Juries and Judges’ Instructions

When a jury trial is conducted, community members who typically have no special legal training or knowledge are called on to serve as jurors. During the trial, the judge instructs jurors as to the relevant law and the procedures to be used to determine an appropriate verdict in the case. Unfortunately, jurors do not always render a verdict congruent with the law. Frequently, jurors misunderstand a large portion of the instructions that are presented to them. In some cases, jurors may also decide to disregard the instructions they have been given. A variety of factors contribute to instruction ineffectiveness, including the language used to convey the instructions, jurors’ education level, and jurors’ preexisting “commonsense” beliefs about the law. A number of proposed improvements to the instruction process, such as rewriting the instructions, changing the timing of delivery of instructions, providing written instructions, and providing a special verdict form or flow chart/decision tree, have been empirically evaluated. The effectiveness of each of these potential solutions is discussed.

Purpose of Instructions

During a trial, the judge delivers relevant substantive and procedural instructions to jurors. Substantive instructions refer to laws that apply to the specific case at hand (e.g., the definition of first- and second-degree murder, manslaughter, sexual assault, and arson; relevant civil laws, etc.). Procedural instructions refer to the general duties of jurors and are relevant across cases (e.g., legal thresholds such as “reasonable doubt” in criminal cases or “clear and convincing evidence” in most civil cases in the United States, the decision rule to be used—either a unanimous or a majority decision, concepts such as burden of proof, etc.).

Development of Pattern Instructions

Historically in the United States, judges would create jury instructions on a case-by-case basis with input from the attorneys involved in the case. However, this process was time-consuming and led to frequent objections on the ground that the relevant law had been incorrectly explained to jurors. In addition, there was not always consistency in the instructions used in cases of a similar nature. Finally, there was concern that jurors did not understand the instructions they were presented with due to the complexity of the law and because judges were forced to focus their attention on delivering instructions that were legally accurate rather than on explaining the law in a manner that jurors could easily understand, to avoid having cases appealed.

To resolve these problems, prewritten “pattern jury instructions” were developed. Pattern instructions are instructions that have been preapproved by relevant sources (legislatures, state bars, commissions) and can be used repeatedly. In 1938, California was the first state to adopt a set of pattern instructions. This practice quickly spread to jurisdictions across the United States at both the state and the federal level.

Pattern instructions were efficient for judges to use, reduced the number of appeals due to the use of erroneous instructions, and successfully ensured that jurors in similar cases heard consistent instructions. However, a well-established body of social science research has demonstrated that jurors still have considerable difficulty in understanding the law when pattern instructions are used.

Jury Instruction Comprehension Rates

Instruction comprehension problems have been found in jurisdictions throughout the United States and in other countries that use laypersons as jurors (e.g., Canada, New Zealand, Australia, Scotland, and England). Many studies have found that jurors typically understand a little more than half the instructions they are presented with and that in some cases there is no difference in comprehension rates between participants who receive pattern instructions and those not instructed at all. Some studies have found comprehension rates below 40%, and some have found comprehension rates in the 70% to 80% range. This variability may be due in part to the measure used to assess comprehension, with higher rates obtained when True/False or other multiple-choice recognition questions are used and lower rates when participants are asked to paraphrase instructions.

Comprehension problems exist for both substantive and procedural instructions. In terms of substantive law, a variety of criminal instructions have been shown to be problematic, including those on murder, assault, robbery, theft, and insanity. For example, research has shown that about one third of jurors are unable to articulate that intent is an essential part of first-degree murder. In addition, other research has shown that jurors are not sensitive to the subtle, but important, differences between different insanity standards (i.e., the M’Naghten Standard, the American Law Institute standard, and the Guilty but Mentally 1ll standard). Instead, jurors tend to use their own beliefs about insanity in their decision making.

Death penalty instructions appear to be particularly problematic to jurors. In death penalty cases, jurors are typically asked to weigh aggravating factors (specific aspects of the crime that must be present to sentence a defendant to death) against any mitigating factors (aspects of the crime or the defendant’s life that make life imprisonment an appropriate verdict). Although the concept of aggravation appears to be reasonably well understood by jurors, mitigation (a critical safeguard that prevents the defendant from being unjustly executed) is not. Jurors sometimes confuse the factors as well (i.e., erroneously believe a mitigating factor to be an aggravating factor).

Research has indicated that jurors have considerable difficulty in comprehending a variety of concepts from civil trials, such as negligence and liability, and have difficulty in determining appropriate damage awards as a result. Some problems associated with civil instructions are likely a result of the complexity of civil law. Difficulties with civil instructions may also occur because jurors are less familiar with civil legal standards than criminal law concepts (as civil issues are portrayed less frequently in news reports and fictional legal stories presented on television, in films, and in books). In addition, in the United States, civil jurors are typically given minimal guidance as to how abstract concepts such as pain and suffering should be transformed into specific monetary amounts for damages.

