Guilt status influences plea outcomes beyond the shadow-of-the-trial in an interactive simulation of legal procedures.

Abstract

Objective: More than 95% of criminal convictions in the United States are secured by guilty pleas. Our current understanding of the "deals" that lead so many to plead guilty is often tied to the shadow-of-the-trial (SoT) model, which posits that plea outcomes rely solely on the penalty discrepancy they offer (represented as: [trial conviction probability 3 trial sentence]plea sentence). This study compared the power of the SoT model to predict plea outcomes with two expanded models. Hypotheses: We hypothesized that the SoT model's power to predict whether defendants will accept a plea offer could be improved by expanding the model. The first expanded model added a main effect of guilt status, presuming that regardless of penalty discrepancy, the guilty will be more likely to accept plea offers than the innocent. The second expanded model added an interactive effect of guilt status with penalty discrepancy: although greater discrepancies would increase both true and false guilty pleas, the magnitude of the effect would be greater among the innocent. Method: We recruited student (N = 596, 45.8% female, M = 19.9 years old) and nonstudent (N = 525, 45.1% female, M = 30.9 years old) adult samples to participate in a 2 (guilt status: innocent or guilty) 3 3 (conviction probability: 20%, 50%, or 80%) 3 3 (plea discount: 6, 12, or 18 months) mixed design. All participants experienced two crime scenarios in a counterbalanced order. We randomized the manipulated variables for each scenario such that each participant was administered two of eighteen potential conditions. Results: As hypothesized, the predictive power of the SoT model was significantly improved by expanding it to include guilt status-guilty participant-defendants were consistently more likely to accept the plea offer than innocent participant-defendants. However, an interactive effect of guilt status with penalty discrepancy did not significantly improve the power of the SoT model to predict plea outcomes. Conclusions: The power of the SoT model could be significantly improved by incorporating guilt status as a predictor. Although there are many times at which guilt status is unknown, the acknowledgment of a separate effect of guilt status has important policy implications for the plea process. Public Significance StatementThe dominant model of plea decision-making has posited that guilty pleas occur "in the shadow-of-thetrial," rendering actual guilt status largely irrelevant. The current research demonstrates that guilt status does meaningfully impact plea decisions. Future research can now focus on ways of capitalizing upon the differences between the innocent and guilty to reform the system of pleas in a way that preserves a high true guilty plea rate while better insulating the innocent from the pressure to plead guilty falsely.

Innocence in the shadow of COVID-19: Plea decision making during a pandemic.

“…Guilty participants were significantly more likely to accept the plea offer than innocent participants. This finding is consistent with previous research demonstrating a significant effect of guilt, and confers further support for extending the shadow-of-the-trial model to include guilt status as a predictor (Wilford et al, in press). That said, the false guilty plea rate even in the no COVID-information condition was still substantial.…”

“…Many experimental studies have found that guilty defendants are generally more likely to plead guilty than innocent ones (Redlich & Shteynberg, 2016; Schneider & Zottoli, 2019; Tor et al, 2010; Wilford, Wells, & Frazier, 2021; Wilford et al, in press). Accordingly, we predicted that guilty participant-defendants would plead guilty more frequently than innocent participants (Hypothesis 1 [H1]).…”

“…Essentially, it posits that plea offers will be accepted when the plea sentence is less than the expected value of the trial (which is calculated by multiplying the trial sentence by the probability of conviction). This model has been regularly criticized for being overly simplistic (Bibas, 2004; Redlich et al, 2017; Wilford et al, 2019), with recent research showing that there is room to improve its predictive power (Wilford et al, in press). Few alternatives to the shadow-of-the-trial model have emerged, and those that have also lack a clear method to account for the direct impact of other external variables on plea outcomes (e.g., fuzzy trace theory, Helm & Reyna, 2017; the trial penalty model, McCoy, 2005).…”

Charged up and anchored down: A test of two pathways to judgmental and decisional anchoring biases in plea negotiations.

“…Finally, the finding that mock defendants in Experiment 1 regarded the aggravating evidence as overall stronger than the mitigating evidence whereas the opposite was true of attorney–client pairs in Experiment 3 suggests that the modality of asynchronous vignette studies may lead to qualitatively different results than more interactive paradigms. This discrepancy suggests a need for more immersive paradigms that may more accurately reflect the decision-making of truly self-interested decision-makers (see also Wilford et al, 2021).…”

The paradox of conviction probability: Mock defendants want better deals as risk of conviction increases.

“…Clarifying potential differences in the ways that innocent and guilty defendants arrive at probability estimates and how such information affects their plea acceptance thresholds is an important next step. While studying false guilty pleas can be challenging, several investigators are working on methodologies that may make it easier to generate false guilty pleas in the laboratory without sacrificing the use of real-world scenarios (Frazier & Gonzales, 2020; Wilford et al, 2020).…”