Psychology and Law

Claremont Graduate University’s focus on Psychology and Law spans aspects of the legal system ranging from eyewitness testimony to jury selection, from pre-trial interrogation practices to the death penalty itself. With faculty within CGU and across the undergraduate colleges spanning cognitive, developmental, and social psychology, the broad array of research agendas allow graduate students the opportunity to develop their own research in the area of their interest.  You can focus your studies on Psychology and Law by enrolling in the Applied Cognitive Psychology program.

Below are just a few examples of how the faculty, students, and alumni in Claremont have been pushing the envelope on Psychology’s role in the Law.

Recent book publications include:

Expert Psychological Testimony for the Courts
by Mark Costanzo, Daniel Krauss, & Kathy Pezdek

Forensic and Legal Psychology: Psychological Science Applied to Law

by Mark Costanzo & Daniel Krauss

In addition, profiles of current students and recent alumni working in the field are included below.

Kathy Pezdek: Eyewitness Testimony Before the Trial

Cognitive Psychologist Dr. Kathy Pezdek has long explored conditions that affect the accuracy of eyewitness memory. Erroneous eyewitness testimony can result from a range of situational factors as well as from suggestive circumstances, such as biased lineups and suggestive interrogation. Her research findings have informed many juries and decided the fate of the accused in high-visibility trials, in many of which Dr. Pezdek has testified as an Eyewitness Expert Witness.

Recently, though, she realized that courtroom jury trials only make up about 10% of all case files. "It dawned on me," she says, "that 90% of all cases were being decided by attorneys doing back-room plea bargaining, so that’s where we should be looking to see how evidence is evaluated." In response, she is taking her research back one step in the process to look at how attorneys, not jurors, evaluate eyewitness evidence. Dr. Pezdek explains, "If an attorney hears that a defendant was witnessed at a party a year ago and is pointed out in a lineup, they think they have a slam dunk case." This is not necessarily so, however. With the help of doctoral student Stacia Stolzenberg, Dr. Pezdek has found that even the identification of people who are casually familiar can be erroneous. If attorneys were better informed about such psychological findings, out of court settlements could be more accurately resolved by defense and prosecuting attorneys.

The National Institute of Justice's Program on Crime and Justice Research has granted Dr. Pezdek a $250,000 research grant to study this process. A grant of this size is rare in the field of Cognitive Psychology. "This is the exact type of research we want to be doing here at CGU," Dr. Pezdek explains passionately. "This research applies theoretically interesting issues to the real world resolution of criminal cases."

Recent works by Dr. Pezdek:
Pezdek, K. & Salim, R. (2011; in press). Physiological, psychological and behavioral consequences of activating autobiographical memories, Journal of Experimental Social Psychology.

Pezdek, K. Avila-Mora, E., & Sperry, K. (2010). Does Trial Presentation Medium Matter in Jury Simulation Research? Evaluating the Effectiveness of Eyewitness Expert Testimony. Applied Cognitive Psychology, 24, 673-690.

Daniel Krauss: Improving the Reliability of Research on Psychology and Law

Dr. Daniel Krauss, a researcher in the field of Psychology and Law, is interested in "where the field has got it right and where we may have gotten it wrong." One hot topic is the subject of an article co-authored with CGU student John McCabe and Dr. Joseph Lieberman in Behavioral Sciences and the Law. There has always been a controversy over the validity of psychology’s use of mock-trial research. After all, the courts have complained, how reliable can experiments be when the mock juries used in the research are most often made up of undergraduates—a relatively homogenous group of educated, middle-class citizens? In an article entitled "Reality Check," McCabe, Krauss, and Lieberman are contrasting undergraduate mock juries with others drawn directly from a community sample in one specific legal context. They found significant differences between the groups. In this special issue of the journal, which Krauss is co-editing, additional articles explore areas in the law where juror sample differences matter and where they don't. Following their findings, Dr. Krauss and John McCabe are beginning work on a study using real jury pools as their subjects. These pools, which can be difficult to gain access to for many logistical reasons, have been made available thanks to another Claremont connection—CGU alumnus Dr. Dae Lee.

