Law Report: Computer evidence did not need expert backing: Regina v Shephard - House of Lords (Lord Griffiths, Lord Emslie, Lord Roskill, Lord Ackner and Lord Lowry), 16 December 1992

A party in criminal proceedings who sought to rely on statements in a document produced by a computer, could discharge the burden under section 69(1) of the Police and Criminal Evidence Act 1984, of showing that the computer had been operating properly at the material time, without calling a computer expert. It was sufficient for a person familiar with the operation of the computer to give oral evidence of its reliability.

The House of Lord so ruled, on an issued certified by the Court of Appeal as a point of law of general public importance, and dismissed an appeal by Hilda Shephard against the decision of the Court of Appeal (Criminal Division) ((1991) 93 Cr App R 139) who dismissed her appeal against conviction at St Albans Crown Court on 27 October 1989, for theft contrary to section 1(1) of the Theft Act 1968.

Christopher Llewellyn-Jones QC, and Robert Leonard (Ellis & Hancock, Watford) for the defendant; Brian Barker and Esther Kayman (CPS) for the Crown.

LORD GRIFFITHS said that the defendant had been arrested at her home on 17 March 1989. In her car were found goods from Marks & Spencer worth pounds 78.36. She had no receipt. She said that she had bought the goods at Marks & Spencer at St Albans, and that when she returned to her car the bags had split, so she transferred the shoppping to a bag of her own. She said she never kept receipts and denied stealing the goods.

The principal prosecution evidence was given by a store detective employed by Marks & Spencer at St Albans, who said she had removed all the till rolls from the tills at that store for 17 March, and explained that all the tills were connected to a central computer which fed in the date, time, customer number and till number on each roll. Each item of clothing had upon it a seven-figure numbered label, known as the Unique Product Code or UPC. The till operator punched in the UPC, which then registered the appropriate price. Each food item had a price on it and the operator punched in the price of each item on the till.

She had examined all the till rolls for 17 March and said there was no record on them of the items found in the car. It was quite apparent from the store detective's evidence that she was thoroughly familiar with the operation of the tills and the computer, albeit that she did not pretend to any technical understanding of the computer's operation.

The appellant submitted that the till rolls should not have been admitted in evidence because the store detective's evidence did not satisfy section 69, which provided: '(1) In any proceedings, a statement in a document produced by a computer shall not be admissible as evidence of any fact stated therein unless it is shown . . . (b) that at all material times the computer was operating properly . . .'

The appellant's principal argument began with the proposition that the store detective was not 'a person occupying a responsible position in relation to the operation of the computer' within paragraph 8(d) of Schedule 3 to the 1984 Act, and, therefore, was not qualified to sign a certificate for the purpose of providing proof of the matters contained in section 69(1). His Lordship accepted that. Although the store detective understood the operation of the computer and could speak of its reliability, she had no responsibility for its operation.

His Lordship could not accept the next step in the appellant's argument, which was that oral evidence was only acceptable if given by a person who was qualified to sign the certificate. The appellant insisted that evidence must be given by someone who had responsibility for the operation of the computer. Proof that the computer was reliable could be provided in two ways - either by calling oral evidence or by tendering a written certificate in accordance with the terms of paragraph 8 of the Schedule 3, subject to the power to the judge to require oral evidence.

It was understandable that if a certificate was to be relied upon it should show on its face that it was signed by a person who, from their job description, could confidently be expected to be in a position to give reliable evidence about the operation of the computer. This enabled the defendant to decide whether to accept the certificate on its face value or ask the judge to require oral evidence which could be challenged in cross- examination.

A defendant seeing a certificate signed by a store detective would not necessarily assume that such a person was familiar with the operation of the computer or had any responsibility for it and might well challenge the certificate. But it did not follow that a store detective could not, in fact, give evidence that showed she was fully familiar with the operation of the store's computer and could speak of its reliability.

Documents produced by computers were an increasingly common feature of all business and more and more people were becoming familiar with their uses and operation. Computers varied immensely in their complexity and in the operations they performed. The nature of the evidence to discharge the burden of showing that there had been no improper use of the computer, and that it was operating properly, would inevitably vary from case to case.

In the vast majority of cases, it would not be necessary to call an expert and would be possible to discharge the burden by calling a witness who was familiar with the operation of the computer, in the sense of knowing what the computer was required to do, and could say that it was doing it properly.

In this case, the store detective was fully qualified to give the evidence required by section 69, even though she was not a computer expert.

LORD EMSLIE, LORD ROSKILL, LORD ACKNER and LORD LOWRY agreed.

Paul Magrath, Barrister