Whitehall mandarins have joined rank-and-file civil servants, specialist staff and police organisations to launch a judicial review of the Treasury's decision to change the index used to up-rate public pensions.

If successful, the legal challenge could force the Government to re-think its plans for all public pensions, including those within local government and the NHS. Chancellor, George Osborne, has announced his intention to up-rate public sector pensions in line with the consumer price index (CPI) inflation rate. Currently, pensions across the sector are up-rated in line with the higher rate retail price index which, unlike the CPI, takes account of increases in housing costs.