[1] The use of digital evidence has increased in the past few decades as courts have allowed the use of e-mails, digital photographs, ATM transaction logs, word processing documents, instant message histories, files saved from accounting programs, spreadsheets, web browser histories, databases, the contents of computer memory, computer backups, computer printouts, Global Positioning System tracks, logs from a hotel’s electronic door locks, and digital video or audio files.
Digital evidence is often attacked for its authenticity due to the ease with which it can be modified, although courts are beginning to reject this argument without proof of tampering.
As courts became more familiar with digital documents, they backed away from the higher standard and have since held that "computer data compilations… should be treated as any other record."
[8] Therefore, establishing a clear chain of custody and demonstrating that the evidence presented is unchanged from its original state is crucial.
To address this issue, commercial software technology solutions have been developed to preserve digital evidence in its original form and authenticate it for admissibility in court disputes.
In the United Kingdom, examiners usually follow guidelines issued by the Association of Chief Police Officers (ACPO) for the authentication and integrity of evidence.
Principle 3: An audit trail or other record of all processes applied to digital evidence should be created and preserved.
These guidelines are widely accepted in courts of England and Scotland, but they do not constitute a legal requirement and their use is voluntary.
In Aguimatang v. California State Lottery, the court gave near per se treatment to the admissibility of digital evidence stating "the computer printout does not violate the best evidence rule, because a computer printout is considered an ‘original.’" 234 Cal.