Charities Age Concern and Help the Aged have been forced to take their campaign, to stop employers being legally able to enforce mandatory retirement, to the High Court after the European Court of Justice ruled the practice to be lawful in March this year.
But the case goes to the High Court the same week the Government announced it would be moving its review of the default retirement age from 2011 to 2010.
Michelle Mitchell, charity director, Help the Aged, said: "The Government should immediately put a stop to an arbitrary and unfair rule that stops people from working simply because of their age.
"Older workers make a huge contribution to the economy and will have the skills and experience needed to boost recovery as we come out of recession."
Nick Hobden, head of employment law and partner at law firm Thomson Snell and Passmore said: "If the Government cannot put forward sufficient evidence to satisfy the High Court that the 65 year old compulsory retirement regime was a proportionate means of achieving legitimate social policy aim and they lose the argument, this could leave some employers who have retired 65 year old plus employees, in accordance with law, having to argue that they had objective justification for doing so when they are required to respond to any claims that have so far been suspended but are allowed to proceed.
"Any amendment to existing legislation will not have retrospective effect as this would go beyond the powers of the European Communities Act 1972 which establishes the power to make regulations to implement an EU obligation, such as the age aspects of the European Equal Treatment Framework Directive, but not with retrospective effect. On that basis those employees who have brought claims for unfair dismissal and age discrimination against private sector employers, because they were retired at the age of 65 or over, ultimately may not succeed in their claims, as any potential change in the law, say in 2011, would not entitle them to be reinstated. Nor would they be likely to receive any compensation for any retrospective injustice.
"The position for public sector employers would be different, however. For public sector employers the Equal Treatment Directive does have direct effect depending on how it is interpreted by the High Court and the justification question. If the High Court found against the Government on the latter, there would be a retrospective effect. This would leave a two-tier approach: one law for public sector employees and one for private sector employees. How quickly would the Government intervene to put both on an equal footing?"