Plea bargaining

Opinion. The Injustice of the Plea-Bargain System
by: Lucian E. Dervan
Dec 04, 2015
Click here to view the full article on WSJ.com

TOPICS: Decision Making Under Uncertainty, Law and Economics

SUMMARY: Fearing harsh sentences, far too many defendants are pleading guilty and forfeiting their right to trial.

CLASSROOM APPLICATION: The article offers a good case to analyze decision making uncertainty. Students can examine how the length of the possible sentence based on a trial, the probability distribution over possible sentences, and the length of a plea deal affect whether an accused person accepts a deal. The accused's degree of risk aversion also affects the decision. Students can also discuss the ethics of plea bargain deals and of innocent defendants accepting deals.

QUESTIONS: 
1. (Introductory) Why are defendants overwhelmingly accepting plea deals? Discuss two issues: whether the police and judicial system is functioning well in the sense that mostly those who are arrested for crimes are in fact guilty; and whether plea deals lengths are set so that it is in the best interest of most defendants, whether guilty or not, to accept the deals.

2. (Introductory) Is it ethical that in the U.S. judicial system an overwhelming majority of defendants are accepting plea deals? What criterion should be used to evaluate whether a judicial system is ethical?

3. (Advanced) Consider the following scenario of an individual accused of a crime and facing the possibility of a trial. Let x represent the length in years of a prison sentence. The individual's utility function is U(x) = sqrt (10-x). If the person chooses to take his or her case to trial, the possible sentences are 0 (if the person is acquitted) and 10 years (if the person is found guilty). The probability of being found guilty is 7/10. What is the expected value in terms of years in prison of going to trial? What is the expected utility of going to trial? Suppose the accused is offered a plea deal of 8 years. Would the person accept the deal? What is the greatest time in prison that the person would accept as a plea deal?

4. (Advanced) Is the person risk averse with respect to the number of years in prison? How does the greatest plea deal the person would accept compare to the expected value in terms of prison years of going to trial? Discuss the relationship between risk aversion and the comparison of these two values?

Reviewed By: James Dearden, Lehigh University