2000, Vol. 6, No. 3, 677-711 1076-8971/00/$5.00 DOI: 10.1037//1076-8971.6.3.677
UNDERSTANDING THE LIMITS OF
LIMITING INSTRUCTIONS
Social Psychological Explanations for the Failures
of Instructions to Disregard Pretrial Publicity
and Other Inadmissible Evidence
Joel D. Lieberman Jamie ArndtUniversity of Nevada, Las Vegas University of Missouri—Columbia Inadmissible information may come in a variety of forms including pretrial publicity and in-court statements made by witnesses or attorneys. A number of remedies have been proposed for controlling the damaging effects of such evidence. When inad-missible information comes in the form of pretrial publicity, judges may issue a continuance or rely on voir dire to remove biased jurors. In addition, it has been argued that deliberations may serve as an effective remedy. Finally, judges may issue an admonition to disregard pretrial publicity or other inadmissible evidence presented in court. Empirical research has demonstrated that such safeguards are relatively ineffective and sometimes produce a backfire effect, resulting in jurors being more likely to rely on inadmissible information after they have been specif-ically instructed to disregard it. Several social psychological theories provide explanations for the failures of admonitions, including belief perseverance, the hindsight bias, reactance theory, and the theory of ironic processes of mental control. Existing inadmissible evidence research and relevant social psychological theories are reviewed. The article concludes with a discussion of theoretically based policy recommendations.
A basic tenet of jury trials is that jurors are supposed to render a verdict based on admissible evidence presented during the course of a trial. Information is admissible when it is relevant to the case at hand and has probative value. Of course, not all testimony that is relevant and informative is admissible. Informa-tion that was illegally obtained, is redundant, misleading or confusing to the jury, or is extremely prejudicial can be ruled inadmissible. Jurors can be exposed to inadmissible information from a variety of sources. This exposure may occur prior to the start of a trial in the form of pretrial publicity (Kramer, Kerr, & Carroll, 1990; Moran & Cutler, 1991). It may also occur during a trial via statements made by attorneys or witnesses regarding a defendant's past criminal behavior (Greene & Dodge, 1995), coerced confessions (Kassin & McNall, 1991; Kassin & Wrightsman, 1980), or other incriminating information (Carretta & Moreland, 1983; Pickel, 1995; Sue, Smith, & Caldwell, 1973; Thompson, Fong, & Rosen-han, 1981). Because jurors should not consider this type of information in their
Editor's Note. Bruce Sales served as the action editor for this article.—BDS
Joel D. Lieberman, Department of Criminal Justice, University of Nevada, Las Vegas; Jamie Arndt, Department of Psychological Sciences, University of Missouri—Columbia.
Correspondence concerning this article should be addressed to Joel D. Lieberman, Department of Criminal Justice, University of Nevada, 4505 Maryland Parkway, Box 455009, Las Vegas, Nevada 89154-5009. Electronic mail may be sent to [email protected].
decision-making process, the judge must intervene and attempt to remove this prejudicial evidence procedurally, often by issuing an instruction to disregard it. However, a large body of research indicates that jurors have great difficulty ignoring information once they have become aware of it. Several social psycho-logical theories offer potential explanations as to why jurors are unable to ignore inadmissible information and why they sometimes pay greater attention to this evidence when an admonition is given than when a judge says nothing at all.
This article reviews the relevant social science research pertaining to the biasing effects of pre-trial publicity and inadmissible evidence, and seeks to understand why these effects occur and what steps might be taken to attenuate them. We begin by examining the consequences of exposure to pretrial publicity. This section is accompanied by a critique of solutions that courts have used to reduce the impact of such information. The damaging effects of exposure to inadmissible evidence presented in court are then reviewed. We examine factors that contribute to jurors' inability to ignore such information despite being specifically instructed to do so. A number of social psychological theories that offer potential explanations for this phenomenon are presented. We conclude with a comparison of the different explanations and an articulation of theoretically based policy recommendations for reducing inadmissible evidence effects.
The Problem of Pretrial Publicity
The first type of prejudicial inadmissible information that jurors may be exposed to is media reports of a crime and the subsequent upcoming trial. The proliferation of cable news channels and tabloid television shows has created media circuses surrounding trials for such recent defendants as William Kennedy Smith, O.J. Simpson, the officers involved in the Rodney King beatings, the Menendez brothers, and Timothy McVeigh, just to name a few. In addition, the growth of the Internet has created another medium through which publicity can be disseminated. However, concerns about the impact of pretrial publicity are cer-tainly not limited to recent events. As Carroll et al. (1986) has noted, there has been a long-standing controversy between the right to a free press protected by the First Amendment and the Sixth Amendment's guarantees of a "speedy and public trial, by an impartial jury of the State and district wherein the crime shall have been committed" (U.S. Constitution).
Perhaps the earliest example of the conflict between a free press and a fair trial was the 1807 treason trial of Aaron Burr. Burr argued that a series of inflamma-tory newspaper articles had so biased community opinion against him that it was impossible to get a fair trial. Chief Justice Marshall responded by ruling that there was no requirement in the law that a jury be free of "any prepossessions whatever respecting the guilt or innocence of the accused." However, jurors could be disqualified if they "have deliberately formed and delivered an opinion on the guilt of the prisoner as not being in a state of mind to fairly weigh the testimony"
(United States v. Burr, 1807). The sentiment that it is impossible to find a jury that
has not been exposed to any pretrial publicity, but that such exposure does not automatically imply that jurors will be unable to fairly evaluate trial testimony, has remained throughout the history of the United States legal system.
other defendants in highly publicized trials) are valid. Once jurors have been exposed to pretrial publicity, it becomes quite difficult to eliminate its biasing effects (Steblay, Besirevic, Fulero, & Jimenez-Lorente, 1999). Survey research has indicated that individuals who live near an area where a crime was committed frequently develop a proprosecution bias (Moran & Cutler, 1991), a bias likely due to greater pretrial exposure to prejudicial information (Nietzel & Dillehay, 1983). Similarly, individuals exposed to actual media reports of crime also develop a proprosecution orientation (Constant! & King, 1980; Freedman & Burke, 1996; Moran & Cutler, 1991; Simon & Eimermann, 1971). For example, Moran and Cutler (1991) examined public perceptions of defendants in two highly publicized trials. The first trial involved the indictment of defendants in a marijuana distribution case in rural southern Illinois. The second trial was a highly publicized murder of a police officer in Miami. Moran and Cutler demonstrated that in both trials, greater pretrial knowledge about case details was positively associated with perceived culpability of defendants. However, there was no relationship between awareness of case details and the likelihood of a respondent stating that they could be fair and impartial. In addition, many respondents who claimed they could be impartial admitted that they would be unable to set aside case-relevant news stories to which they had been exposed. This finding indicates that although potential jurors are cognizant that they have been exposed to damaging pretrial publicity, they still claim impartiality when in fact they have already developed a prejudicial opinion of the defendant.
Experimental research has also demonstrated a damaging effect for pretrial publicity. Padawer-Singer and Barton (1975) presented mock jurors with publicity surrounding a murder case before exposing them to an audiotaped trial of the same case. Newspaper reports either indicated that the suspect had retracted a confession and had a criminal background or did not mention the confession and background of the suspect. As expected, participants exposed to the confession and background information were more likely to convict the defendant.
