Disentangling the Effects of Plea Discount and Potential Trial Sentence on Decisions to Plead Guilty

A plea deal involves two important components: plea discount and potential trial sentence (“PTS”). This study seeks to determine whether a defendant’s decision to plead guilty stems from the threat of a more severe punishment, the size of the plea discount, or a mixture of the two. The results indicated that culpability, PTS, and the size of the plea discount all had effects on a defendant’s decision to accept or reject a plea, with plea discount having the most significant effect. Specifically, guilty defendant-participants were more likely to plead guilty than innocent ones in all conditions. Additionally, rates of plea acceptance increased as the size of the plea discount increased. PTS did not have as significant of an effect on the decision to plead. Notably, plea rates were higher when the PTS was 5 years as opposed to 25 years, indicating that the attractiveness of an offer may be higher for defendants facing a shorter PTS. Moreover, although a majority of the participants had outcome-oriented rationales for the decision to accept or reject a plea, value-oriented rationales began to emerge when the size of the plea discount increased.

“This investigation yielded three important findings: (1) Plea discount and potential trial sentence exerted opposite and independent effects on plea decisions, (2) these effects were present for both guilty and innocent defendants, and, (3) of the two, it was size of the plea discount that appeared to be most important.” p. 300