The Diagnosticity of a Lineup Should Not Be Confused With the Diagnostic Wue of Nonlineup Evidence

We argue that a lineup is diagnostic to the extent that it reveals information from recognition memory that was not available from the eyewitness^ recall memory Accordingly, lineup diagnosticity is denned as the probability that an innocent suspect is identified by the witness when lineup members resemble the eyewitness's prelineup description. Navon (1990) argued that this definition underestimates lineup diagnosticfty because it ignores other evidence against the accused. We argue that these other forms of evidence, which Navon calls ecological parameters, have diagnostic utility but should not be confused with the diagnostic value of the lineup itself. Furthermore, although Navon correctly noted that experimenters' selections of innocent suspects in eyewitness experiments are not random, we argue that police select suspects in a similarly nonrandom manner.