Procedural instructions are also problematic for jurors. Some research has shown that jurors do not fully comprehend the meaning of presumption of innocence and burden of proof in criminal cases. There is confusion in the minds of jurors as to whether the burden of proof rests entirely on the prosecution and the defendant does not have to present any evidence.

In addition, jurors do not appear to have a complete understanding of the different “standards of proof.” The standard of proof is the level of certainty necessary for a fact finder (i.e., the jury) to find that charges against a defendant in a criminal case or the claims against a defendant/respondent in a civil case are true. In the United States, “beyond a reasonable doubt” is the standard used in criminal trials. Individuals in the legal community have estimated this standard to mean requiring approximately a 90% certainty of guilt. It is the highest standard of proof required, reflecting the belief that it is far worse to convict an innocent person than to acquit a guilty one, yet absolute certainty need not be achieved for a conviction. “Preponderance of evidence” is the standard of proof used in most civil cases and requires that the plaintiff establish a certainty above 50% that the allegations against a defendant are true. In addition, in cases of deprivation of liberty, such as civil commitment, denaturalization, deportation, and termination of parental rights, the standard of “clear and convincing evidence” is also used. This third standard is intended to be an intermediate threshold that falls between the other two and has been interpreted as requiring a certainty level between 67% and 75%. Although some research has shown that jurors provide estimates of the meaning of reasonable doubt that are close to those given by members of the legal community, there is still considerable variability in the estimates provided. In addition, jurors express considerably more variability (reflecting greater uncertainty) when asked to estimate the meaning of the preponderance of evidence and clear and convincing evidence standards. Courts do not typically elaborate on the meaning of standards of proof when jurors are instructed. In cases where definitions of the concepts are given, the explanations typically do not shed much light on the concepts (e.g., for reasonable doubt: a doubt “that is not trivial or imaginary” or a doubt “that would cause a reasonable man to hesitate in making an important decision”).

Instructions that caution jurors as to how to use evidence are also problematic. For example, some research has shown that jurors exposed to eyewitness testimony cautionary instructions (commonly known as “Telfaire” instructions) are no more sensitive to the problems associated with eyewitness testimony than jurors not given instructions. Periodically, the judge must instruct jurors to ignore inadmissible information that they have heard in court or in the form of pretrial publicity. These types of instructions have been typically shown to be ineffective. In some cases, jurors may actually pay more attention to evidence that has been ruled as inadmissible than if the judge had said nothing at all about it. This tendency has been termed the “backfire effect” and may be the result of either a sense of resistance (i.e., reactance) building up in jurors because they feel that their freedom to consider the evidence is being threatened or cognitive factors causing a person to pay more attention to information that he or she is actively trying to ignore.

Factors Affecting Instruction Effectiveness

A number of factors have been identified that affect the overall effectiveness of instructions. Comprehension issues are a primary problem and result from the language used to convey the instructions. As previously noted, historically, the focus of instructions has been on stating the law in a legally accurate manner rather than on creating instructions that are designed to maximize comprehensibility. In addition, this problem may be compounded in complex trials in which difficult legal concepts must be explained and a greater amount of instructions must be given. Education level has also been consistently shown to relate to instruction comprehension, with higher instruction comprehension rates found among well-educated jurors, although a number of researchers have found that even law students have difficulty in comprehending the instructions they are presented with.

As previously mentioned, in certain cases, jurors may decide to ignore the instructions they are given. This may happen in cases where a judge rules certain information as inadmissible. In addition, jurors may ignore the law and decide that even though a defendant has broken the law (as they understand the law to be), it would be morally wrong to render a conviction, because the defendant did not violate the spirit of the law or because the law is viewed to be unjust. This phenomenon is known as “jury nullification.”

Finally, jurors’ beliefs about the law may also interfere with the effectiveness of instructions. There is evidence that jurors tend to rely on their own beliefs regarding the meaning of legal concepts rather than on the specific instructions they are given. This process is known as using “commonsense justice.” Jurors may use commonsense justice in their decision making because their beliefs regarding certain legal concepts such as insanity may be particularly strong or because jurors are forced to rely on whatever relevant concepts they possess when given instructions that are unclear.

Improving the Jury Instruction Process

Social science researchers have examined a variety of techniques for improving jurors’ comprehension levels for instructions. The most effective technique appears to be rewriting the instructions using general psycholinguistic principles. A variety of research teams across the United States have successfully improved comprehension rates using this approach, with improvement gains between 20% and 30% often detected. It is unclear whether additional revisions to instructions would lead to even higher gains.

