Criminal barristers who launched an ultimately unsuccessful legal challenge to the accreditation scheme for advocates have been landed with a £150,000 costs bill following the rejection of their application to appeal.

The High Court found today there was ‘no reasonable prospect’ of successfully challenging the judicial review judgment and there is ‘no other compelling reason’ for granting permission.

It slapped the appellants, whose legal team acted pro bono, with an order to pay £112,500 towards the costs incurred by the Legal Services Board and £37,500 towards the Bar Standards Board’s costs.

The High Court, led by Sir Brian Leveson, last month rejected all the challenges to the scheme advanced by the claimants - four individual barristers - but said concerns raised were ‘entirely genuine’.

The BSB announced amendments to the Quality Assurance Scheme for Advocates following the court’s recommendations. The claimants have until Friday to renew their application for permission to the Court of Appeal.

BSB director Vanessa Davies said: ‘We hope advocates will respect the court’s decision and understand that it is our duty to implement a quality assurance scheme. We hope we can now work together in implementing the scheme so that it best meets the needs of those we are all striving to serve – the client and the public.’

Chairman of the Criminal Bar Association Nigel Lithman QC said he would be talking to the lawyers acting for the criminal bar - a team at Baker & McKenzie led by Joanna Ludlum and counsel Dinah Rose QC at Blackstone Chambers - before deciding the next move.

Regulators welcomed the decision. Julie Brannan, director of education and training at the Solicitors Regulation Authority, said: 'We are pleased that the High Court has refused permission for the claimants to appeal to the Court of Appeal. The court has held that QASA is a proportionate and appropriate way to assure the quality of criminal advocacy. We are now moving ahead with the implementation of the scheme.'

The LSB said in a statement: ‘The arguments advanced by the claimants were simply not made out and that the LSB (along with the regulators) were entitled to conclude both that concerns about advocacy standards required regulatory action and that the scheme proposed was within its powers, not flawed by illegality or irregularity and was proportionate.’