These issues and many more are also surveyed in depth by Dr. Krauss in a book co-authored with Dr. Bruce Sales, one of the original founders of the field of Psychology and Law, currently in preparation and under contract with the American Psychological Association Press. "The book examines the history of psychology and the law, our successes over the years, and where the field should be moving but isn't," Dr. Krauss explains. Additionally, he and Dr. Mark Costanzo have a new textbook on Forensic and Legal Psychology being released by Worth Publishers,  available in early 2011. Dr. Krauss is also launching a project in collaboration with Dr. Stacy Wood and Dr. Jennifer Groscup. This study will explore the influence neuropsychological experts can have on jury decision-making in capital sentencing. "In some cases, the neuropsychological expert will use a graphic display from a MRI scan to show the area of damage. In some conditions, the expert will simply state that the damage is there, and in others the expert will not testify at all. We're expecting the visual representation to strongly sway the jury decision making. It’s a project that looks to be a very interesting collaboration."

"One advantage of the Psychology and Law emphasis here at the Claremont Colleges," Dr. Krauss adds, "is that we have such a strong cross-section of psychologists who are well-published in the area. With two Social Psychologists (Mark Costanzo and Jennifer Groscup), a Cognitive Psychologist (Kathy Pezdek), and my work as a Clinician with social psychology in the mix, it makes for a very well-rounded team."

Recent works by Dr. Krauss:
Krauss, D., McCabe, J., & Lieberman, J. (2011, July 25). Dangerously misunderstood: Representative jurors' reactions to expert testimony on future dangerousness in a sexually violent predator trial. Psychology, Public Policy, and Law. doi: 10.1037/a0024550

Wiener, R., Krauss, D., & Lieberman, J. (2011). Mock jury research: Where do we go from here? A special issue of Behavioral Sciences and the Law, 29, 467-479.

Mark Costanzo: How Jurors are Influenced

Dr. Mark Costanzo has published research on a variety of law-related topics including police interrogation, false confessions, jury decision-making, sexual harassment, attorney argumentation, alternative dispute resolution, and the death penalty. He is author of Psychology Applied to Law (Wadsworth, 2004) and the critically acclaimed Just Revenge: Costs and Consequences of the Death Penalty (St. Martin’s Press, 1997). He co-edited (with Dr. Dan Krauss and Dr. Kathy Pezdek) Expert Psychological Testimony for the Courts (Erlbaum, 2007) and is co-author (with Dr. Krauss) of the new textbook, Forensic and Legal Psychology (Worth, 2011).

Professor Costanzo has served as a consultant or expert witness for more than 100 criminal cases involving coerced and potentially false confessions. In 2008, he was the winner of the Outstanding Teaching and Mentoring Award from the Society for the Psychological Study of Social Issues (SPSSI), and in 2010 he won the Outstanding Teaching and Mentoring Award from the American Psychology-Law society (AP-LS).

Professor Costanzo has been working with CGU students Netta Shaked, Heather Butler, and Katie Vinson on research exploring jury reactions to confessions in criminal cases. The research team is teasing apart what content (both factual and emotional) influence the decisions of jurors.

Recent works by Dr. Costanzo:
Costanzo, M.A., Shaked-Schroer, N., and Vinson, K. (2010). Juror beliefs about police interrogations, false confessions, and expert testimony. Journal of Empirical Legal Studies, 7, 231-247.

Costanzo, M.A. and Gerrity, E. (2009). The effects and effectiveness of using torture As an interrogation device: Using research to inform the policy debate. Social Issues and Policy Review, 3, 179-210.