Several researchers have made a distinction between factual and emotionally oriented pretrial publicity (Kramer et al., 1990; Ogloff & Vidmar, 1994; Wilson & Bornstein, 1998), and it appears that both types of publicity may be damaging to defendants. Factual publicity refers to information that is incriminating to the defendant (such as prior conviction information or other incriminating evidence). Emotional publicity refers to information that arouses negative feelings toward the defendant but is not incriminating, per se. For example, hearing that a murder was carried out in a particularly violent and brutal manner would likely produce emotional arousal in an audience but is not an indicator of the probability of guilt. Kramer et al. (1990) exposed mock jurors to various types of pretrial publicity in the form of simulated newspaper articles regarding a bank robbery before presenting participants with a videotaped trial for that robbery. The newspaper articles were designed to reflect the different kinds of pretrial publicity informa-tion that jurors might receive. Participants were presented with either high or low factually oriented and either high or low emotionally oriented publicity. Both types of pretrial publicity led to greater convictions, and judicial instructions to ignore the information were completely ineffective. A continuance of several days separating exposure to the publicity and the viewing of the trial was an effective
remedy for factual publicity. However, the continuance was ineffective at reduc-ing the effects of emotional publicity.
Wilson and Bornstein (1998) obtained similar findings regarding the effects of emotional and factual pretrial publicity. The authors found that there was an overall biasing effect of pretrial publicity compared with a control condition. However, no significant differences emerged between either factual or emotion-ally based publicity. Interestingly, they did not obtain a difference between mediums used to present the publicity. Participants were exposed to publicity in either a videotaped or written format. Both formats produced similar levels of publicity-based biases against the defendant.1
The content of pretrial publicity may also affect verdicts. In the Model Rules
for Professional Conduct, the American Bar Association (ABA; 1983) outlined
categories of information considered to be highly prejudicial to a defendant that should not be publicly disseminated: opinions regarding the guilt or innocence of the accused; comments regarding the strength of the evidence; prior record information; details about the character or reputation of the accused; pretrial confessions, statements, or refusal to make a statement; refusal to submit to relevant tests or exams, or test or exam performance; or pleas of guilt to the offense or to a lesser offense. A content analysis by Imrich, Mullin, and Linz (1995) found that 27% of suspects identified in newspaper crime stories were described in reports that contained negative information that violated the ABA standards. Among the most common ABA categories that were publicly revealed were negative statements about the suspect, prior arrest information, opinions of guilt, confessions, and prior conviction information. Law enforcement officers and prosecutors were the most frequent sources of prejudicial information to the newspapers.
Early experimental research on pretrial publicity demonstrated a cumulative effect for categories of pretrial publicity. Tans and Chaffee (1966) presented participants with pretrial newspaper crime reports that varied in terms of crime seriousness, confessions or denials made by the suspect, information regarding whether the suspect was held in custody or released, and either favorable or unfavorable statements made by the district attorney toward the defendant. Par-ticipants were more likely to judge the defendant guilty when all the unfavorable
'However, the nonsignificant findings in Wilson and Bernstein's (1998) study contrast with previous work conducted by Ogloff and Vidmar (1994). Using an actual case, Ogloff and Vidmar also varied the medium used to present publicity. The pretrial publicity was composed of actual newspaper and television reports of an emotionally charged sexual molestation case involving priests at an orphanage. Participants viewed print articles, video, or both articles and video. Their results indicated that video publicity created greater bias and produced a significant increase in perceptions of guilt compared with written publicity. The greatest perceptions of guilt occurred when individuals were exposed to both written articles and video. Wilson and Bornstein argue the contradictory findings may be due to Ogloff and Vidmar confounding medium with trial informa-tion. Because Ogloff and Vidmar used actual newspaper and television excerpts, it was impossible to equate the information contained in the publicity, despite their attempts to do so. Wilson and Bornstein simulated the publicity presented to their participants. Consequently, it was possible for them to have identical texts in the video and written formats. In addition, participants in the Ogloff and Vidmar study were not exposed to a trial, whereas Wilson and Bornsteins' participants were.
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information was presented Overall, the results indicated that a police report of a confession was the most damaging category of information.
More recent work has also demonstrated that different types of pretrial publicity appear to have differential effects on juror verdicts. In a laboratory experiment, Otto, Penrod, and Dexler (1994) manipulated the type of publicity jurors were exposed to (either character information, weak or strong inadmissible statements regarding beliefs in guilt, comments about the defendant being of low status, and prior record information) before presenting a videotaped trial to participants. Otto et al. (1994) reported that comments about the character of a defendant (the most frequent category of reported information according to Imrich et al., 1995) and both weak and strong inadmissible statements have a direct effect on pretrial judgments of guilt. Pretrial judgments in turn have an effect on perceptions of the defendant, beliefs in the strength of the case presented by the prosecution, and importantly, final verdicts. Trial evidence reduced the damaging effects of pretrial publicity but did not eliminate it entirely. Finally, prior record information indirectly influenced final verdicts by leading participants to believe that the defendant was a "typical criminal."
One way to understand the effects that viewing a defendant as a "typical criminal" engenders is to consider the social psychological construct of schemas. Schemas are mental representations of categories of objects or events in the world (Brewer & Crano, 1994). The activation of trial-relevant schemas appears to have a powerful effect on verdict choice because of jurors' reliance on "commonsense justice" (Finkel, 1995). Finkel and Handel (1988, 1989) concluded that verdict decisions regarding insanity are affected by jurors' preexisting schemas. Jurors appear to have elaborate conceptions of insanity (far beyond legal definitions) and are likely to render verdicts consistent with those schemas rather than relying on legal standards provided by the judge (for a complete review, see Finkel, 2000). Further, Smith (1991) has demonstrated that jurors have preexisting mental representations of the elements of different crimes (such as burglary and robbery) that often do not include the correct legal definitions of those crime categories. These preexisting prototypes are not discarded when conflicting judicial instruc-tions are presented, even when individuals are instructed to do so. Consequently, this research indicates that the development and application of schemas regarding typical crimes and typical criminals is extremely difficult to overcome and suggests that pretrial publicity regarding a particular defendant is likely to lead to the application of those schemas. For an excellent review of the application of commonsense justice to pretrial publicity effects, see Studebaker and Penrod (1997).
A recent meta-analytic review by Steblay et al. (1999) provided additional support for the results of the aforementioned individual pretrial publicity studies. Steblay et al. examined 44 empirical pretrial publicity investigations involving 5,755 participants. The results indicated that there clearly was an overall damag-ing effect of negative pretrial publicity. Greater effects sizes were obtained in studies with higher external validity such as when potential juror pool participants were used rather than undergraduates, when real pretrial publicity was used as opposed to simulated publicity, and with greater length of time between pretrial publicity exposure and judgment. In addition, greater effect sizes were also obtained when participants were asked to indicate verdict preferences prior to trial
exposure, when there were multiple items of negative information in the publicity, and in crimes of murder, sexual abuse, or drugs.
