The march of information technology continues and lawyers need to keep abreast of its reach and implications. The recent publicity attracted by the rise of machine-learning artificial intelligence, as well as the scandal of the Post Office’s prosecution of numerous postmasters and postmistresses, makes the issue especially topical.
What do we mean by electronic evidence? The definition provided for “electronic evidence” given by the Council of Europe Guidelines on Electronic Evidence In Civil And Administrative Proceedings, adopted by the Committee of Ministers of the Council of Europe on 30 January 2019, is as good as any: “any evidence derived from data contained in or produced by any device, the functioning of which depends on a software program or data stored on or transmitted over a computer system or network.”
Proceedings in England and Wales feature the presumption that mechanical instruments operate correctly absent contrary evidence. This arises from a Law Commission recommendation found in its 1997 paper Evidence in Criminal Proceedings: Hearsay and Related Topics. This led to the repeal of s 69 of the Police and Criminal Evidence Act 1984 which previously required express evidence that a computer was being operated properly and was working properly at the time of its relevant use.
The sheer complexity of computers makes them rather different from the mechanical devices at which the presumption was originally aimed. Inter-connecting elements include the physical hardware, software, the relationships between interconnected networks and the role of human operators in software development and inputting data. It is difficult to see that the presumption of efficacy can extend very far into the components of these systems: it is all very well to presume that electronic circuitry usually performs its myriad tasks efficiently, but software requires frequent correction of constantly identified bugs via the endless updates that interrupt the activities of modern users. And the frailty of human data input is epitomised by the famous acronym GIGO: garbage in, garbage out. Indeed modern software development contracts tend to exclude any warranty for interruptions due to software error, dealing with the issue via ongoing maintenance and support services rather than denying the possibility at source.
In order to displace the presumption, it will be necessary to seek disclosure of the metadata that surrounds the collation of electronic evidence. Metadata is the data that provides information about other data, explaining its provenance by way of its origin, nature and lineage. Error logs and update histories may be useful, and evidence may be presented to show that the system has been professionally managed with reliable error reporting to the system owners. Any historic retention of data will have required a series of steps ranging from its original storage and onwards archiving, possibly including migration into more modern forms of software and transfer between networks. Any of these lines of enquiry may reveal potential witnesses who might be summonsed to give evidence at court as part of a sustained challenge to a system’s reliability and integrity. Bold and bare assertions that any particular system is robust should be resisted absent a detailed account of its workings.
Indeed the “Known Error Log” played a significant role in the Post Office litigation. The experts agreed that it was a useful source of information about Horizon bugs, albeit it was likely to be a limited window onto reality rather than a complete picture. The Post Office had sought to argue that its disclosure was not relevant, reasonable or proportionate, which the judge found to be a contention lacking a rational basis.
The Post Office litigation culminated for our purposes in the decision of Fraser J in Bates v The Post Office Ltd (No 6: Horizon Issues) [2019] EWHC 3408 (QB). The Judge accepted that various iterations of the Horizon software were unreliable, leading to unexplained shortfalls and discrepancies in their branch accounts. The Post Office’s riposte was that its systems were robust and thus unlikely to be responsible for the asserted problems. Only a concerted effort in group litigation managed to achieve the scale of disclosure that ultimately contributed towards identifying the injustices that had taken place. The financial risk was generally prohibitive to individual litigants.
Another major piece of litigation involving electronic evidence arose from the evidence of fraud relating to English language tests at a number of colleges running the Test of English for International Communication (TOIEC). The issue first achieved notoriety following a BBC Panorama programme about the malpractice, in which many attendees were complicit. Many thousands of students subsequently had their results cancelled, leading to appeals and judicial review applications. In MA Nigeria [2016] UKUT 450 (IAC) the Upper Tribunal noted that “As none of the computers or data media associated with the test centres involved in these cases is available, there is no information relating to the important issues of audit, log and configuration files and related time and date stamps.” Nevertheless this series of cases has so far concluded that the process of matching audio-files of test results to individual students was generally sound.
The presentation of electronic evidence is itself a challenging issue. Lawyers are used to working with “copies” of “original” documents, commonplace in the era of reprographic technology. But where the document is an electronic one, there is no paper “original”. Metadata may assist to establish the provenance of what is supplied to the court.
The evaluation of evidence is itself likely to be complex. Judicial associations such as the International Association of Refugee and Migration Judges (IARMJ) are looking into the subject with a view to producing guidelines on aspects of electronic evidence, such as the analysis of evidence from social media. The IARMJ working group has looked at issues such as the malleability, durability, and reliability of such evidence. Fraser J in Bates did his best to render matters more comprehensible by placing much of the technical detail in an Appendix. This still left the judgment numbering 1030 paragraphs.
Stephen Mason and others have written a valuable article endorsing a practical proposal for how a challenge to a system’s reliability might be handled in their Briefing Note: The legal rule that computers are presumed to be operating correctly – unforeseen and unjust consequences (SAS) beginning with a reasonable and proportionate search for documents which can reasonably be expected from any professionally managed system, followed by a more detailed survey in the event that the initial search raised questions as to the system’s management or reliability.
Mark Symes is a barrister at Garden Court Chambers and co-Director of HJT Training.
Photo by Centre for Ageing Better on Unsplash.
Leading experts in this field will be speaking at HJT Training’s course Computer Evidence in Court at the Offices of Hodge Jones & Allen on 2 October 2024 180 North Gower St, London NW1 2NB. Featuring Stephen Mason, Jonathan Bridge & David Bridge, with a guest speaker from the Post Office litigation: Lee Castleton, formerly a Yorkshire postmaster who was bankrupted by the legal costs enforced against him by the Post Office at an early stage in events. A free copy of Stephen Mason’s book Electronic Evidence and Electronic Signatures is provided for course delegates.
