Testing encoding specificity and the diagnostic feature-detection theory of eyewitness identification, with implications for showups, lineups, and partially disguised perpetrators.

The diagnostic feature-detection theory (DFT) of eyewitness identification is based on facial information that is diagnostic versus non-diagnostic of suspect guilt. It primarily has been tested by discounting non-diagnostic information at retrieval, typically by surrounding a single suspect showup with good fillers to create a lineup. We tested additional DFT predictions by manipulating the presence of facial information (i.

Never forget a face: Verbalization facilitates recollection as evidenced by flexible responding to contrasting recognition memory tests.

Verbal facilitation occurs when describing a face improves its subsequent recognition; but there are several theoretical explanations debated in the literature. The results of the present studies support a relatively unrestricted, parsimonious theory that verbal facilitation occurs because describing a face supports recollection of several different facets of the face-viewing experience. This recollection is then demonstrated by flexibly responding to two competing types of recognition task demands.

Lineup fairness: propitious heterogeneity and the diagnostic feature-detection hypothesis.

Researchers have argued that simultaneous lineups should follow the principle of propitious heterogeneity, based on the idea that if the fillers are too similar to the perpetrator even an eyewitness with a good memory could fail to correctly identify him. A similar prediction can be derived from the diagnostic feature-detection (DFD) hypothesis, such that discriminability will decrease if too few features are present that can distinguish between innocent and guilty suspects. Our first experiment tested these predictions by controlling similarity with artificial faces, and our second experiment utilized a more ecologically valid eyewitness identification paradigm.

Searching for the sequential line-up advantage: a distinctiveness explanation.

Gronlund ( 2005 ) proposed that one factor leading to a sequential line-up advantage could be the greater likelihood of recollecting distinctive information about a perpetrator when using a sequential line-up. Since then questions have been raised about the robustness of the sequential advantage and the possible moderating role of line-up fairness and suspect position. We manipulated these factors as well as suspect/target distinctiveness in two experiments.

Exploring the sequential lineup advantage using WITNESS.

Advocates claim that the sequential lineup is an improvement over simultaneous lineup procedures, but no formal (quantitatively specified) explanation exists for why it is better. The computational model WITNESS (Clark, Appl Cogn Psychol 17:629-654, 2003) was used to develop theoretical explanations for the sequential lineup advantage. In its current form, WITNESS produced a sequential advantage only by pairing conservative sequential choosing with liberal simultaneous choosing.

Robustness of the sequential lineup advantage.

A growing movement in the United States and around the world involves promoting the advantages of conducting an eyewitness lineup in a sequential manner. We conducted a large study (N = 2,529) that included 24 comparisons of sequential versus simultaneous lineups. A liberal statistical criterion revealed only 2 significant sequential lineup advantages and 3 significant simultaneous advantages.

Lineup composition, suspect position, and the sequential lineup advantage.

N. M. Steblay, J.