In the process of revising instructions, researchers have focused on revisions such as breaking down complex sentences and reorganizing the material using a more logical structure, in addition to replacing legal jargon and uncommon words with more familiar language and replacing abstract words (e.g., “plaintiff”) with more concrete terms or specific names (e.g., the plaintiff’s actual name). Other changes include eliminating negatively modified sentences, using the active rather than the passive voice, removing prepositional phrases, and replacing nominalizations (nouns that have been constructed from a verb) with verbs (e.g., change “the thinking of” to “think about”). In the process of applying these psycholinguistic principles and improving comprehension, the legal accuracy of instructions has not been sacrificed.

Jurors typically are given instructions just prior to deliberations. However, several studies have found that delivering instructions twice, once at the beginning of the trial and again after the evidence has been presented, improves comprehension somewhat. In addition, delivering pretrial-instructions gives participants a framework for interpreting the evidence, making them more attentive to due-process issues designed to protect the defendant such as burden of proof. However, comprehension has not been improved on a reliable basis when jurors are only given pretrial instructions (that are not repeated following attorneys’ closing statements).

Traditionally, the judge delivers instructions to jurors orally. However, an alternative delivery approach is to provide written instructions to the jurors that can be brought into the deliberation room. Several studies have shown that comprehension levels are increased when written instructions are provided, and that jurors are better able to apply the law. However, other studies have produced contradictory findings and have not found improvements for comprehension or verdict differences when written instructions are used.

Special verdict forms may be used to ensure that jurors attend to key elements that are conveyed in jury instructions. A special verdict form consists of a series of questions regarding separate issues of fact to which jurors must respond. These forms are used in both civil and criminal trials in the United States and in other countries. Similarly, flow charts (also known as decision trees) indicate the order in which decisions regarding different legal questions should be answered and the appropriate verdict that should be rendered as a result of those decisions. It is possible that instruction comprehension can be improved through the administration of these forms and charts because jurors are required to attend to key legal questions that must be resolved. To date, only a few studies have examined the effectiveness of special verdict forms and flow chart/decision-tree models, and those studies have produced mixed results. Some research has shown that instruction comprehension is improved by these techniques and that jurors believe that special verdict forms are helpful in improving their understanding of instructions and rendering a verdict that they are confident in and satisfied with. However, other research has shown that comprehension is not increased by these techniques and that jurors do not use flow charts when they are provided during deliberations.

When jurors are unsure as to the meaning of instructions, they may attempt to resolve their confusion during deliberations by discussing the matter with each other. If one or more jurors have a very good understanding of the instructions, it may be possible for them to clarify the instructions for others, thus improving the overall comprehension level of the jury. Research has indicated that jurors have some discussion regarding the meaning of instructions in most trials. Unfortunately, jurors are unable to clarify misunderstood points on a regular basis and, as a result, deliberation does not appear to be a successful remedy for comprehension problems. Rather, it has been demonstrated that jurors are as likely to replace an initially correct understanding of instructions with an incorrect one as to correct a misunderstood point of the instructions.

Jurors may also turn to the judge to clarify instructions. Although judicial clarification may be the best possible solution to instruction comprehension problems, judges typically either re-read the problematic instructions or do nothing at all and simply allow jurors to proceed relying on their best memory and understanding of the instructions originally delivered. The lack of judicial responsiveness to jurors’ requests for clarification is based on concerns regarding appeals. It is unlikely that a decision will be reversed on the basis of the instructions provided when the judge restricts his or her comments to the pattern instructions. However, if he or she deviates from the specific wording in the pattern instructions, it can be argued that the language used to clarify the instructions was inappropriate.

The “Plain English” Movement and the Future of Jury Instructions

The primary problem associated with judicial instructions is that they have traditionally been conveyed in a manner that emphasizes legal accuracy, with minimal attention paid to comprehensibility among a nonlegal professional audience. The development of pattern instructions was seen as an improvement to the instruction process, and it did reduce the time judges spent developing instructions for jurors as well as the number of appeals based on instructions while increasing instruction consistency across cases. However, pattern instructions did not serve to remedy comprehension problems.

Recently, states have begun to respond to the recommendations of social scientists by redrafting pattern instructions using a “plain English” approach and applying psycholinguistic principles. For example, in 2003, California approved approximately 800 new civil jury instructions and special verdict forms and revised its criminal jury instructions in 2006. Other states are either considering or in the process of making similar revisions (including Delaware, Iowa, Michigan, Minnesota, Missouri, North Dakota Arizona, Florida, Vermont, and Washington). It is hoped that in the future, continued assessment and revision of instructions accompanied by the application of theoretical perspectives from cognitive and social psychology will continue to improve the jury instruction process, leading to verdicts that are based on a true understanding of the law by jurors.


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