BARBARA Mills QC, the Director of Public Prosecutions, has moved to reassure critics of the new criminal disclosure rules that they will not lead to miscarriages of justice.

Mills last week told a conference organised by the British Academy of Forensic Sciences that the CPS and the police were working together to comply with the Home Office code of practice to ensure new disclosure rules are properly enforced.

She added that prosecutors and police would, in a unique exercise, undergo joint training sessions in the New Year on the new laws.

“I am confident that with the help of this comprehensive training package, there will be fair and effective justice for everyone involved in a trial,” she said.

The new procedures required by the Criminal Procedures and Investigations Act 1996 mean defence lawyers can no longer routinely search through all the evidence gathered by the police.

Under the rules, it will be initially down to the prosecutors, with the help of police, to disclose any material they believe may undermine their case.

In the secondary disclosure stage, which will apply in the crown court, the defence is required to give a statement of their case, and the police will look again at unused material and advise the prosecution whether any of this material will be useful to the defence. If not, there will be a signed certificate stating there is no such material.

But despite Mills' assurances, the new law, which comes in to force on 1 January, was attacked at the seminar by Christopher Murray, head of criminal law at Kingsley Napley and vice-president of the London Criminal Court's Solicitors Association.

He said the act was the product of political jockeying to win votes rather than a well-implemented reform of the criminal justice system.

“Legislation of enormous significance is being passed with little or no debate, such is the paranoia of either party that they might be seen as soft on crime,” said Napley.

“This Act strikes at the heart of our criminal justice system and threatens to reverse the burden of proof. It seems it will be left to a police officer to decide whether material held by the police should be disclosed by them as relevant to the defence.”

David Phillips, the Chief Constable of Kent and secretary of the Association of Chief Police Officers' Crime Committee, also addressed the seminar. He said: “If we trust the police to record evidence it is redundant to imagine that they will criminally conspire to conceal what they should disclose”.