A group of around 400 female workers at ASDA will take on their employer in a pay discrimination hearing which begins next week.

The Brierley v ASDA case revolves around the group of shop floor workers for the leading supermarket chain who are claiming they should be entitled to the same pay as the male workers in its distribution centres and warehouses on the basis that their jobs are of equal value although the latter are paid up to £4 per hour more.

The group of 400 employees roles range from shelf stacking roles to working on the checkouts. The workers are arguing that their roles are of equal value to the warehouse staff, their view being that the existing pay gap has been tainted by gender.

The claimants who work in shelf stacking roles are likely to say tasks of putting items from a shelf to a lorry are much the same as their role of unstacking items from a pallet and putting them on to the supermarket shelves.

ASDA has justified the pay difference on the basis that the warehouse employees work anti-social hours in uncomfortable conditions, a point that they will have to legitimately prove to win the case.

Should the case go against the retailer the repercussions could be huge – claimants will be entitled to six years (five years in Scotland) back pay to make up the current gap between shop floor and warehouse workers and will be entitled to equal pay going forward.

ASDA employs around 160,000 staff across the UK. The lawyer who represents the claimants in this case has so far had a reported additional 19,000 enquiries from colleagues.

While this specific case has been lodged by female employees, it is also understood that, if successful, male colleagues in shop floor roles may also pursue equal pay claims.

Stephanie Creed from the Employment department at Taylor Wessing LLP said:

“The Brierley v Asda case is believed to be the largest action of this kind in the private sector. If the claims are successful, or alternatively if they are unsuccessful but the judge suggests that a similar claim may succeed, other retailers who own their own distribution centres will be nervous; Sainsburys are already facing a similar claim.” “The case has wider implications for the retail sector. Companies who have shopfloor and warehouse staff with different gender groups and terms of pay are clearly vulnerable, but it is easy to see where employees could make arguments to extend this principle more widely – for retail businesses with separate online and bricks-and-mortar activities, for example.”

Equal pay legislation requires men and women to be paid the same for carrying out work of equal value, with the Equality Act 2010 giving some guidance on the matter, requiring employment tribunals to look at factors such as ‘effort, skill and decision-making’ in determining the value of a role.

While we have seen legal challenges on equal pay from the public sector, this case is one of the first mass claims within the private sector with potentially major implications for other businesses.

If successful, it is likely that other UK supermarket workers may consider making claims for gender pay discrepencies within their work places.