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Jury Trials: Opposed

01 July 2009

The jury trial system is so complicated and expensive that it forces most defendants to accept plea bargains arranged in secret. In the relatively few cases that go to trial, jurors are often considering technical issues beyond their aptitude. Peter J. van Koppen is professor of legal psychology at Maastricht University Law School and Free University Law School, both in the Netherlands. This article appears in the July 2009 issue of eJournal USA, “Anatomy of a Jury Trial.”

By Peter J. van Koppen

One day you visit your general physician. You are greeted there by a panel of 12 individuals. The one person who apparently is the chairwoman cheerfully tells you that this panel is replacing your doctor for the next month. With confidence she adds: “Do not worry, dear, most of what doctors do is common sense anyway.” What would you do?

In fact, the chairwoman is right: Most of what doctors do is common sense. But an important part is not. And that part is the vital part of your doctor’s work. Even more vital, maybe, is that your doctor is able to distinguish the odd difficult case and the dangerous condition of a patient from the average run-of-the-mill disease.

The defendant who enters the courtroom and who has decided not to plea bargain is confronted with such a cheerful bunch of jurors. They are there to evaluate the evidence and decide whether the defendant is guilty or not. The question is whether such a jury is better than the alternative. What I mean by alternative, I shall discuss shortly.

For sure, everybody would prefer a general physician with a diploma to the general physician-jury, and that holds for almost all professionals. So a first question is: Is decision-making or fact-finding in criminal cases such that it can be done by laypersons? In order to answer that question, let me dissect the problem that faces the jury in a criminal trial. A jury must make a decision about the truth. American lawyers reply immediately that criminal trials are not about the truth, but about a certain version of the truth: Which party has the better argument about the truth?

Either way, the work to be done by a jury does not differ much from what any scientist has to do. A scientist has to make inferences about states of affairs that cannot be observed directly, inferring from evidence that can be observed. And that is precisely what a jury has to do: make a decision about the guilt of the defendant based on the evidence presented at trial. That is a scientific enterprise that surpasses the intellectual aptitude of most laypersons who are called to jury duty.

Proponents of the jury tend to use the seminal study by Harry Kalven and Hans Zeisel from 1966 here. In a large number of cases, Kalven and Zeisel, while the jury was in the jury room deliberating, asked the single judge presiding over a trial what he would decide. They found that in most cases the judges would have rendered the same verdict as the jury somewhat later returned.

Training Matters

That study warrants some comments. As with the example of the physician, the professional judge and the jury may agree most of the time, but that does not mean that they agree in the most important cases, the cases where decision making on the facts of the case is in some way difficult and where knowledge and training would matter.

Why would we turn to the judge to assess the quality of jury decisions? That assumes two things: that the judges are so good that they can be used as a criterion for the evaluation of the jury, and that law matters for the decision problem faced by the jury. The latter point is a common misconception. The jury decision is a purely factual decision that takes the form of a scientific decision. Most important, the law has nothing to do with that decision. The decision may be embedded in all kinds of legal rules – for instance about what evidence can be presented to the jury or can enter the decision — but that does not make the decision itself a legal decision. Jury proponents then would argue that the standard of decision making in criminal trials, beyond a reasonable doubt, is a legal rule. That is not so. It is the same kind of decision rule that is applied widely in science, just with a different name. In psychology, for instance, the same decision rule is called significance level.

And single judges are indeed the wrong kind of people to use as a criterion for scientific decision making. First of all, a panel of judges would be a fairer comparison. In most countries, cases without a jury are decided by panels of three or five judges. But, secondly, aren’t judges as much laypersons on factual decision making as juries? Those who enter law school usually do that because they do not like scientific thinking or hate math or detest doing experiments. And surely legal thinking considerably departs from scientific thinking.

Judges, as such, thus are not better qualified than jurors for fact-finding unless they are trained. And in countries with professional judges, the judges are trained. In fact, when I serve as an expert witness in my small country, I often encounter courts in which one or more judges have been in my class where I taught them about witness statement, identification, and evaluation of evidence. How could proponents of jury trials argue that training does not matter in solving the kind of complicated problems in some criminal cases? Why do they ignore that there are more known miscarriages of justice in jury countries such as the United States and Great Britain than in continental nonjury countries?

Other Disadvantages

A system with jury trials has some additional disadvantages that are seldom discussed. First, a jury trial is more complicated than a bench trial (a trial where a judge or panel of judges reaches a verdict). That places higher demands on the defense attorney. Jury trials require better lawyers, but most defendants in the United States are too poor to hire a good-quality attorney. In countries with bench trials, a not-very-good attorney is a lesser disadvantage for the defendant.

The jury trial also is very time consuming and labor intensive. In fact, it is so expensive that a jury system can only be maintained if the vast majority of cases are dealt with differently. In the United States that occurs through plea bargaining, a negotiated agreement between prosecution and defense with a marginal check by a judge. In practice this is a system where most cases end in a way that nobody really has evaluated the evidence, without public scrutiny and with disproportionate power for the prosecution.

In short: In the jury system most cases are handled in secret, and a minute number of cases are decided by little groups of people who apply their common-sense ideas to complicated problems beyond their training.

The opinions expressed in this article do not necessarily reflect the views or policies of the U.S. government.