The Employment Appeal Tribunal has begun hearing the government's challenge to a ruling that its transitional pension arrangements for 210 judges amount to unlawful age discrimination.

Six High Court judges, including Sir Rabinder Singh, who now sits in the Court of Appeal, were among 210 claimants who challenged the lord chancellor and the Ministry of Justice over transitional provisions regarding pension reforms.

In January the employment tribunal ruled that the lord chancellor and Ministry of Justice had treated and continued to treat the claimants 'less favourably than their comparators because of their age'. Tribunal judge Stuart Williams said the lord chancellor and MoJ had 'failed to show their treatment of the claimants to be a proportionate means of achieving a legitimate aim'.

Sir Alan Wilkie, who retired from the High Court bench on 31 January, is hearing this week's appeal, which has been joined to a case involving 5,000 firefighters over their transitional pension protections.

Barrister John Cavanagh QC, of 11 KBW in London, is representing the lord chancellor and ministry. Cavanagh acknowledged that the judges and firefighters are 'worse off' under the government's new pension scheme. He told the tribunal that judges also faced a 'doubly whammy' as a result of tax changes.

However, the litigation concerns only  the transitional provisions, which were introduced 'because of a sense of moral responsibility to those closest to retirement', Cavanagh said. The Hutton Report, which in 2011 recommended wholesale public sector pension reforms, 'had not recommended any transitional provisions at all'.

Pension protections given to older judges and firefighters 'did not come at a financial cost for those who were further away from their retirment', Cavanagh said.

Decisions about the final transitional provisions were made 'at the highest level of government', he added. However, 'it was never suggested by representatives of the Fire Brigades Union and the lord chief justice and other senior [judicial] representatives at any time before the new scheme or transitional provisions were finalised that we should have transitional provisions that treated younger judges better than colleagues closer to the normal pension age... To protect younger people in preference to older people would feel wrong. It would feel unfair'.

Discussing policy aims and means, Cavanagh said the employment tribunal judge's 'overriding error...was not allocating a margin of appreciation to the UK and Welsh governments'.

Counsel for the judges are expected to make their submissions tomorrow.

Solicitor Shah Qureshi, of London firm Bindmans, representing the High Court judges, told the Gazette: 'It is clear these reforms discriminate against younger judges and disproportionately impact on women and ethnic minorities. So the key question is whether protecting those closes to retirement at the expense of younger judges, women and ethnic minorities is legitimate and proportionate.

'The employment tribunal did not believe the changes were justified. The onus is on the government to justify the changes and explain why it believes the tribunal's judgment was flawed.' 

The hearing continues.