More than 60,000 Asda shop workers have begun a key stage in their fight for equal pay in a long-running case that could lead to more than £1.2bn in compensation. The employment tribunal started a hearing on Monday, expected to last about three months, into whether mainly female shop workers’ roles are of equal value to predominantly male warehouse workers who are currently paid up to £3.74 an hour more. This stage of the case, which stems from 2008 when some shop workers in Manchester sought to win equal pay to those working in the local warehouse, could be a key turning point. A ruling is expected early next year after a three-month hearing. The long-running court battle has implications for workers in all the major supermarkets who are involved in similar cases and is linked to an equal pay case at the fashion and homewares chain Next. The total industry bill for compensation in back pay could be as much as £8bn. Unequal pay has been a big battleground in the public sector, with female cleaners and dinner ladies taking legal action over claims they were paid less than men who worked as refuse collectors or street cleaners. The Asda case – which in reference to the Ford machinists strike of the 1960s has been dubbed “Made in Dagenham for the 21st Century” – was the first to be brought against a private employer. Nadine Houghton, a national officer for the GMB union, which is backing more than 20,000 members involved in the case, said: “Asda workers are making history. The result of this hearing will call time on the retailers undervaluing their predominantly women shop floor workers. “The entire retail sector has been built on the structural undervaluing of women’s work – but GMB members are changing this. “When the court finds shop floor work is of equal value to warehouse work it will be time for Asda’s majority owners – TDR Capital – to get round the table and begin settlement talks to resolve the sex discrimination in Asda’s pay structure.” An Asda spokesperson said: “We fully respect the right of current and former colleagues to bring this case; however, we strongly reject any claim that Asda’s pay rates are influenced by gender. There are numerous different jobs within retail and within warehouses. We continue to defend these claims because retail and distribution are two different industry sectors that have their own distinct skill sets and pay structures.” The argument over whether the roles are of equal value comes after a 2021 ruling by the supreme court, which backed a 2016 employment tribunal ruling, that Asda workers could compare their work with those in warehouse distribution centres. Michael Newman, a partner at the law firm Leigh Day, which is leading the Asda equal pay case and the other similar retail cases, said: “How Asda value the store jobs is made clear by the fact they are paid less than those in distribution centres. “This hearing is about whether the employment tribunal agree with that valuation – are things like customer service, and dealing with the public, as important as lifting cases of goods in the warehouses? Asda don’t have a business without their customers, and so the hearing will explore how Asda value those workers that deal with customers on their behalf.” If the workers prove their work is of equal value in this stage of the case, the next phase of the Asda case would look at whether there are alternative reasons why those working jobs of equal value might be paid differently. The Asda case could lead to more than £1.2bn in compensation, according to Leigh Day. The retail chain Next recently lost a tribunal on this issue and this might make it difficult for Asda and other retailers to successfully fight the shop workers’ action. Next is appealing against that ruling. Lauren Lougheed at Leigh Day said: “The equal pay team at Leigh Day is very encouraged by the huge success we experienced just last week on behalf of the many thousands of women we represent who have been fighting for equal pay at Next. “If we win at this stage 3 hearing, Asda will then have to prove that there is a genuine reason for the pay difference between store workers and warehouse workers which is not based on sex. “Next bosses failed to do this and our clients won. We are confident that the same will be true in the Asda claim.”