Proposed Solutions to Pretrial Publicity Problems
Of course, courts do recognize that pretrial publicity may be damaging to a defendant and do take measures to reduce the impact of it. These measures come in a variety of forms, including attempting to identify and eliminate biased jurors during voir dire, providing a continuance to delay the start of the trial, hoping jury members will censure any individual jurors who bring up pretrial publicity during deliberations, and admonishing jurors to ignore publicity they have been exposed to. However, there are limitations with each of these potential solutions.
Voir Dire
The first step in removing the contaminating effects of pretrial publicity is to use the voir dire process to exclude jurors who have been influenced by it to such an extent that they can no longer be impartial triers of fact. However, existing research indicates that attorneys are generally unable to successfully use voir dire to achieve this goal. Dexter, Cutler, and Moran (1992) found that after exposure to pretrial publicity, mock jurors were more punitive toward defendants, despite an extended voir dire process focused on educating jurors, making them account-able, and directly asking them about their influence.
Sue, Smith, and Pedrozza (1975) found that even when jurors claim to be unbiased, their verdicts are still affected by pretrial publicity. Participants were shown pretrial publicity that was either neutral or damaging to a defendant and were asked if they would be able to render an unbiased and fair verdict. After reading a summary of a trial, participants indicated their verdicts. Not surpris-ingly, participants who said they would be unable to render a fair verdict were more likely to convict the defendant than those jurors who said they could be impartial. However, participants who claimed that they were not influenced by the publicity were actually more likely to convict the defendant if they had been presented with negative publicity as opposed to neutral publicity. These results are consistent with those obtained by several other research teams (Kerr, Kramer, Carroll, & Alfini, 1991; Thompson et al., 1981).
Further, a study by Freedman, Martin, and Mota (1998) found that the damaging effect of publicity may be increased (rather than decreased) by ques-tioning jurors about their exposure to pretrial crime details. Freedman et al. (1998) found no effects of negative pretrial publicity on mock juror verdicts unless participants were first asked to indicate their pretrial opinions of guilt. The authors interpreted this as participants becoming more committed to their positions after rendering pretrial opinions of guilt. Similarly, the Steblay et al. (1999) meta-analysis indicated a greater pretrial publicity effect in studies where participants expressed pretrial judgments.
It should be noted that Padawer-Singer, Singer, and Singer (1974) reported that although pretrial publicity produced an increase in guilty verdicts in their own study of pretrial publicity, voir dire was successful at controlling these prejudicial effects. Unfortunately, interpretation of the contradictory findings obtained by
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Padawer-Singer et al. (1974) is difficult because the authors failed to report any statistical significance tests.
Voir dire ultimately serves as a self-report measure of attitudes and experi-ences, and like all self-report measures, it is susceptible to intentional or unin-tentional deception. That is, jurors may be unwilling or unable to admit their exposure to pretrial publicity and the effect it has had on them. Additionally, in light of the abundance of studies that indicate that jurors who claim to be unbiased are still influenced by pretrial publicity, it seems unlikely that attorneys will be able to accurately predict and select jurors who will act in an unbiased manner. Finally, in an actual highly publicized trial, the limitations of voir dire as an effective remedy are likely to be intensified. Given the potential for appearances on talk shows, lectures, book deals, and the attention and financial gain that may ensue, some jurors may be especially motivated to deny that they have been influenced by pretrial publicity.
Continuance
Because it is difficult, if not impossible, to use voir dire to successfully eliminate biased jurors, courts may rely on other methods of reducing the impact of pretrial publicity. One available option is to delay the start of the trial by issuing a continuance. The goal behind a continuance is to delay the trial long enough for publicity to subside and the effects to decay. Although minimal empirical research exists on the effectiveness of continuances at reducing the impact of pretrial publicity, a few studies have addressed this issue. Davis (1986) found that a 7-day delay (compared with no delay) tended to reduce the impact of factually oriented prejudicial publicity but not neutral publicity on postdeliberation verdicts. How-ever, no instructions to disregard pretrial publicity were provided, and overall there was no difference in conviction rates between jurors exposed to neutral and negative pretrial publicity.
In addition, Kramer et al. (1990) investigated the effects of a continuance at reducing both factual and emotional pretrial publicity effects. Recall that both types of pretrial publicity led to greater convictions, and judicial instructions to ignore the information were ineffective. Participants were exposed to the publicity either immediately prior to viewing a trial or 12 days prior to the trial. The 12-day continuance separating exposure to the publicity and the viewing of the trial was an effective remedy for factual publicity but not for emotional publicity. The authors speculated that the differential effects of publicity type on the success of the continuance may be due to emotionally oriented information being potentially more memorable than factually based publicity. Such an explanation is consistent with a wide body of social cognition research showing that emotional information is strongly connected to attention and memory processes (see e.g., Ellis & Moore,
1999, for a recent review).
An important consideration with the Kramer et al. (1990) study, however, is that the continuance was only 12 days, which is considerably shorter than what would occur in an actual trial. A longer continuance may have produced a significant reduction in the effects of emotional publicity. However, in an actual case, jurors would be exposed to a much greater amount of pretrial publicity than is possible to achieve in a laboratory experiment. In addition, the results of the
meta-analysis conducted by Steblay et al. (1999) described above indicated that the effects of negative pretrial publicity were greater in studies that used longer delays (greater than 7 days) between exposure to pretrial publicity and juror judgment. Consequently, the effectiveness of continuances is still far from
conclusive.
Deliberations
Deliberations have been suggested as another means of reducing the biasing effects of inadmissible information. Although jurors may be tempted to privately consider inadmissible evidence, it is more difficult to publicly do so because such considerations are not justifiable to other jurors (Kerwin & Shaffer, 1994). Mixed results have been obtained in studies investigating the effectiveness of deliberation.
Kramer et al. (1990) obtained contradictory findings in an examination of pretrial publicity effects. Following exposure to pretrial publicity and trial evi-dence, the deliberations of mock jurors were videotaped and content analyzed. Juror comments about the publicity that they had been exposed to were relatively rare and quite brief when they occurred. Further, when inadmissible publicity was mentioned, jurors almost always reminded each other not to consider it. However, despite the fact that jurors' comments about publicity were minimal, the delib-erations were not a successful remedy for publicity effects. In fact, delibdelib-erations served to increase the effects of emotional publicity.
On the basis of extant empirical research, it does not appear that deliberations are an effective safeguard against the effects of pretrial publicity. To some extent this result is not surprising. Damaging inadmissible evidence may be congruent with jurors' schemas for criminals. The application of such schemas may have a large impact on interpretation of trial evidence. Because deliberations occur after the presentation of trial evidence, they may be too late to effectively reduce the impact of inadmissible evidence. In addition, studies on group polarization (Moscovici & Zavalloni, 1969) suggest that communal discussion will often intensify initial opinions rather than attenuate them.
Admonitions
When considerable pretrial publicity exists, judges may respond by caution-ing jurors to ignore the information. Early research indicated that admonitions were successful in overcoming pretrial publicity effects (Kline & Jess, 1966; Simon, 1966) but were limited by several methodological complications. For example, Kline and Jess (1966) reported judicial instructions effectively removed the biasing effects of pretrial publicity in three out of four mock juries. However, confidence in their findings is reduced by their use of an extremely small sample (only four mock juries were exposed to pretrial publicity).
