Framing Biases in Plea Bargaining Decisions in Those With and Without Criminal Involvement: Tests of Theoretical Assumptions

Abstract

About 95% of criminal convictions in the United States are obtained through plea decisions, a growing global practice. Courts justify these convictions based on defendant choice—defendants, as rational agents, can freely choose to plead guilty or go to trial. However, a fundamental axiom of rational choice—descriptive invariance—has never been effectively tested for plea decisions. To test this axiom, we manipulated gain–loss framing of plea options. The shadow-of-trial model, the leading theory of plea decision-making, is predicated on expected utility theory which is in turn predicated on the invariance axiom; if the axiom is falsified, the entire structure collapses. Thus, framing effects are important as a test of fundamental assumptions undergirding practice and as an empirical phenomenon revealing effects of context. We tested framing effects in students and community members including those with criminal involvement for whom plea bargaining has personal relevance. Varying subtle changes in wording of outcomes, we produced pronounced differences in choices to accept a plea rather than proceed to trial. These framing effects were robust to age, sex, educational attainment, risk propensity (DOSPERT and sensation seeking), and loss aversion. Perceived fairness of the legal system increased acceptance and risk propensity decreased it (each about 32%). However, controlling for those effects, loss (compared to gain) framing increased the odds of going to trial by 664%. Criminal involvement did not account for additional variance. These results are consistent with prospect theory and fuzzy-trace theory, but they challenge the legal theory of bargaining in “the shadow of trial.”