It is well established that men and women should receive equal pay for equal work. There are three categories of equal work: 'like work', 'work rated as equivalent' and 'work of equal value'.
The retail staff are claiming that the work they perform is of equal value to Asda as the work performed by the distribution staff.
In order to succeed in their claims, the retail staff need to select appropriate comparators of the opposite sex who they say are carrying out work of equal value to their work. The comparators will then be used to assess whether there is any pay discrepancy.
An Employment Tribunal found that the retail staff could use the distribution staff for comparison purposes. Asda appealed, arguing that the distribution staff are not appropriate comparators as different parts of the business run its shops and its distribution centres, with different pay scales in place.
The Employment Appeal Tribunal has now rejected Asda's appeal. It has confirmed that the distribution staff can be used as comparators. The EAT based its decision on the fact that both the retail staff and the distribution staff are employed by Asda and their pay is controlled by Asda's executive board, overseen by parent company Wal-Mart.
Asda has already applied to the Court of Appeal for permission to appeal the EAT's decision and, given the value of the litigation, may well proceed to the Supreme Court if necessary. Even if the issue of comparators is settled in favour of the retail staff, an Employment Tribunal will have to determine whether the work performed by the retail staff and the distribution staff is truly of equal value to Asda's business and, if it is, whether any variation in pay can be justified on objective grounds.
Although the litigation is ongoing, valuable learning points can be taken from the Tribunal decisions to date: