The new Attorney General's Guidelines on Disclosure of Information in Criminal Proceedings are an attempt, says the document, to strike "a fair balance between the respective needs of the participants in the investigation and trial process". The Criminal Procedure and Investigations Act 1996 introduced a new scheme for the disclosure of information by the prosecution, although serious concerns have been expressed about its operation throughout its three-year existence. The new guidelines come after a lengthy public consultation exercise and are to be welcomed.

The guidelines will give greater consistency of disclosure throughout the country. If followed, they should inevitably mean that much more material held by the prosecution, and which might be of assistance to the defence case, will now be made available. The practice which has grown out of "counsel-to-counsel" disclosure should also cease: "It is inconsistent with the requirement of transparency in the prosecution process."

The prosecution is expressly told that it should disclose any information that might assist the defence with a bail application. This will undoubtedly occur before any consideration has been given to primary disclosure. Similarly, the prosecutor must consider disclosing in the interests of justice any material relevant to the sentence, for example information which might mitigate the seriousness of the offence or assist the accused to lay blame in whole or in part upon a coaccused or another person.

Often the prosecution will provide the defence with all the evidence upon which the Crown proposes to rely in a summary trial in the Magistrates Court. The guidelines expressly say that the prosecutor should provide all this evidence, allowing the accused or their legal advisers sufficient time to consider properly the evidence before it is called. This leads to two interesting points: the first is that defence solicitors should expressly ask the prosecution if they have disclosed all the evidence upon which they rely in advance of the trial; second, if a statement is produced from a witness at court on the morning of the trial, they may be able to apply for an adjournment with a possible wasted costs order against the prosecution, saying that they have not complied with the disclosure guidelines.

Since the operation of the act, there has always been concern: first about primary disclosure of evidence that might undermine the prosecution's case; and then secondary disclosure once the defence case statement has been served and which might assist the defendant. If the new guidelines are followed there should be a greater and more uniformed disclosure of information and material. This will inevitably depend on the subjective view of the disclosure officer, but the guidelines urge greater discussion with the prosecution lawyers, and if in doubt material should be disclosed.

It is easy to see that any information that may assist in the cross-examination of a prosecution witness or undermine a victim's complaints should be disclosed. Not so clear is material that might give rise to an argument that the defendant's rights under the European Convention of Human Rights have been affected or there are grounds for an abuse of process application. The guidelines do say that any evidence relating to the defendant's mental or physical health, intellectual capacity or treatment in custody should be disclosed. Presumably, defence lawyers should look for any statements from friends, acquaintances or former employers of the accused given by way of background information and which are not material to the allegation.

The Director of Public Prosecutions accepted that the act was not being applied universally or consistently, as Parliament intended. The guidelines are an attempt to improve the operation of the legislation. They are detailed and far-reaching. They cover both the existing position and extend areas sensibly. If properly applied, they should substantially allay the concerns that have been expressed about the legislation and are therefore most welcome.

Michael Caplan is a partner at the criminal litigation department for Kingsley Napley and vice-chairman of the Solicitors Association of Higher Court Advocates.