Evolution of the empirical and theoretical foundations of eyewitness identification reform

Abstract

Scientists in many disciplines have begun to raise questions about the evolution of research findings over time (Ioannidis in Epidemiology, 19, 640-648, 2008; Jennions & Møller in Proceedings of the Royal Society, Biological Sciences, 269, 43-48, 2002; Mullen, Muellerleile, & Bryan in Personality and Social Psychology Bulletin, 27, 1450-1462, 2001; Schooler in Nature, 470, 437, 2011), since many phenomena exhibit decline effects-reductions in the magnitudes of effect sizes as empirical evidence accumulates. The present article examines empirical and theoretical evolution in eyewitness identification research. For decades, the field has held that there are identification procedures that, if implemented by law enforcement, would increase eyewitness accuracy, either by reducing false identifications, with little or no change in correct identifications, or by increasing correct identifications, with little or no change in false identifications. Despite the durability of this no-cost view, it is unambiguously contradicted by data (Clark in Perspectives on Psychological Science, 7, 238-259, 2012a; Clark & Godfrey in Psychonomic Bulletin & Review, 16, 22-42, 2009; Clark, Moreland, & Rush, 2013; Palmer & Brewer in Law and Human Behavior, 36, 247-255, 2012), raising questions as to how the no-cost view became well-accepted and endured for so long. Our analyses suggest that (1) seminal studies produced, or were interpreted as having produced, the no-cost pattern of results; (2) a compelling theory was developed that appeared to account for the no-cost pattern; (3) empirical results changed over the years, and subsequent studies did not reliably replicate the no-cost pattern; and (4) the no-cost view survived despite the accumulation of contradictory empirical evidence. Theories of memory that were ruled out by early data now appear to be supported by data, and the theory developed to account for early data now appears to be incorrect.

The impact of fillers on lineup performance

“…Our simulations revealed that fillers can have a detrimental effect on sequential lineup performance, thereby restricting the generalizability of filler siphoning theory. Notably, our simulations provide a theoretical rationale supporting the empirical conclusion (see Clark, Moreland, & Gronlund, 2014 ) that sequential lineups typically result in worse performance than simultaneous lineups. The presence of fillers can enhance simultaneous lineup performance, but the presence of fillers can harm sequential lineup performance.…”

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

“…In other words, the goal of our experiments is to utilize a theory of underlying psychological discriminability to make predictions about empirical discriminability. Other researchers have noted that it is critical to ground eyewitness ID research in theory (e.g., Clark, Benjamin, Wixted, Mickes, & Gronlund, 2015; Clark, Moreland, & Gronlund, 2014).…”

“…Moreover, despite the historical advocacy for a description-matched approach, to date there are few direct tests of description-matched versus suspect-matched fillers. Lastly, Clark et al (2014) found that the original accuracy advantage for description-matched fillers has declined over time. One of our goals is to determine if the advantage is real.…”

Do sequential lineups impair underlying discriminability?

“…While the finding of equal underlying discriminability is not consistent with DFDT, the difference in response criteria was consistent with the view that a sequential lineup produces a higher diagnosticity ratio. It is now widely accepted that sequential presentation leads to more conservative responding than simultaneous presentation (Clark, 2012 ; Clark, Moreland, & Gronlund, 2014 ; Wells, 2014 ; Wixted & Mickes, 2014 ). The apparent success of the modelling approach employed by Palmer and Brewer ( 2012 ) has also led researchers to use SDT-INT to examine other aspects of the sequential lineup (Carlson, Carlson, Weatherford, Tucker, & Bednarz, 2016 ; Horry et al, 2015 ; Horry, Palmer, & Brewer, 2012 ).…”