X-rays

“[courts] treated X-ray evidence as an exception to the doctrine, necessitated by the unavailability of direct eyewitness testimony. . . . In short, the courts treated X-ray images as substantive evidence of the conditions revealed by them, while still discounting regular photographs by admitting them only as illustrations” (Golan, 488). . . . the X-ray admissibility procedure was gradually recognized as being applicable to regular photography too” (489). . . . The basis on which X-ray images were admitted was extended to include not only the observation powers of the verifying witness, but also the reliability of the mechanical process that produced them. The essential relationship underlying the doctrine of illustrative evidence – the association between the visual evidence and the witness whose perceptions and knowledge it purported to represent – was severed” (489). . . . The alternative approach came to be known as the ‘silent witness’ doctrine.