Understanding Pretrial Publicity

Prejudicial pretrial publicity (PTP) constitutes a serious source of juror bias. The current study examined differences in predecisional distortion for mock jurors exposed to negative PTP (NPTP) versus nonexposed control participants. According to work by K. A. Carlson and J. E. Russo (2001), predecisional distortion occurs when jurors bias new evidence in favor of their current leading party (prosecution or defense) rather than evaluating this information for its actual probative properties. Jury-eligible university students (N = 116) acted as jurors in a mock trial. Elevated rates of guilty verdicts were observed in the N-PTP condition. Predecisional distortion scores were significantly higher in the N-PTP condition and reflected a proprosecution bias. The effect of prejudicial PTP on verdict outcomes was mediated by predecisional distortion in the evaluation of testimony. Results are discussed in relation to motivated decision making and confirmation biases. Jurisdictions upholding the notion of a free reporting press in conjunction with a lay jury system face potential problems associated with pretrial publicity (PTP). Depending on the trial and legislative reins on the press within a particular jurisdiction, publicity may reach potential jurors in a combination of extended, graphic, emotional, and judgmental communications about the defendant, victims, and key witnesses (Kramer, Kerr, & Carroll, 1990; Ogloff & Vidmar, 1994; Wilson & Bornstein, 1998). The juror's ability to objectively and rationally consider the evidence and ultimately reach a verdict based only on the evidence presented in court may be hindered by this pretrial information. Although a small number of studies report null effects (e.g., Bruschke & Loges, 1999; Freedman & Burke, 1996), over 35 years of research examining the effects of PTP has produced a considerable body of literature that demonstrates a prejudicial impact of PTP on juror decision making (see Linz & Penrod, 1992; Studebaker & Penrod, 1997, for reviews; see also a meta-analysis conducted by Steblay, Besirevic, Fulero, & JiminezLorente, 1999). Broadly, this research identifies a negative impact of PTP on juror perceptions of the defendant's criminality and likeability, in addition to an increased frequency of guilty verdicts. Much PTP research has been driven by a focus on the practical problems of juror prejudice and the evaluation of practical solutions. Hence, theoretical inroads to explain precisely how pretrial publicity comes to influence a juror's verdict are relatively limited. Researchers have recognized this deficit in the literature (e.g., Kovera, 2002; Devenport, Studebaker, & Penrod, 1999) and acknowledge that research “that investigates the cognitive processes that produce these media effects can inform a search for remedies to media bias” (Kovera, 2002, p. 69; also Linz & Penrod, 1992). In response, PTP research is now moving into what has been identified as its “second generation” with a greater focus on explaining the PTP effect within relevant cognitive frameworks (Fulero, 2002). In this vein, recent research has expanded to examine the impact of general noncase specific publicity (Kovera, 2002); the effects of emotional versus factual publicity (Honess, Charman, & Levi, 2003), midtrial publicity (Vidmar, 2002), and the impact of pretrial publicity in civil litigation (Bornstein, Whisenhunt, Nemeth, & Dunaway, 2002; Robbennolt & Studebaker, 2003). More generally, the decision-making processes of both individual jurors and juries (unfettered by PTP exposure) have come under considerable theoretical scrutiny in the past thirty years, and several models of juror decision making have been proposed and tested. Hastie (1993) broadly identifies two main types of decision-making frameworks, namely mathematical models and explanation-based approaches. Mathematical approaches tend to characterize the task of the juror in terms of a series of mental calculations resulting in an assessment of guilt (e.g., Kerr, 1993; Schum & Martin, 1993; see also Hastie, 1993). However, as a number of authors have pointed out, these models have limited predictive ability given their reliance on conceptualizing trial evidence as discrete units of information (Greene et al., 2002). Explanation-based accounts focus on the way in which jurors make sense of the trial information and seek to construct or organize an explanatory coherent mental representation of the information they receive. The story model for juror decision-making (Pennington & Hastie, 1986) is the most influential approach of this type and proposes that jurors formulate a plausible story of the crime, and subsequently, arrive at a verdict consistent with that particular story. Thus, story construction constitutes a central feature of the cognitive process implemented by jurors to handle trial information in a courtroom setting. As pretrial publicity typically exerts a cognitive impact in advance of the trial and testimony evaluation, an examination of the process by which the publicity information feeds into the decision-making process is necessary. For instance, it may be the case that PTP works to make one “story” more credible than other competing explanations of the crime event or, as is examined in the current article, it may be the case that exposure to PTP promotes a proprosecution bias that determines the subsequent evaluation of each piece of evidence to produce a particular final proprosecution story. It is not an entirely novel suggestion that PTP might act as a type of filter and promote the credibility of one story over another by causing a bias in the processing of evidence. For instance, Linz and Penrod (1992) have suggested that PTP might influence the probative weight assigned to various pieces of evidence by jurors, or even simply bias their interpretation of how important a particular piece of evidence is. In line with predictions of the story model, PTP may alter evaluations of the credibility or plausibility of the evidence, consequently