The Law Society has launched a legal challenge against the government over criminal legal aid fees.

Chancery Lane has sent a letter before action to the Ministry of Justice over its decision to abolish the committal fee in either way cases in publicly funded criminal work.

The change, which came into effect on 3 October, means there will be no payment for work done in the magistrates’ court in either way offences where the defendant is committed to the Crown court for trial.

At the same time, the MoJ has introduced new fixed fees for either way cases in the Crown court and increased the fees paid for guilty pleas in magistrates’ courts.

In a consultation on the fee changes, the MoJ said too many cases that could be dealt with in the magistrates’ court are going to the Crown court, with increasing numbers ending with a guilty plea at a late stage, which it said is inefficient and does not represent best value in legal aid expenditure.

Lawyers have warned that this could prevent solicitors from acting for clients until matters reach the Crown court, which would leave defendants unrepresented, delay the process in the magistrates’ court and increase the number of cases going to the Crown court.

The Society’s letter giving notice of judicial review proceedings alleges that the decision is unlawful and irrational.

Chancery Lane said it had not taken the decision to bring legal proceedings lightly, but had been left with no option after attempts to resolve the matter with the MoJ failed.

Law Society chief executive Desmond Hudson said: ‘Throughout the consultation process, from the government’s legal aid reform green paper in November 2010, the consultation on the draft funding order and up to the lord chancellor’s decision to make the funding order, we have tried to explain why this change is a mistake for both the criminal justice system and the taxpayer.

‘Sadly the ministry has not been persuaded. We have therefore been left with no alternative but to pursue the litigation option which we tried hard to avoid.’

Malcolm Duxbury, president of the London Criminal Courts Solicitors Association, said: ‘If solicitors do act in these cases, the worst-case scenario would see them doing at least three appearances and a consultation unpaid.’

The former chair of the Law Society’s criminal law committee, Ian Kelcey, warned that without solicitors to make bail applications for those in custody, the prison population would rise.

He added: ‘If the MoJ is expecting firms to work for nothing, how long will it be before it expects them to pay for the work?’

An MoJ spokeswoman said it had received a letter from the Law Society in relation to committal fees, but could not comment further due to ‘impending live legal action’.

The Society has published guidance to solicitors on their professional obligations to clients in such cases, which can be found on the Law Society website.