Best evidence rule

Definition
The best evidence rule generally requires a party seeking to prove the contents of a writing, recording, or photograph to introduce the original writing, recording, or photograph unless an exception applies.

Computer printouts
Even though a printout of a computer-stored record might technically not be viewed as an original (especially because the “original” data are simply a string of 1s and 0s), the best evidence rule does not present a problem if the printout accurately reflects the data. In recognition of the demands of practicality and common usage, the Federal Rules of Evidence provide that “[i]f the data are stored in a computer or similar device, any printout or other output readable by sight, shown to reflect the data accurately, is an ‘original’” This principle applies even if the duplicate originals have an inconsistent appearance (e.g., different fonts or margins).