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In Doubt: The Psychology of the Criminal Justice Process (Dan Simon)USC Gould School of Law
Harvard University PressUSC Gould School of Law
Harvard University PressHarvard University Press

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Q&A For In Doubt: The Psychology of the Criminal Justice Process
By Dan Simon
Published by Harvard University Press (2012)

1. What can psychological research contribute to our understanding of the criminal justice process?

The criminal justice process is operationalized by people: witnesses, detectives, lawyers, judges, and jurors. Their performance is a function of their cognitive functioning: remembering events, recognizing faces, judging people's truthfulness, drawing inferences, making judgments, and more. Experimental psychological research can teach us how well people perform these tasks and, importantly, how their performance can be improved. Fortunately, we have at our disposal a vast body of pertinent research.

2. In a nutshell, what in your view is the problem with the criminal justice process?

The key problem revolves around the questionable accuracy of criminal verdicts. The human testimony from which verdicts are made is habitually incomplete and contains an unknown mix of accurate and erroneous evidence. The questionable nature of the evidence casts a doubt over the accuracy of the verdicts that the system produces.

3. Everybody knows that people occasionally make mistakes? Shouldn't we deem human error an acceptable limitation of the criminal justice process?

Indeed, the exoneration cases show that on occasion, the mistaken evidence stemmed from plain human error. We can call these spontaneous errors. Far more often, however, the mistaken evidence was induced by the legal process, typically, by inadequate police procedures. The vast majority of investigative procedures conducted today are based not on research, but on age-old intuitions and habits. The research shows the many ways in which these procedures can go wrong, and provides a detailed framework for correcting them. It is incumbent on us to reduce the induced errors to an unavoidable minimum. The reforms proposed in this book are designed to do just that.

4. Can't we fix the problems by identifying the bad apples in the ranks of the law enforcement agencies? In other words, wouldn't increasing the scrutiny of police officers and prosecutors prevent mistaken prosecutions?

True, some false prosecutions stem from the misconduct of police personnel and prosecutors. These instances do indeed warrant that we pay more attention to instances of professional misconduct and respond more forcefully to them. But it cannot be overemphasized that errors occur even when everybody involved behaves honestly and professionally. The problems lie in the procedures themselves; hence the need for reforming the procedures.

5. What is so wrong with the evidence that we use in criminal trials?

One of the consistent observations from the exoneration cases is that the testimony that witnesses gave at trial was dramatically different from the statements they originally gave the police (which are generally more accurate). Invariably, the trial testimony was more incriminating than the original statements. Trials are conducted months and even years after the criminal event. During this time, witnesses' memories grow weaker due to decay and become more contaminated from exposure to extraneous information. This information can originate from co-witnesses, police detectives, prosecutors, defense attorneys, and the media.

6. You cite that in multiple cases where a person has been falsely convicted, the reason is that there was an "escalation of error" on the part of detectives investigating the case. What safeguards can be put in place to prevent this from happening?

The escalation of error (also known as tunnel vision) is fueled by both cognitive and motivational factors, which are for the most part pretty resilient to intervention. The best way to minimize this phenomenon is by placing investigations in the hands of open-minded and self-reflective investigators, and by cultivating an investigative culture that promotes scrupulous and inquisitive thinking.

7. Pressure from the community to solve cases adds pressure on the investigative teams. Can this lead to subpar investigative work or over-zealous prosecutions?

The exoneration cases indicate that false convictions are most likely to occur in high profile cases, that is, when the police and prosecution experience particular pressure to clear the case and punish the putative perpetrator. These observations from real life cases are consistent with laboratory studies that show that the presence of strong goals tends to distort people's reasoning process to achieve those goals.

8. Should we be worried about the accuracy of witness identifications?

The recognition of strangers is one of the most common causes of error in criminal prosecutions. While this seems on its face to be a straightforward and simple task, it is actually very complex and error-prone. The key statistic here is that about one of three every times that witnesses pick a suspect at a lineup, they are mistakenly picking innocent fillers.

9. What is inherently wrong with the identification procedures used by the police and what can be done to reduce mistaken identification?