In addition, Simon (1966) found admonitions to be an effective safeguard for pretrial publicity effects. In that study, mock jurors were exposed to either conservative or sensational pretrial publicity. Conservative publicity was modeled after reports in newspapers such as The New York Times or Washington Post. Sensational news reports, on the other hand, were designed to simulate tabloid newspaper stories. Consequently, sensational stories were designed to have a
greater emotional impact on the readers. Simon reported that more pretrial guilty verdicts were produced after exposure to sensational publicity than conservative publicity. However, an admonition delivered early in the trial eliminated the differential publicity effects. Unfortunately, it is difficult to interpret the overall effectiveness of the admonitions because of an absence of a control group in which jurors were not exposed to an admonition. Further, potential demand characteristics were created because the jurors were told ahead of time that the study was examining "the problem of pretrial publicity."
More recent research has indicated that there is cause for concern about the prejudicial impact of pretrial publicity. For example, Sue, Smith, and Gilbert (1974) gave participants newspaper accounts of details about a case before presenting a trial summary and judicial admonitions. The articles described either damaging or irrelevant pretrial publicity. Sue et al. found that pretrial publicity increased perceptions of the strength of the prosecution's case and the number of guilty verdicts. Judicial instructions to ignore pretrial publicity were ineffective at reducing the biasing effects of the publicity.
Other researchers have obtained similar results. As previously mentioned, Kramer et al. (1990) exposed participants to either factual or emotionally oriented pretrial publicity before administering jury instructions that either admonished jurors to disregard the publicity or did not mention it. The instruction was ineffective at reducing the effects of both types of publicity.
Fein, McCloskey, and Tomlinson (1997) also found that judicial admonitions were ineffective at reducing the effects of pretrial publicity and hearsay testimony. However, jurors were less likely to be influenced by inadmissible evidence if suspicion had been cast about the motivation of the source of that inadmissible information. This study is described in greater detail later in this article.
In-Court Inadmissible Evidence Studies
Admonition ineffectiveness is not limited to pretrial publicity but also occurs with other types of inadmissible evidence. When inadmissible evidence is pre-sented in court, the typical judicial response is to attempt to remove the prejudicial influence of the evidence by issuing a limiting instruction to disregard it. Limiting instructions can be used for a number of purposes. First, a judge may instruct jurors that certain evidence is completely inadmissible, such as illegally obtained evidence that is incriminating to the defendant. This type of evidence is not allowed for any purpose. If it is somehow introduced during a trial, the judge instructs jurors to disregard it.
Second, a judge may instruct jurors that they may use evidence for certain purposes but not for others. For example, if a defendant testifies during a trial, the judge may allow evidence to be admitted that the defendant has a prior record of convictions. Jurors are instructed to limit their use of this evidence to determine the credibility of the defendant's testimony and not to use that information to infer that the defendant has committed an act, has negative traits, or has a criminal disposition. Similarly, a judge may allow prior conviction information to show that a defendant had a motive, an opportunity, specific knowledge, or has used a common pattern, but again jurors are instructed not to infer negative traits about the defendant (Cox & Tanford, 1989). When limited-use evidence is used for
unintended purposes, it is considered prejudicial to the defendant. With few exceptions, empirical research has repeatedly demonstrated that both types of limiting instructions are unsuccessful at controlling jurors' cognitive processes.
Many of the limiting instruction studies have focused on prior conviction information. For the most part, these studies have indicated that jurors are influenced by such information. For example, Doob and Kirshenbaum (1973) presented participants with a hypothetical burglary case and informed half the participants that the defendant had a prior record. Participants were more likely to rate the defendant as guilty when they were exposed to prior criminal record information than when no record information was given. Although participants were also presented with judicial instructions informing them that prior record information should be used to determine credibility, rather than as an indicator of guilt, the instructions did not serve to significantly reduce average ratings of guilt. One possible limitation of this study is that the mock jurors did not deliberate. Deliberation might overcome this inappropriate use of criminal record because jurors might be less likely to publicly consider such information.
In a follow-up study, Hans and Doob (1976) ruled out this possibility. Mock jurors were again given a written summary of a hypothetical burglary case before being allowed to deliberate. Consistent with Doob and Kiershenbaum's (1973) findings, groups that received prior conviction evidence accompanied by limiting instructions were more likely to convict (40%) than groups who did not receive prior conviction evidence (0%). The presence of inadmissible evidence also affected the content of the deliberations. Although groups who read the prior conviction evidence made more references to reasonable doubt, they also made significantly more positive statements about the prosecution's evidence and more negative statements about the defendant. Hans and Doob (1976) concluded that jurors use evidence regarding convictions as an indicator of guilt rather than to determine the credibility of statements made by the defendant, despite judicial instructions to the contrary.
Wissler and Saks (1985) obtained similar results in a study where participants were told that the defendant had previously been convicted of either a similar crime, a dissimilar crime of perjury, or were given no information about a prior record. Participants presented with prior record information were instructed to use it only as a determinant of the credibility of the statements made by the defendant and not as an indication that the defendant had a criminal disposition. Interest-ingly, the defendant's credibility ratings were not affected by prior conviction information. Jurors who read about a defendant previously convicted of perjury did not view the defendant as less credible than jurors who read about the other defendants, including a defendant with no prior convictions. However, verdicts were affected by type of prior offense. Participants returned significantly more guilty verdicts for defendants with similar convictions (75%) than defendants with dissimilar convictions (52.5%), perjury convictions (60%), or no convictions (42.5%).
Factors Affecting the Success of Admonitions
A variety of factors appear to affect the success of limiting instructions. First, as just mentioned in the Wissler and Saks (1985) study, jurors appear to be
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influenced by the similarity of prior conviction evidence to the current case. Similarly, Sealy and Cornish (1973) found that British jurors were able to correctly follow instructions and ignore inadmissible evidence about prior con-victions when the prior concon-victions were for dissimilar offenses.
There is also support for the possibility that admonition effectiveness is affected by evidence strength. Sue et al. (1973) presented either strong or weak evidence against a defendant accused of murder. In weak-evidence conditions, a greater number of guilty verdicts were rendered when an item of evidence was presented and ruled inadmissible than when it was not presented at all. However, when a strong case against a defendant existed, jurors followed the judge's instructions to ignore inadmissible evidence. Consequently, the biasing effect of inadmissible evidence may be greatest when jurors are faced with weak or equivocal evidence. Similarly, Rind, Jaeger, and Strohmetz (1995) found that inadmissible evidence had a greater effect in less serious crimes (vandalism). However, for the more serious crimes of homicide and arson, jurors were not influenced by inadmissible evidence. These results were consistent with those obtained by Sealy and Cornish (1973). In that study, inadmissible evidence had an effect on mock jurors in a minor theft case but not in a serious rape case. This finding may indicate that jurors have a greater concern for due process when a defendant is charged with a serious crime or when there is strong evidence against him or her. However, it is important to remember that these studies were jury simulations, and no actual defendants were on trial. In real trials, when there is a chance of returning a potentially dangerous criminal to the community, jurors may be more inclined to consider all information that has probative value (regardless of its admissibility) than is indicated by experimental research.
