Criminal defence lawyers have launched a campaign to ensure all police forces provide qualified interpreters to non-English speaking detainees at police stations.

A 2007 national agreement on the use of interpreters – drawn up by the Office for Criminal Justice Reform in consultation with the Association of Chief Police Officers and legal professional bodies – requires the police to provide interpreters to detainees who need them.

Northumbria Police, however, is one of several forces to insist the defence provides its own interpreter to avoid contamination of evidence when the same individual translates for both prosecution and the defence. It is up to the defence to foot the bill. Superintendent Vince Stubbs of Northumbria Police’s criminal justice department said the practice complies with the agreement, which says that, if the defence requires a second interpreter, it is responsible for the cost.

Michael Robinson of north-east firm Emmersons said the highest standards of translation are crucial when an individual’s liberty was at stake. ‘And yet solicitors are being asked to find an interpreter themselves, often in the middle of the night. They have to bear the cost themselves and then attempt to recoup the money from the Legal Services Commission – which might decide it’s not their responsibility and refuse to pay up.’

Malcolm Fowler of Birmingham firm Jonas Roy Bloom said most police forces subscribe to the National Register of Public Service Interpreters, which vets interpreters for security, criminal record and professional competence. ‘Sadly, most firms of solicitors can’t afford it and so, unlike the police, can’t know who is best qualified for the job. Mistakes can be made, leading to miscarriages of justice.’

Cetty Zambrano, communications director at the NRPSI, said the institute had opened talks with the Law Society to see whether a ‘corporate’ arrangement could be agreed to benefit solicitors and interpreters alike. ‘The alternative for solicitors is investing time and effort to find locals with foreign language skills and sponsor their training, which is rarely practical.’

The commission said its policy is for the police to appoint an interpreter for the prosecution, but that in many force areas police and defence could share an interpreter where appropriate. ‘This can reduce costs and also reduce the time clients spend in custody, bringing efficiency savings for both the police and the defence.’

Robinson called on the Law Society to issue a guidance note reminding solicitors that the police have obligations under the national agreement on the use of interpreters. A Society spokeswoman said it would investigate the problem. ‘In the light of that we will discuss what further action needs to be taken.’