The accuracy of identifications is exquisitely sensitive to the manner in which the procedures are conducted. For example, one study showed that slight variations in the procedures used resulted in swings in the rate of accuracy from 14% to 86%. The book offers more than a dozen specific recommendations on how to conduct identification procedures properly. Notably, the person administering the procedure should be blind to the identity of the suspect; the fillers should be chosen carefully to make for a meaningful test of the witness's memory; and correct instructions should be given to the witness. Ideally, the entire process should be videotaped.

10. What role does the interrogation process play in obtaining false confessions from innocent suspects?

Interrogation processes are one of the wildcards of criminal investigations. While some suspects confess genuinely out of their free will, most confessions are obtained only after subjecting the suspect to a highly confrontational and aggressive process. Interrogation methods work their magic by means of driving suspects into states of submission and by altering their perception of the available courses of action so as to make confessing seem like the most advantageous choice. Not surprisingly, many suspects recant their confessions as soon as the investigative pressures recede.

11. What makes confessions such powerful evidence?

Confessions have been described by the Supreme Court as the "bombshell that shatters the defense." That is because jurors are strongly inclined to believe them. Most confessions contain a rich narrative of specific details about the criminal event which were not known to the general public. However, this richness of detail does not really corroborate the incriminating statements. Not surprisingly, innocent suspects who can be persuaded to confess to a crime they did not commit, can also be persuaded to sign off on details they do not really know.

12. I would never confess to a crime that I did not commit. Why should I believe somebody's claim of innocence after they have confessed to the crime?

Indeed, 90% of people believe that they would never confess to a crime they did not commit. But herein lie two problems. First, people tend to overestimate their powers to resist social pressures. In the famous studies on Obedience conducted by Stanley Milgram in the 1960s, vast majorities of observers estimated that they would not comply with the instructions to electrocute their counterparts but, in reality, a large majority did obey the brutal instructions. You can be sure that usually the pressures in police interrogation rooms far exceeds those experienced in the Milgram laboratory. Second, it is unclear why this belief should lead to the rejection of claims of innocence. It is equally, if not more, self-defeating and counter-intuitive for guilty suspect to admit their guilt to the police.

13. Can't mistakes in the evidence be uncovered and corrected at trial? Isn't that the whole purpose of the criminal trial?

Unfortunately, the criminal trial is not well equipped to identify the mistakes in the evidence. Reconstructing complex and ambiguous past events is a very difficult feat, and criminal trials are not an optimal setting for performing this delicate task:

  • as mentioned, the witness' memories are often contaminated during the long periods leading up to the trial
  • the evidence is typically devoid of indicia of its reliability;
  • jurors are not presented with nuanced and impartial statements, but are forced to choose between two stories that are habitually exaggerated if not grossly distorted;
  • many of the key witnesses have obvious stakes in the outcome of the case (notably, the defendant and the victims), and others are often aligned with one of the parties;
  • much of the testimony follows on the heels of "witness preparation" by the lawyers;
  • the police investigation is rarely recorded, which prevents jurors from knowing what factors might have influenced the testimony;
  • determinations of reliability often boil down to swearing contests between the police and the defendant.

14. Are you saying that the criminal trial is not an appropriate way to determine guilt?

By its nature, the criminal trial is not an optimal setting for performing the delicate fact-finding task. The jurors' decision is susceptible to manipulation and is exposed to extraneous influences: for example, lawyers deploy a host of rhetorical strategies; jurors are often exposed to potentially biasing impermissible evidence; and at times, the facts of the case arouse intense feelings of anger and disgust, or they evoke prejudice towards the defendant.

15. But what about the intricate procedure of the trial -- adversarial argument, cross-examination, jury instructions, and jury deliberations -- don't they guarantee accurate decision making?

The research indicates that the mechanisms that you mentioned are hardly as effectual as they are deemed to be. Cross-examination is oftentimes ineffective and can even backfire; some jury instructions are miscomprehended by lay jurors, and others require impossible mental gymnastics; jury unanimity if often achieved by means of social pressure that is not necessarily related to accuracy.

16. With so much research showing the flaws in both the investigative and adjudicative phases of the criminal justice process, can the American people ever be confident about criminal verdicts?

Yes, in many cases they can. In many instances, the defendant's factual guilt is beyond doubt, such as when the suspect is known to be the victim's ex-partner, was caught in the act, or was identified by means of DNA evidence, surveillance video, or the like. These cases require minimal police investigation, and they are habitually solved through the process of plea bargaining. In contrast, many other cases are ambiguous and complicated. These are the cases that put the system to the test, in that they require greater investigative and adjudicative involvement. In this latter category of cases, the veracity of the verdict will often remain in some doubt.

