Without the first precaution, they explained, sequential lineups might be even more vulnerable to manipulation than simultaneous lineups are. John Turtle, a panel member and a psychologist at the Ryerson Polytechnic Institute, in Toronto, believes that he has a high-tech solution to all those concerns. He has developed computer software that purports to take the bias out of the photo-spread lineups, which constitute about 80 percent of those in the United States and virtually all of those in Canada. All a police investigator would need to do is scan a photo of the suspect into a computer and sit the witness down in front of the screen. The machine would then automatically choose photos of others who match the witness's description from a large database, and offer standardized, neutral instructions that wouldn't nudge the witness toward a particular response.
Psychologists deny they are imputing bad faith to police investigators.
It's human nature, they say, to want your results to match your expectations. The scholars are simply urging police officers to treat their procedures for handling witnesses with all the care of scientific experiments. How you go about collecting that evidence and preserving it and analyzing it is absolutely vital.