda store workers could compare themselves to the distribution workers for the purposes of an equal pay claim.

Under section 79 of the Equality Act 2010, an equal pay comparison is only valid between the claimant and a chosen comparator if they are both employed by the same employer and work at the same establishment; or if they are both employed by the same employer and work at different establishments but 'common terms apply at the establishments'.

Asda sought to argue that the sets of employees were not comparable as they were based in different locations with different pay arrangements, and that the pay differentials reflected market rates. However, the Tribunal was not convinced by this argument and held that the statutory test was met and, as such, that the distribution workers are a suitable comparator.

This ruling will now mean that the test case can proceed and will clear the way for over 7,000 claims currently in waiting to follow. The claimants in these cases are seeking rectification and compensation for historic discrimination, and it is estimated that the total value of the claims could exceed £100million.

Whilst this is just a decision in respect of a preliminary matter, and we will be keeping a careful eye on the test case as it unfolds, the decision is likely to impact on other employers in the retail space, as the disparity between shop floor staff and warehouse staff is not unusual.

In light of this preliminary ruling, employers may wish to reassess how they carry out job-evaluation across the whole of their business; and ensure that equal pay considerations are kept in mind cross-establishment.

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