17. The criminal process is rife with advantages given to the defendant: the presumption of innocence, the high burden of proof, double jeopardy, and the access to appellate courts. Why do you argue that criminal defendants are disadvantaged?

True, as you point out, the criminal procedure affords defendants a number of well-known advantages over the state. Yet when it comes to the all-important issue of the evidence, the defendant is habitually at a substantial disadvantage. The vast majority of criminal defendants lack the resources, expertise, and legal authority to investigate crimes effectively, and are often in custody throughout most of the process. The state typically has the resources, the access to the crime scene, and the power to subpoena and arrest. In effect, the prosecution has a virtual monopoly over the evidence. Still, its duties to share its evidence are rather limited. Oddly, criminal defendants are entitled to considerably less information about the evidence poised to deprive them of their liberty than are litigants in simple contract or tort cases.

18. Isn't airing live testimony in open court the best and most fair method for discovering the truth?

When this practice was originated, centuries ago in England, it probably was the best available method. However, the possibility of creating a video recording of the witness' original statements has opened the door to a far superior way to preserve human testimony. There is no reason to stop presenting evidence orally in open court, but the testimony should be done in the shadow of the witnesses' original statements, which are typically the best approximation of the truth.

19. False conviction is a troubling feature of our judicial process. Knowing that false convictions exist, should we abolish the death penalty?

The thought that innocent people could be put to death should indeed make us think harder about the death penalty. Indeed, this notion played a role in the debates that have led to the abolition of the death penalty (in the past 5 years, 5 states have abolished their death penalty regimes). The issue of innocence is currently reverberating in the state of California, where the abolition of the death penalty is on the ballot for this November.

20. Why did you write this book?

Let me mention two of the many reasons for writing the book. First, I lament the fact that in current practice, the accuracy of criminal verdicts is of secondary importance. The recommendations offered in this book are intended foremost to promote the accuracy of verdicts. Second, the debate surrounding criminal law does not benefit enough from the vast body of experimental psychological research. I hope to help facilitate the understanding and use of this very beneficial literature.

21. What are the central recommendations that you make in the book?

The recommendations fall into two types. First, all investigations should follow best practice procedures that will be based on valid scientific research. Specific recommendations are provided at the end of each chapter. Second, the evidence should be made transparent. This can be achieved by means of creating a digital recording of all of the encounters with human witnesses: all identification procedures, interviewing of witnesses, and questioning of suspects.

22. What do expect will be gained by videotaping encounters with witnesses?

Access to the investigative record should help fact-finders determine whether the testimony might have been induced or otherwise biased by the investigation itself. The availability of a record will effectively force witnesses to testify under the shadow of their own original statements. The existence of the record should also reduce any pressures that might be applied on them to alter their testimony, and serve as a guarantee for their safety. Creating a record should also bear a favorable impact on the investigations themselves. The record should increase investigators' sense of accountability for the way they conduct their investigations. The record should help ensure that investigators adhere to best practices by providing law enforcement agencies with a tool for training, oversight, and quality assurance, and it should also help deter police misconduct. The record is also bound to serve as an informational tool by capturing forensic details that would otherwise be missed.

23. How do you envision a criminal process that elected to adopt your recommendations?

The recommendations offered in this book would enhance the integrity of the evidence used in criminal trials by making it more accurate and transparent. This should reduce the incidence of faulty prosecutions and frivolous defense claims, and thus also curb the number of appeals, habeas corpus proceedings, civil suits, and damages payouts. The precious resources of the court system would no longer be expended on conjecturing what transpired at the police station or in the back seat of a patrol car. Those quandaries would be solved instead by a simple click on the Record button of a video camera. A transparent system should also reduce the distrust and acrimony between prosecutors and defense attorneys, and enable them to interact in a more professional and respectful manner.

24. No complex social system, such as the criminal justice process, can be expected to operate flawlessly. Isn't it fair to say that the process works well enough?

No. As the late judge Jerome Frank once stated, convictions of innocent persons are acceptable "only if they are inevitable—that is, only if everything practical has been done to avoid such injustices. But, often, everything practical has not been done."