Kerwin and Shaffer (1994) reported that the process of deliberations may moderate the impact of inadmissible evidence. They note that several studies that have failed to obtain inadmissible evidence effects have used group verdicts (Carretta & Moreland, 1983; Kline & Jess, 1966; Sealy & Cornish, 1973). Consequently, Kerwin and Shaffer predicted that when incriminating inadmissible evidence is presented and individual juror verdicts are compared with aggregate jury verdicts, greater convictions should be expected in the individual verdicts. In a mock juror study, they obtained results consistent with this hypothesis. How-ever, in a study on the effectiveness of instructions to disregard inadmissible evidence, Hans and Doob (1976) found that limiting instructions were not effective even when jurors were allowed to deliberate. These results are consistent with Kramer et al. (1990).
Extra-legal biases may also determine whether inadmissible evidence is considered. In a laboratory experiment, Johnson, Whitestone, Jackson, and Gatto (1995) found the effects of inadmissible evidence appear to be moderated by the race of the defendant. Caucasian participants were more likely to consider incriminating inadmissible evidence when the defendant was Black than when the defendant was White.
Interestingly, the effects of prior conviction information do not carry over to prior acquittal information. Greene and Dodge (1995) found no difference in the percentage of guilty verdicts between jurors who were given prior acquittal record information and no prior record information. However, consistent with previous research (Doob & Kirshenbaum, 1973; Hans & Doob, 1976; Wissler & Saks,
1985), jurors were more likely to convict when they were given evidence of prior convictions than when they were given no record information despite judicial instructions warning against using this information. Further, although prior con-viction evidence led participants to perceive the defendant as less credible and more dangerous, prior acquittal evidence had no effect.
Kassin and Sommers (1997) provided further evidence that jurors selectively use inadmissible evidence. They presented mock jurors with a murder trial and manipulated the presentation of a key piece of incriminating evidence. In a control condition, only circumstantial and ambiguous evidence was presented. In exper-imental conditions, an additional piece of evidence was presented. The evidence was an audiotaped telephone conversation between the defendant and a friend in which the defendant confessed to the killings. After the presentation of the tape, a defense attorney objected. In an admissible-evidence condition, the judge overruled the objection and allowed it as a proper form of evidence. In other conditions, the judge sustained the objection and ruled the evidence inadmissible because it was either illegally obtained or barely audible, making it difficult to determine what was said. Kassin and Sommers found that the admissible confes-sion produced a significant increase in guilty verdicts compared with the control condition. However, participants in the two inadmissible conditions behaved very differently. When participants were instructed to ignore the evidence because it had been illegally obtained, they tended to disregard the admonition and rendered verdicts similar to those of participants in the admissible-evidence condition. But, when participants were instructed to disregard the evidence because of the poor quality of the tape, they did so, behaving like control participants who were not exposed to the incriminating evidence. Kassin and Sommers interpreted this as jurors being influenced by the causal basis of the judge's ruling rather than the ruling itself. If mock jurors are given a logical reason for the judge's decisions that they believe is legitimate, then there is evidence that they are able to obey the admonitions.
Not only are mock jurors hesitant to use inadmissible information that they feel is unreliable, laboratory studies have also indicated that jurors are less influenced by inadmissible information when their suspicion has been aroused. Fein et al. (1997) reported that jurors were less likely to rely on pretrial publicity or hearsay testimony in their decision making if suspicion had been cast about the motivation of the source of that inadmissible testimony. For example, Fein et al. (1997) aroused suspicion by presenting an article that quoted the defense attorney in the case claiming that the "media manipulates information to sell papers, and knowingly ignores facts which would point toward a defendant's innocence" (p. 1219). However, as noted above, both types of inadmissible information were prejudicial to the defendant if suspicion was not aroused and the inadmissible evidence was simply accompanied by a judicial admonition.
Surprisingly, a study by Thompson et al. (1981) found that inadmissible evidence was only influential on jurors when it was favorable to the defendant. The number of guilty verdicts rendered was not significantly increased when proprosecution inadmissible evidence was presented (compared with a control condition where inadmissible evidence was not presented). This finding contra-dicts much of the existing inadmissible-evidence research. The surprising failure of proprosecution evidence to have an effect on verdicts may be due to the nature
of the inadmissible evidence presented. The evidence consisted of inadmissible testimony that either supported (prodefense) or contradicted (proprosecution) a defendant's alibi. However, all participants had already been exposed to other highly incriminating evidence about the defendant and may have already devel-oped a prosecution bias. Thus, although acceptance of the alibi should reduce the number of guilty verdicts, rejection of it should not necessarily increase the number of guilty verdicts.
The effects of admonitions to disregard evidence are not limited to percep-tions of the defendant but carry over to perceppercep-tions of victims. Johnson (1994) investigated the impact of admonitions to disregard victim sexual history infor-mation and rape type (stranger vs. acquaintance rape) on perceptions of rape victims. He found that admonitions were effective at reducing perceptions of victim enjoyment of the assault. However, this effect was qualified by an inter-action between information admissibility and rape type. When prior sexual history information was ruled admissible, perceptions of victim enjoyment did not vary as a function of rape type. However, when such information was ruled inadmis-sible, greater perceptions of victim enjoyment were reduced in the stranger-rape condition but not in the acquaintance-rape condition. These results indicate that admonitions can be effective, depending on the nature of the crime. Participants may have felt that sexual history information was not relevant in a stranger-rape case. The belief that such information did not have a probative value may have made it easier to disregard. However, participants may have felt that prior sexual history information was informative in an acquaintance rape scenario, making it difficult to ignore and contributing to a derogation of the victim as someone who did not mind being raped.
Backfire Effect
Perhaps the most interesting aspect of the research on admonitions to disre-gard evidence has been the demonstration of a backfire effect (Cox & Tanford, 1989). The backfire effect occurs when jurors pay greater attention to information after it has been ruled inadmissible than if the judge had said nothing at all about the evidence and allowed jurors to consider it.
Breeder (1959) found that participants awarded higher damages to a plaintiff after being instructed by a judge to disregard a statement that a defendant was covered by insurance than when given no instructions to that effect. When no mention of insurance was made, the average amount of damages awarded was $33,000. In a second condition, where jurors were informed that the defendant had insurance (but no admonitions were given) the damages rose to $37,000. Finally, in an admonition condition, jurors were instructed to disregard what they had heard regarding the defendant's insurance. Rather than the mean award dropping to the baseline of $33,000, awards were highest at $46,000.
