Computer Records Evidence
Reviewed 30 june 2017
Rebuttable Presumption of Correct Functioning of a Computer
Prior to the repeal of section 69 of the Police and Criminal Evidence Act 1984 by section 60 of the Youth Justice and Criminal Evidence Act 1999, it was necessary to prove that a computer was operating properly and was not used improperly before any statement in a document produced by the computer could be admitted in evidence.
Computer evidence must now follow the Common Law rule, that a presumption will exist that the computer producing the evidential record was working properly at the material time and that the record is therefore admissible as real evidence.
That presumption can, however, be rebutted if evidence to the contrary is adduced. In that event it will be for the party seeking to produce the computer record in evidence to satisfy the court that the computer was working properly at the material time. For detailed guidance as to the law, see <Archbold 9-11 9-15>.
Information obtained from a computer, whether printed out or read from a display, may be divided into three categories. For more detail see <Archbold 9-11 9-13>.
The first is where the computer has been used simply as a calculator to process information.
The second is information the computer has been programmed to record.
The third category is information recorded and processed by the computer which has been entered by a person, whether directly or indirectly. It is only information from a computer in this third category which is hearsay: to be admissible, it must be brought within one of the exceptions to the rule against hearsay.
Where the statement in a document produced by a computer contains hearsay evidence, it is also necessary to comply with the provisions of the Criminal Justice Act 2003 especially sections 127 and 129 see <Archbold 11-45 to 11-59>
The repeal of section 69 of the Police and Criminal Evidence Act 1984 will be particularly helpful in cases where chains of linked computers are involved, for example internet fraud.
The House of Lords has held that a store detective is competent to produce till rolls produced by a stores computer where the store detective was familiar with the operation of the tills and can say that the store had no difficulties caused by the operation of the computer.