The harm that judges do – misunderstanding computer evidence: Mr Castleton’s story

‘an affront to the public conscience’

  • Paul Marshall


The reliability of computer systems, and the reliability of documents produced by computers, is important. There is a widely held perception that computers are fundamentally reliable. Further, it is commonly assumed that most computer errors are readily detectable or otherwise the result of user ‘input’ error. Since 1997 the courts have applied the presumption of the proper functioning of machines to computers. This article considered the case of Lee Castleton to illustrate that this presumption can have a devastating effect when applied.

Index words: software, electronic evidence, computer evidence, presumption of reliability