The Eyewitness

Before a witness can recall a complex incident, the incident must be accurately perceived at the onset; it must be stored in memory. Before it can be stored, it must be within a witness's perceptual range, which means that it must be loud enough and close enough so the the ordinary senses pick it up. If visual details are to be perceived, the situation must be reasonably well illuminated. Before some information can be recalled, a witness must have paid attention to it. But even though an event is bright enough, loud enough, and close enough, and even though attention is being paid, we can still find significant errors in a witness's recollection of the event, and it is common for two witnesses to the same event to recall it very differently.

Elizabeth Loftus, Eyewitness Testimony, 1979