Similar findings were obtained by Cox and Tanford (1989, Exp. 2). They presented mock jurors with a videotape reenactment of a farm accident civil negligence trial. During the trial, limited use or inadmissible evidence (damaging to the defendant) was presented. The limited-use evidence consisted of informa-tion about similar acts that had caused severe injury where the defendant had been found liable or testimony from a witness who described the defendant as being
dishonest and unsafe in the design of products. When the limited-use evidence was not accompanied by an admonition, it did not have an effect on juror judgments. However, mock-juror judgments were significantly more punitive when the judge issued an admonition to disregard the limited-use evidence. The damaging effects of limiting instructions were not limited to verdict decisions but also carried over to negligence ratings and character trait ratings (such as credi-bility). Interesting, curative instructions were effective for inadmissible evidence (such as whether the defendant had liability insurance or had offered to settle the case), but inadmissible evidence did increase liability judgments when presented without admonitions (similar effects for inadmissible evidence were also obtained in a prior study, Cox & Tanford, 1989, Exp. 1). Cox and Tanford explained this discrepancy by arguing that limited-use evidence produces character inferences and attributions based on disposition factors, whereas inadmissible evidence (at least the evidence presented in their study) did not lead to trait attributions. Thus, it may be easier to disregard a discrete element of evidence than to ignore a complete character impression based on inappropriate evidence. However, this theory would imply that jurors may still consider inadmissible evidence if such evidence would produce character attributions.
The occurrence of a backfire effect may, in part, depend on the type of inadmissible evidence that is presented to jurors. As previously noted, Kramer et al. (1990) presented participants with either factual or emotional pretrial publicity prior to exposing them to a videotaped trial. Half the participants were given instructions to ignore the publicity, and half were not given judicial admonitions. The defendant was rated significantly more negatively when limiting instructions accompanied factual pretrial publicity than when the instructions were not in-cluded. Consequently, a backfire effect occurred for factual but not emotional pretrial publicity. It is important to recognize, however, that this effect emerged on a measure of impressions of the defendant but did not carry over to verdict preference. As we discuss later, limiting instructions tend to be less effective for emotional information when dealing with verdict preference.
Pickel (1995) compared the effectiveness of judicial admonitions accompa-nied by explanations for the legal basis behind the ruling in a series of studies focusing on two different types of inadmissible evidence—prior-conviction evi-dence and hearsay evievi-dence. Hearsay is generally not admissible because it refers to testimony regarding out-of-court statements made by a third party who does not testify. Hence, it is not possible to cross-examine such out-of-court statements. When hearsay evidence is introduced, judges may instruct jurors to either disre-gard it entirely or to consider it for some limited purpose. Pickel found that jurors did not ignore inadmissible prior-conviction evidence when it was accompanied by a judicial explanation about the basis behind the ruling, and instead a backfire effect occurred. However, admonitions accompanied by explanations were effec-tive at controlling the backfire effect for hearsay evidence. According to Pickel, this discrepancy may reflect jurors' preconceived ideas regarding what type of evidence they should and should not consider. For example, participants felt it was not as fair to consider hearsay than several other types of inadmissible evidence such as illegally obtained evidence, prior-conviction evidence, and information that a defendant was covered by insurance or attempted to settle the case. Consequently, jurors may not only have schemas for crimes and criminals
but also for what should be considered admissible evidence. This possibility is supported by several other studies that have shown that hearsay evidence has a minimal impact and can be reduced by both limited-use instructions and instruc-tions to completely disregard evidence (Landsman & Rakos, 1991; Miene, Park, & Borgida, 1992; Paglia & Schuller, 1998; Rakos & Landsman, 1991; but see Schuller, 1995).
Thus, it appears that admonitions to disregard evidence may not only be ineffective in many situations but may serve to focus jurors' attention on inad-missible evidence and increase their reliance on it in their decision making. However, the backfire effect may not occur when jurors consider the information unreliable.2
Theoretical Explanations for Limiting Instruction Ineffectiveness On the basis of a large extant body of research, it appears that jurors do have difficulty ignoring inadmissible and limited-use evidence. These effects appear to occur for pretrial publicity or statements made in court. A number of psycholog-ical explanations have been suggested to explain the mechanisms that may foster jurors' reliance on evidence they have been specifically ordered to disregard. Belief Perseverance
Research in the area of belief perseverance has demonstrated that once individuals form a belief, the belief becomes highly resistant to change and influences how they perceive and construct future information. For example, Anderson, Lepper, and Ross (1980) presented participants with descriptions of firefighters that portrayed either a risk-taking person as a successful firefighter and a cautious person as unsuccessful, or a cautious firefighter as successful and a risk-taking person as unsuccessful. Participants were asked whether individuals who take risks were good or bad firefighters and were asked to write an essay supporting their beliefs. Participants who read descriptions of the successful risk-taking fire person indicated that risks were a good quality in firefighters, whereas participants who had been presented with successful cautious firefighters believed risk-taking to be a bad quality. When individuals were presented with information that contradicted their beliefs, they discredited the new information rather than altering their views. Their beliefs were enduring and resistant to change, regardless of the information they had been initially presented with. Although, belief perseverance is extremely powerful, it can be overcome by motivating participants to explain why beliefs opposite their own may be true (Anderson, 1982; Anderson & Sechler, 1986), for example, by having people who
2It should be noted that Freedman et al. (1998, Study 1) reported the opposite of a backfire
effect for admonitions. Although they found no effects for negative pretrial publicity compared with neutral publicity, admonitions produced a prodefendant bias. Following exposure to publicity, participants presented with admonitions were less likely to find a defendant guilty and rated him as more honest and likeable. Freedman et al. described this as a leaning over backwards effect. However, it is difficult to assess overall effectiveness of the admonitions because there were no significant effects of pretrial publicity to reduce.
believe that risky firefighters are successful write essays explaining the benefits of being a cautious fire person.
When individuals hear pretrial publicity, they may form initial beliefs about a defendant in a case. According to belief perseverance, these cognitions should influence later interpretation of trial evidence. In addition, when participants are presented with damaging information about a defendant during a trial, beliefs formed by such information should have a powerful effect on jurors and should be resistant to change. Hence, when a judge issues an admonition to jurors to disregard the damaging information, their initial beliefs should persist.
However, even though jurors may be inclined to rely on their initial beliefs, and those beliefs may influence interpretation of trial evidence, belief persever-ance cannot provide a complete explanation for the failure of limiting instructions. Although initial beliefs should be resistant to contradictory information, which fits with evidence showing the basic failure of limiting instructions, it does not explain why jurors are more likely to rely on information when it is ruled inadmissible. In short, belief perseverance does not account for the backfire effect. The research by Kassin and Sommers (1997) described above casts further doubt on belief perseverance as an adequate explanation. In their study, juror verdicts were measured repeatedly throughout the presentation of evidence. Following the presentation of incriminating information about the defendant (an audiotaped telephone conversation where the defendant confessed to the murder he was charged with to a friend), there was a shift in verdicts with an increase in opinions of guilt. However, verdict preferences shifted back as soon as the judge instructed the jury that such evidence could not be considered because the audiotape was barely audible and it was difficult to be positive about what the defendant said. The negative beliefs about the defendant did not persist. Thus, belief perseverance does not appear to provide an adequate explanation.
Hindsight Bias
The cognitive process known as the hindsight bias has also been suggested as a possible explanation for the ineffectiveness of limiting instructions (Casper, Benedict, & Perry, 1989). Hindsight bias refers to a phenomenon where once the outcome to a particular event is known, individuals are prone to overestimate the likelihood that the outcome would have occurred (Fischhoff, 1975). Further, events supporting that outcome are better remembered than events that do not support that outcome, and alternative outcomes seem less likely to have occurred. Such a process may interfere with jurors' ability to ignore information they are aware of, but are instructed not to use, in their decision making.
