Public sector unions have launched a challenge against the government’s decision to adopt the lower consumer prices index (CPI) inflation index, rather than the customary retail prices index (RPI) inflation index, for the purposes of statutory pension increases.

The government’s change has been imposed on public sector employees from 1 April 2011, and considerably reduces the value of their pensions according to unions.

Proceedings have been initiated for a judicial review by Unite, the Public and Commercial Services Union (PCS), the National Association of Schoolmasters/Union of Women Trustees (NASUWT), the Fire Brigades Union (FBU), and the Prison Officers Association (POA).

Gail Cartmail, assistant general secretary of Unite said: “The switch to CPI is, in our view, morally wrong and we hope to demonstrate through this action that it is also legally wrong.

“It is not acceptable for such a hugely significant change to have been forced through without any significant consultation.”

Chris Keates, general secretary of the NASUWT, added: “This unilateral and unnecessary change has been indiscriminately imposed on serving teachers and those who have already retired.

“For some teachers this could mean a loss of over £50,000 in the value of their pension over a twenty year period. This is simply daylight robbery of teachers and other public service workers who have dedicated their lives to serving the public.”

This marks the second consortium of unions to launch a legal challenge to the CPI switch in as many months. The Civil Service Pensioners’ Alliance (CSPA) joined forces with the Police Federation, the National Association of Retired Police Officers (NARPO), the First Division Association (FDA), the National Union of General and Municipal Workers (GMB) and Prospect to launch the judicial review on 18 April.

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