Jennifer Groscup: The Use of Expert Testimony in Court

The work that citizens do as jury members is a funny thing. The judicial system insists that juries strive for evidence-based decision-making and impartiality, and then requires them to listen to lawyers trained to influence their decisions using hard evidence as well as persuasive tactics. Dr. Jennifer Groscup has a lifelong fascination with this contradiction, and conducts studies focused particularly on the effects of expert witnesses on a jury. “One strain of my research is geared toward helping jurors make clear, informed decisions,” she says. “The general public rarely has the expertise to recognize a sham expert from a reliable one, so I’ve looked to the courtroom procedures themselves to see if there is something that can help. We’ve looked at cross-examinations, testimony from opposing experts, and jury instructions to see if anything can make a difference. They have varying degrees of effectiveness, but none is really satisfactory.”

When the language or concepts become too difficult, jurors often resort to using other methods to decide if they trust an expert’s testimony. The information used is often unrelated to the data being presented. “We’ve looked at the quality of presentation, the complexity of the message, and even the attractiveness of the expert. My research team is now assessing how gender affects credibility. Our hypothesis is that attractiveness will be a bonus for male experts and a detractor for female experts.” Dr. Groscup is interested in recruiting new CGU graduate students onto the team.

Her interests have also extended to the persuasion of Judges. “Persuasion affects Judges as well as juries,” she says. “I’m interested in looking at how able Judges are to recognize good scientific testimony or the quality of expert witnesses. The overall thrust is to improve the use of scientific testimony in court.”

“I’m also collaborating with Professors Dan Krauss and Stacey Wood on a project looking at the impact of adding imagery to expert testimony.” For more on this project, see the bio of Dr. Krauss, above.


Iris Blandon-Gitlin: Improving the Detection of Deception

Assistant Professor and Researcher on Legal Psychology
California State University, Fullerton
Ph.D. Claremont Graduate University, 2005

CGU alumna Dr. Iris Blandon-Gitlin has been at Cal State Fullerton working on various research projects addressing issues at the intersection of Psychology and Law. Some of those projects involve applied questions that directly inform police practice. In one recent project Dr. Blandon-Gitlin and colleagues developed an interview technique that increases investigators’ ability to accurately discriminate between liars and truth-tellers.

"Detecting deception in forensic settings is no better than flipping a coin, and the error rate in classifying an innocent person as guilty is alarming high," says Dr. Blandòn-Gitlin. Reasoning that these errors are partly due to the accusatory nature of interview protocols whereby innocent people show signs of arousal not because they are guilty but because they are scared of being the subject of an investigation, Dr. Blandon-Gitlin developed an information-gathering approach in which the questioning style is challenging to liars but not to truth-tellers. "What we want from applied research is to go beyond demonstrating that something is not working, and actually provide workable solutions. The criminal justice system will be more open to our research if we provide solutions that help them accomplish their goals," she says. Her other research projects on risk factors for false confessions and errors in eyewitness identifications also attempt to provide solutions to institutional problems that undermines the process of justice.

Dae Lee: Improving the Court System (and How We Study It)

Research Analyst
Superior Court of California, County of Orange
Ph.D. Claremont Graduate University, 2010

Dr. Dae Lee has found a unique way to help give back to his alma mater—by assisting with access to real jury pools for psychology and law research. Lee, who recently graduated with a dissertation focusing on how jurors react to information about mental disorders in sexual predator trials, began working for the Superior Court of California, County of Orange in 2007, while still enrolled in his doctoral program. "I really like my position here as a Research Analyst in the Planning and Research Unit," says Dr. Lee. "I work with some great people on a variety of interesting projects, dealing with the judicial system first-hand. Our 'customers' are generally court managers and Judicial Officers assisting them with research requests and special reports. We also provide guidance to our collaborative courts—drug courts, mental health courts, homeless courts, and the like, and we also get grants from federal and state levels to examine the effectiveness of these specialized courts. A high priority for our unit is to validate the data in our case management systems for all of our case types (e.g., juvenile, felony, family law, and civil cases), in order to provide our managers with accurate caseflow information. It goes a long ways towards making the system more efficient. The California court system has a strong emphasis on improving fairness in the courts, and I see a lot of potential for future studies."