Casper et al. (1989) examined the hindsight-bias hypothesis. The researchers showed participants a videotaped simulation of a trial involving an illegal search and seizure civil suit brought against two police officers. The outcome of the search was varied, and three conditions were created. In the first condition (guilty outcome), police found evidence of illegal conduct. In the second condition, police did not find any evidence and later arrested a different person (innocent outcome). In the final condition, no outcome information was provided (neutral outcome). Mock jurors were then presented with judicial instructions that were intentionally complex and hard to follow. The instructions defined the criteria for
a legal search and explained the concepts of probable cause, due process liberty, excessive force, preponderance of evidence, and damage awards (actual and punitive). An admonition to disregard outcome information in making a decision about the damages was also included. Participants were told, "Whether the plaintiff... was guilty of a crime at the time of the occurrences testified to in this proceeding is entirely irrelevant and is not to be considered by you in any way in reaching your verdict" (Casper et al., 1989, p. 297). The main dependent variable was the amount of damages awarded to the plaintiff. If jurors correctly follow the instructions, no differences in damages awarded between the three outcomes should emerge. However, if the hindsight bias is operative, there should be greater damages awarded in the innocent-outcome condition and fewest damages awarded in the guilt-outcome condition.
Significantly lower actual and punitive damages were awarded to the defen-dant when participants heard that evidence of illegal conduct was found. These results indicate that the judicial admonitions to disregard outcome were disre-garded themselves. Casper et al. (1989) also found testimony interpretation to be the strongest predictor of damages. Outcome information appears to affect how evidence is encoded, recalled, and retrieved. This process in turn determines how awards are made. Consequently, there was support for the hindsight model. However, it is not clear that the backfire effect of limiting instructions can be accounted for by the hindsight bias. Thus, other theories that can account for this effect may provide a broader and more useful framework for understanding the problems associated with the effectiveness of limiting instructions.
Reactance Theory
Perhaps the most common explanation for the failure of limiting instructions is that judicial admonitions produce reactance in jurors. Reactance theory (J. W. Brehm, 1966; S. S. Brehm & Brehm, 1981) maintains that when individuals perceive that their ability to perform "free behaviors" is threatened, they become psychologically aroused. A free behavior is any behavior in which individuals feel that they have either the requisite physical or psychological ability to engage. From this perspective, the stronger the threat to the freedom, and the more important the perceived freedom, the higher the level of psychological arousal. This arousal produced by threats to free behaviors has in turn been labeled
reactance.
Although the notion of reactance has perhaps achieved its greatest application in clinical settings as therapists seek to devise treatments that will be most beneficial to particular clients (e.g., Shoham & Rohrbaugh, 1997), the theory presents a powerful explanation for the failure of limiting instructions. Initial research conducted to determine how and when reactance will manifest itself demonstrated that when free behaviors are threatened, the attractiveness of the threatened behavior increases. For example, participants who when given a chance to select a music album to keep as a gift are told they cannot select a desired choice subsequently view that option as even more desirable (J. W. Brehm, Stires, Sensenig, & Shaban, 1966). Reactance arousal has also produced increased attractiveness effects for members of the opposite sex (Pennebaker et al., 1979), toys (Hammock & Brehm, 1966), and food such as cookies and
Argentinean deserts (J. W. Brehm & Rozen, 1971; Worchel, Lee, & Adewole, 1975).
Additional responses to reactance include attempting to reestablish one's freedom by attempting to perform the threatened behavior or even the extreme of aggressing against the threatening agent. Obviously (and hopefully), the likeli-hood of physically aggressing against the threatening agent (the judge) is ex-tremely remote in the courtroom setting. However, attempts to perform the threatened behavior are perhaps most relevant to jury instructions because they frequently occur in contexts involving attempts at persuasive communication. For example, in one of the first reactance studies, J. W. Brehm and Sensenig (1966) told participants they were interested in processes involved with impression formation. Consequently, the participant as well as another participant who had arrived earlier (who was actually fictitious) were asked to choose one of two pictures of different people and give their impressions of that person. Participants were told they were also to predict the accuracy of the other (fictitious) partici-pants' impressions and that they would therefore first be given a note from the other participant that mentioned his or her target preference. This note was either intended to limit the participant's perceived freedom and arouse reactance or not arouse reactance. Specifically, participants in the reactance-arousal condition were given a note stating the other person "thought they should select" a specific person, whereas participants in the control condition were simply told of the others' preference (i.e., "I like this person"). The results indicated that participants were more persuaded when the other simply expressed a preference and were more likely to reject the persuasion attempt, leading to a boomerang (or in the present terminology, backfire) effect, in the face of a stronger persuasive message. It should be noted that even in the reactance condition, the threat to choice was rather weak, and Brehm and Sensenig speculated that stronger threats might arouse more reactance and thus further inhibit successful persuasion. Subsequent research has supported this proposition (e.g., Wicklund & Brehm, 1968). Indeed, reactance has been shown to occur even when a communication advocates believing in a position with which the individual initially agrees. For example, participants who either did or did not believe that the Communist Party should be treated just like any other political party became more accepting of the alternative view after reading an essay that said they had no choice but to believe in their original position (Worchel & Brehm, 1970).
In the courtroom setting, jurors may consider their ability to process any relevant probative testimony or information a free behavior. That is, they may feel that they should be the ones to determine relevance, especially if limiting instructions run counter to more global conceptions of justice (e.g., a juror may think that if they follow the judge's instructions and ignore illegally obtained incriminating information, their freedom to punish moral transgressors is being restricted). Thus, with limiting instructions, reactance may be aroused when jurors are instructed that they must disregard potentially useful information that they are aware of (Wolf & Montgomery, 1977). Consequently, the juror may attempt to reduce reactance and reestablish their freedom by performing the threatened behavior. This reaction could in turn occur through a number of processes, for example, if individual jurors privately considered such testimony or if there was jury discussion of the inadmissible evidence during their deliberation. In addition,
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reactance theory predicts that jurors may reevaluate the threatened freedom. The reevaluation would lead to the lost freedom being viewed as more attractive. Consequently, jurors may not only fail to ignore the evidence but may also focus additional attention on it because they see it as being an extremely important piece of information.
Reactance theory then can account for the backfire effect. Recall that several studies have demonstrated that inadmissible evidence accompanied by a judicial admonition is more powerful than evidence not accompanied by an admonition or even admissible evidence. Reactance theory would predict that the greater the threat jurors perceive to exist, the greater the likelihood that they will be influ-enced by inadmissible evidence. If that is the case, then a strong admonition to the jury should result in a stronger effect of the inadmissible evidence than a weak
admonition.
Wolf and Montgomery (1977) empirically tested this hypothesis by present-ing participants with a simulated trial that contained specific testimony that was ruled either admissible or inadmissible. The inadmissible evidence was accom-panied by an admonition that varied in strength. Participants were given either a weak admonition ("I want to remind you that the testimony . . . was ruled inad-missible" (p. 211)) or a strong admonition ("I want to remind you that the testimony. .. was ruled inadmissible. Therefore, it must play no role in your consideration of the case. You have no choice but to disregard it" (p. 211)). When testimony was ruled inadmissible and accompanied by a weak admonition, it did not produce a biasing effect. However, there was a significantly greater effect for inadmissible evidence when the evidence was accompanied by a strong admoni-tion, which is consistent with a reactance explanation.
