Sometimes a single piece of hidden evidence can win a case. In 2003 Dr Harold Shipman was jailed for life for murdering 15 patients. Subsequently an enquiry, under Dame Janet Smith, positively ascribed 218 murders to him, though the number may well be higher. The sole irrefutable piece of evidence at his trial was a forensic examination of his patient records system. This evidence showed that, after having killed a patient, Shipman amended the patient’s record by backdating and inserting a false history of an illness which could be blamed for the death. But unbeknown to him the operating system of his computer kept multiple hidden logs of dates of amendment. A forensic examination of the computer gave the prosecution the evidence they needed for a conviction.

This autumn the world of forensic science and computing imaging is going to impinge upon the reality of the ordinary litigation solicitor. A new Practice Direction and a new E-Disclosure Questionnaire will mean that practitioners are going to have to either perform a detailed analysis of the digital evidence issues in every case or delegate the task to a specialist IT professional. Under the new Practice Direction not only will the parties have to sign a Statement of Truth in respect of the case but the E-Disclosure Questionnaire will have to be signed by a solicitor, client representative or IT consultant as being true and complete and the person signing the questionnaire shall be required to attend each Case Management Conference at which electronic disclosure issues are likely to be considered.

Recent changes have meant that disclosure has become a forensic discipline where all parties will need to consider Preservation, Format, Metadata, Proportionality and Privilege.

In all civil litigation it is the duty of the parties to preserve the evidence just as police “freeze the scene” in a criminal investigation. A decade ago preservation in commercial cases used only to mean looking at computer networks and checking that clients had back-up tapes with a regular back-up cycle. But today communicating can also be using Blackberries, E-mails, Instant Messaging and Texting. E-mails may be responded to automatically. Relevant transactions may be made without human intervention – such as downloading materials from a website after completion of a web form. Multiple versions of documents will be stored, as they go through their stages of development (think of the Iraq dossier produced by the Cabinet Office in the Iraq war which showed who had contributed to it and where the information came from).

Having preserved all the evidence does not mean that all the preserved evidence is disclosable. Much of it will be duplicated and irrelevant. All preservation means is that the material is available should, at some stage, a court require that it be produced to deal with an issue – such as a costs issue arising after a trial when one party is seeking payment for counsel’s fees for approving a draft witness statement.

The next issue to be determined is Format for disclosure. Should information be disclosed in static electronic formats (Adobe PDF files and TIFF files) or in a native format such as the format of an e-mail client like Microsoft Outlook. There are arguments both ways. Static formats exactly match the conventional lever-arch file and documents can be organized in folders. But in a very short time the volume of data overwhelms the disclosure process. Disclosure in a native format is more complicated since special software has to be used to access the disclosed documents. But it allows users to electronically search the disclosures and also provides some metadata (see below). It is a quick task to produced accurate chronologies and it may be the only way in which information can be intelligently handled. But the court and trial judge must also be prepared to accept and use the data in the native format – and this may require special software to be loaded onto the judge’s laptop. The compromise position has been to disclose in native formats and use this to produce digital bundles in static formats for the trial.

Metadata is data about data – hidden data which provides information which about other data. If a barrister says that he took three hours to review and revise a draft witness statement supplied in Microsoft Word a check of the metadata stored within the document can show precisely how long he actually took. In confidential information cases the examination of the metadata in a Blackberry handed in by a leaving employee may reveal that it has been backed up to a home personal computer, showing that the employee has kept a complete list of his employer’s confidential contacts and correspondence which he has not divulged at his leaving interview.

Proportionality is the requirement to make sufficient effort to provide disclosure only to the extent that is warranted by the value of the claim. Privilege allows the parties to filter out legal advice and correspondence – a major task in e-disclosure.

A litigation practitioner puts himself at risk in signing off an e-disclosure questionnaire if he does not understand all the above issues.