Thousands of solicitors and barristers could be entitled to claim extra fees after the government accepted it had unfairly discriminated against part-time fee-paid judges.

The Ministry of Justice has established a judicial pay claims unit (JPCU) to deal with claims for underpayment and compensation, but is not contacting those who may have a valid claim.

The development follows an unreported employment tribunal case, Miller v Ministry of Justice (January 2014). Judge Macmillan ruled that since April 2000, part-time fee-paid judges had been discriminated against by the ministry, which had paid them only a half-day fee for attendance at judicial training events.

The tribunal also found discrimination in the calculation used to determine the daily rate paid to some part-time judges, including recorders and deputy district judges, and in entitlement to London weighting, sickness and holiday pay.

Those affected have until 30 September to submit claims to the new unit. Details have so far emerged in a series of press releases posted on the government website (tinyurl.com/l2rb3qg).

The decision followed the Supreme Court’s February 2013 ruling in O’Brien v Ministry of Justice. This established that part-time judges are workers under the EU part-time working directive and are entitled to the same pension and conditions of service, pro rata, as their full-time colleagues.

Argument continues over the date from which extra pension claims can be backdated.

The ministry was not able to say how many judges are affected by the Miller ruling or how much has been budgeted for in additional payments.

An MoJ spokeswoman said: ‘We are announcing an amendment to training fees paid to some fee-paid judges in order to comply with recent judgments that followed the O’Brien case.

‘Some issues are subject to further proceedings, and we will continue to make legal representations to limit the potential overall cost to the taxpayer.’

John Platt, a retired circuit judge, told the Gazette: ‘I’m surprised that the ministry has decided not to take the initiative to contact those it has failed to remunerate properly before January 2014.

‘The opportunity now exists though the JPCU to claim both for historic underpayments and a lump sum on account of pension entitlement. It’s up to individuals to apply.’