Similarly, Clark (1994) demonstrated reactance effects in a study on censor-ship in minority influence. Participants in his study were presented with a summary of evidence (adapted from Rose's [1954] play Twelve Angry Men) that clearly indicated a defendant's guilt. Participants were informed of the jury's initial verdict vote (which was an 11-1 split in favor of guilt). However, partic-ipants were told that during the deliberations 1 of the 12 jurors refuted several key pieces of evidence by introducing new information (such as producing a switch-blade knife that was identical to the murder weapon that the juror reported buying the night before). Finally, participants were informed that the judge had been made aware of this new information and considered it inadmissible because it had not been presented during the trial. Consequently, the judge instructed the jurors to ignore it. Clark manipulated the amount of evidence that was ruled inadmissible (participants in a control condition were not given any instructions regarding the inadmissibility of the evidence). Consistent with a reactance explanation, minority influence was weakest when information was considered admissible, stronger when it was ruled inadmissible, and most powerful when it was ruled inadmissible and the minority juror was permanently removed from the deliberations. Note also that this study casts further doubt on the hindsight bias and belief perseverance explanations because from those perspectives initial information regarding the defendant's guilt should lead to discounting of the subsequent exonerating infor-mation in all conditions.
Reactance may also be useful for understanding why the backfire effect occurs for certain types of evidence but not others. Recall that Pickel (1995) found
a backfire effect for inadmissible prior conviction evidence, but not for hearsay evidence, when explanations were presented. This result may indicate that jurors do not perceive the probative value of hearsay to be as great as other evidence that is more direct. Consequently, judicial attempts to limit or ban hearsay altogether may produce lower levels of reactance. This possibility is consistent with the work of other researchers who have found a minimal impact of hearsay evidence (Landsman & Rakos, 1991; Miene et al., 1992; Paglia & Schuller, 1998; Rakos & Landsman, 1991).
Although most studies investigating pretrial publicity have demonstrated antide-fendant biases on the part of participants, under certain circumstances a deantide-fendant leniency effect may also emerge (Mullin, Imrich, & Linz, 1996). Mullin et al. (1996) demonstrated that in a simulated acquaintance-rape trial, male participants exposed to general rape publicity became more prodefendant. General publicity was similar to what would appear in a popular magazine such as Cosmopolitan (e.g., reporting the typical rape incident pattern and experiences of a woman who had been raped). In-terestingly, case-specific pretrial publicity had a minimal impact on men.3 As Mullin et al. argue, the leniency effects of general publicity may be triggered through reactance processes. The general pejorative portrayal of men in the rape articles may have motivated male participants to focus on the possibility of multiple interpretations of the factors that contribute to acquaintance rape. For example, not only is there a victim's side of the story in a rape case, there is also the man's side of the story. Although men may have been aware that multiple interpretations of the events existed, the simulated trial was a one-sided prosecution oriented case. Consequently, male participants may have viewed their free behaviors to consider multiple inter-pretations of evidence to be threatened.
Previous research supports this explanation. For example, Jones and Brehm (1970) observed that the persuasion literature at the time indicated one-sided communications were less persuasive than two-sided communications when the individual was opposed to the position of the communication. On the basis of reactance theory, however, Jones and Brehm hypothesized that all that was necessary for a one-sided argument to be less effective was an individual's awareness of there being two sides to the argument, not that she or he necessarily know any specific pro or con arguments. By just being aware, reactance could be aroused to the extent that the individual perceives the one-sided communication as a threat to their ability to attend to the alternative. In the study by Jones and Brehm, participants were exposed to a one- or two-sided communication consist-ing of a prosecutor's summary to a jury after beconsist-ing (a) told there was persuasive testimony on both sides or (b) given no such information. The results indicated that when participants were aware of multiple sides to the argument, a one-sided communication was less persuasive even when the audience had no initial opposition to the presented position. Perceived bias of the message did not account for the effects, suggesting that the pressure perceived from a one-sided portrayal can lead to reactance.
3It should be noted that in their meta-analysis Steblay et al. (1999) found that general pretrial
publicity was associated with smaller (but still significant) effect sizes compared with specific publicity about the defendant and crime.
In sum, reactance theory predicts that if limiting instructions are perceived as restricting a juror's decision freedom, jurors may be motivated to assert that freedom and attend more strongly to the evidence that is ruled inadmissible. With a rather simple framework, the theory therefore explains the results of a number of studies designed to examine the effects of limiting instructions and the general finding that not only are they ineffective, but they also produce a backfire effect. It should be noted, of course, that a core assumption of this application is that jurors are motivated to retain their decision freedoms in the courtroom context and that limiting instructions are perceived as a threat to that freedom. It might also be the case that, either with certain situations or particular individuals, there will be motivation to be a "good" juror and honor the judge's admonitions. But does this idea imply that such instructions should then be effective? The ironic-process theory of mental control (e.g., Wegner, 1994) suggests otherwise.
Ironic Processes of Mental Control
According to Wegner's (1994) theory of ironic mental processes, any effort at mental control involves a combination of an active, conscious operating process that searches for thoughts indicative of the desired mental state and a more unconscious monitoring process that searches for indicators of unsuccessful mental control. In the case of mental suppression, an individual may desire not to think a particular thought. Thus, the absence of this thought will constitute the desired mental state, and an operating process will initiate efforts toward that end. A monitoring process will subsequently be engaged to check on the success of the operating process, that is, whether or not the thought is indeed absent from consciousness. The irony of the theory's proposition is that the very processes that are engaged to distract the individual from the thought also monitor the possible recurrence of that thought, which in turn may lead to a subsequent identification and increase of the accessibility of that construct.
In a classic demonstration of this process, Wegner, Schneider, Carter, and White (1987) asked participants to think aloud after being instructed to suppress thoughts of a white bear. Participants were often unable to do so and reported frequent intrusions of the thought. From this perspective, the operating process is an effortful search that is resource dependent. As such, when resources are allocated to one task, performance on a juxtaposed operating process will suffer even more. Using this logic, a number of studies have demonstrated that when participants are placed under cognitive load (mental demand; e.g., rehearsing a number, time pressure), which is hypothesized to impair the operating process, the suppressed thought comes to mind even more strongly (e.g., Wegner & Erber, 1992). Ironic rebound effects of mental suppression have been demonstrated across a range of circumstances such as thoughts toward mood control (Wegner, Erber, & Zanakos, 1993), relaxation and sleep (e.g., Wegner, Broome, &
Blum-4Although all of the aforementioned research has explicitly asked participants to suppress a
particular thought, studies have also demonstrated that these rebound effects occur in the absence of specific directives, for example, with thoughts of personal mortality that are hypothesized to naturally instigate efforts toward suppression (Arndt, Greenberg, Solomon, Pyszc/ynski, & Simon, 1997) or under the chronic suppression of depressive thinking (Wenzlaff & Bates, 1998).
