Experts tell the New York Times that several techniques can increase the accuracy of police lineups. 1. Blind Administration: An investigator who shows the witness a photo lineup can influence the witness's response, even unintentionally. Departments can remedy this by having someone not familiar with the case run the lineup. In a variation, the investigator cannot see which images the witness is looking at. 2. Sequential Lineup: Show images one by one instead of all at once to avoid “relative judgment” — comparing the members of the lineup to one another for the best match, rather than selecting the image that most closely matches the witness's memory.
3. Good Fillers: The other people in the lineup should resemble the witness's description of the person who committed the crime so that the suspect does not stand out. 4. Low Pressure: Witnesses should be told that the suspect may or may not be in the lineup so they will not feel compelled to pick an image. Investigators should not congratulate witnesses for selecting a match or press them to make an identification. 5. Writing It Down: Witnesses are often somewhat uncertain of their choice at first and become more certain by trial. Recording the witness's level of certainty at the time of the identification helps prevent overselling the identification.