Thanks to continued connections with Professor Dan Krauss and his current students, Dr. Lee has opened the doors to more accurate subject pools for studies in Psychology and Law. "When jurors are released, usually in the mid-afternoon when they’ve already taken a day off of work, we ask them if they'd be willing to stay around and be paid to participate in a study. This gives a real-world sampling of the jury pools from a community, and may offer much more accurate information about jury reactions."

Stacia Stolzenberg: Children in the Legal System - Testimony and Dependency

Doctoral student Stacia Stolzenberg is looking at the delicate question of possible pitfalls in the use of child witnesses in trials. On her internship with Professor Tom Lyons of USC (whom she met thanks to a connection with Dr. Kathy Pezdek at CGU), she is teasing apart the transcripts from real courtroom testimony in sexual abuse cases. "Context can be very important," she says. "For example, if a child is asked in court whether her parents talked to her about how to talk in court, the child will probably take the question at face value not understanding the subtext of the question—that the court needs to know if she was 'coached' to distort her testimony. One of the things we're looking at is the question of at what age the cognitive ability develops to help children understand the kinds of questions being put to them during a trial. We're looking at transcripts of actual testimony and are also developing an experimental test to see if we can duplicate our hypothesis in a lab. This is part of a larger research agenda looking at children's experience in the court system and under what circumstances their testimony and disclosures can be considered reliable."

Stacia has also become deeply involved with Dr. Pezdek's research on eyewitness memory, examining how accurately individuals can assess whether a face is familiar to them. Working in several high schools in Los Angeles, she and Dr. Pezdek are testing face recognition among the school's current students by using yearbook photos of recent alumni. "The implications for Psychology and Law are important because of how easy it is for people to make mistaken recognitions," she explains. "They sometimes will even fill in additional information, like 'I am sure that the accused is the perpetrator; I remember him from junior high,' when in fact this memory is erroneous."

While still working on her doctoral portfolio, Stacia is taking her Psychology and Law work out into the real world. She and fellow student Kelly Murphy are conducting an evaluation of the Edmund Edelman Children's Court in Los Angeles County, the largest dependency court in the nation. The court, which deals with the over 70,000 children placed into the care of the L.A. County Department of Children's Services each year, has asked Stacia and Kelly to develop an evaluation of their new case assignment procedures, known more formally as the Geographical Distribution Program. The proposal is underway, and Stacia reports being very excited by this opportunity. "It is very rewarding to see our research applied so effectively."

Matthew O'Brien: Facial Recognition and Police Lineups

An eyewitness in a case is shown a group of suspects and asked to identify the assailant in a crime. It's a classic scene from courtroom dramas, but a technique riddled with complications. Among others, reports doctoral student Matthew O'Brien, the eyewitness may actually have more trouble recognizing the guilty party when he was initially observed with other suspects rather than alone. His current project is done in collaboration with Dr. Kathy Pezdek and fellow graduate student Corey Wasson. "We're looking at the Cross-Race Effect, and how this effect is impacted by faces presented individually versus in a group," Matthew says. "The Cross-Race Effect describes the situation in which people tend to have more trouble encoding, and therefore recognizing, the face of someone from another racial group than someone from their own. This has always been a stumbling block for the legal system where the need to assess the reliability of cross-race identifications is common."

While the Cross-Race Effect is well established in the cognitive psychology literature, the current study is testing it in a group context, in which the principles of social psychology, for example out-group homogeneity, are likely to come into play. "What we've found is that identifications of people initially viewed in a group are less accurate than when they are viewed alone, even when the viewing time per face is the same. This might not be surprising. But what's been interesting is that viewing a target face in group of faces impairs face identification for cross-race faces but not same-race faces. This suggests that race is more salient when people are viewed together in a group, and increasing the salience of race exacerbates the magnitude of the Cross-Race Effect. We have three additional experiments underway in which we are assessing why this occurs."

Matthew is also involved in Dr. Pezdek’s study on the questioning of suspect identifications in pre-trial arraignments.