altering the explanatory stories constructed at trial (Linz & Penrod, 1992). This notion of juror decision making as a dynamic process of cyclical updating can be located within human information processing frameworks such as that proposed by Neisser (1976). The central assumption of such frameworks is that knowledge in the form of particular schemas or mental models leads to the expectancy of particular kinds of subsequent information, and that an activated schema will “increase receptivity to particular aspects and interpretations of the available information” (Adams, Tenney, & Pew, 1995, p. 88) in a cyclical “set-reset” process. Somewhat similarly, Montgomery (1983) has argued that prior to choice, decision makers may structure available information such that a leading alternative emerges and dominates other options. Although it is well documented that people distort responses in favor of a chosen alternative after a decision has been made in order to reduce cognitive dissonance (Elliot & Devine, 1994; Fazio & Cooper, 1983; Festinger, 1957; Frey, 1986), the distortion of information prior to reaching a final decision has received less direct attention in legal settings. However, research on confirmation bias has long acknowledged a primacy effect whereby individuals form their opinions early in the decision-making process and then evaluate new information in a way that is favorable to that initial opinion (Anderson & Jacobson, 1965; Nisbett & Ross, 1980). Similarly, research relating to belief persistence has suggested that when an opinion has been formed it can be very resistant to change even when shown to be incorrect (Rhine & Severance, 1970; Ross & Lepper, 1980; Ross, Lepper, & Hubbard, 1975). As a result, decision-makers may be more likely to view new ambiguous information as confirming previous beliefs or opinions and are more likely to dismiss information disconfirming initial opinions (Ross & Anderson, 1982). The notion of predecisional bias or distortion allows a more precise conceptualization of these general processes within the decision-making context. Recent work by Carlson and Russo (2001) on predecisional distortion in mock jurors provides a useful platform from which to explore the impact of PTP on the evaluation of evidence in an experimental setting. Predecisional distortion has been defined as the “biased interpretation and evaluation of new information to support whichever alternative is currently leading during a decision process” (Carlson & Russo, 2001, p. 91; see also Russo, Medvec, & Meloy, 1996). This particular bias has considerable implications for the juror's task and may have even greater implications where there has been exposure to PTP. Taking Carlson and Russo's example, assume two jurors are exposed to a new piece of evidence concerning a defendant in a trial with two possible outcomes for that defendant: a guilty verdict or a not guilty verdict. Both jurors have been presented with precisely the same evidence up to this point although Juror A currently favors the defendant's case as stronger or in the lead, whereas Juror B has been persuaded by the evidence that the prosecution has presented a superior case. Predecisional distortion proposes that when presented with a new item of evidence both jurors will evaluate that evidence in a way that is more favorable to their current leading opinion rather than evaluating it in a more objective fashion. In other words, jurors distort their evaluation of the evidence toward their own current leader and away from the actual probative value of the evidence (for further explanation see Carlson & Russo, 2001). Research indicates that this distortion may occur without the influence of prior beliefs or early choice (Meloy, 2000; Russo, Meloy, & Wilks, 2000). In the first study of its kind examining predecisional distortion in a legal setting, Carlson and Russo (2001) found that mock jurors committed distortion in both civil and criminal mock trials, despite repeated instructions to avoid preemptive judgments. The authors concluded that jurors are likely to be unaware of their predecisional distortion and that the process is essentially a coherence-based mechanism. In summary, Carlson and Russo proposed that, rather than grappling with multiple stories when constructing a representation of a crime, jurors hold a single dominant story (derived from the leading verdict at that point) which accounts for the evidence already received. That story might well be radically altered by the acquisition of new information, but the predecisional bias may make it more difficult to shift to diametrically opposed alternatives (verdicts). Thus, the key, applied problem highlighted by this research is that mock jurors (in common with participants in other, nonlegal settings) display a tendency to distort their evaluation of new information (e.g., evidence) in favor of an existing preference rather than to conduct an objective assessment of that information avoiding any premature judgment. The current study aims to extend Carlson and Russo's (2001) work by using the predecisional distortion measure to examine how exposure to PTP might influence the way in which jurors evaluate testimony on the grounds that prejudicial PTP may develop a pretrial outcome or verdict bias. The PTP bias is typically manifested in an increased rate of guilty verdicts, but not a great deal of information is available about how that particular outcome is actually reached. Little research has examined the process by which jurors who have been exposed to prejudicial PTP evaluate evidence as they receive it, how these online evaluations influence subsequent evaluations, and, ultimately, verdict outcomes. Although Carlson and Russo's study found that prior beliefs concerning the legal legitimacy of a typical case did not influence case decisions or distortion scores, it is not clear how beliefs or impressions concerning a defendant generated by PTP might influence the evidence evaluation and hence, leader identification and subsequent predecisional distortion.