The NHS is facing a landmark test case that could pave the way for more than 800,000 equal pay claims, which will run parallel to recent high-profile claims against local authorities.

The precedent-setting case will attempt to prove that the implementation of the 2004 equal pay deal, Agenda for Change (AfC), was flawed, as the new salaries have not reflected skills and knowledge but were based instead on pre-AfC salaries, which were discriminatory.

Stefan Cross of Stefan Cross Solicitors, who is leading the test case, said: “This is a fundamental challenge to the basis upon which women’s salaries were being evaluated for Agenda for Change.”

The first case is set to start in October, when Eversheds associate Guy Bredenkamp will defend primary care trust Northumbria Care’s employment policy in Newcastle’s employment tribunal.

Bredenkamp will argue that the AfC principle was agreed to by unions, the Department of Health (DoH) and the NHS, and therefore should be accepted by all NHS staff.

Thompsons head of equal pay Caroline Underhill is advising the unions, which are co-defendants, and Deborah Haywood represented the DoH, advised by 11KBW’s Adrian Lynch QC.

Cross will argue on behalf of 1,200 claimants that the policy is based on discriminatory principles and will try to force the NHS to re-examine the AfC.

If successful it could form the basis for every NHS employee whose pay was affected by AfC to bring an equal pay claim.

Cross claimed discrimination between male and female salaries was rampant, with NHS employees receiving AfC salary rises based on previous discriminatory packages.

AfC was supposed to rid the NHS of discriminatory pay deals, but since its launch the number of equal pay claims has rocketed as female employees attempt to win back pay for all the years during which they were paid less than their male colleagues, who are now on the same pay scale as them under AfC.