by Dan Simon. Cambridge: Harvard University Press, 2012. 405 pp. Hardcover $45.00. ISBN: 978-0-674-04615-3

Reviewed by Sawyer Sylvester, Department of Sociology, Bates College, Email: ssylvest[at]


It has been suggested that the occasional wrongful conviction is the price society pays for an otherwise creditable criminal justice system. Of course, society pays only in some figurative sense – injustice bites directly on the person wrongfully convicted. Lest some take comfort in the assumption that this happens only rarely, statistics produced by The Innocence Project, among others, show that wrongful conviction occurs with alarming frequency. And if some still believe that such occurrences strike only among suspect populations, the literature increasingly shows that wrongful conviction can be an experience open to all.

A number of studies have shown that the two main causes of wrongful conviction are: first, eyewitness testimony and second, forensic science evidence. Regrettably, these enjoy almost mythic credibility among the public, most of the judiciary, and a major segment of the bar. These types of evidence, as well as other areas of the criminal justice process, involve testimony based on psychological fact – what people can discern, recognize, remember, and relate. Consequently, a close examination of these processes, and their forensic significance, would seem essential to an improvement in our criminal procedure. Simon explores these processes especially in four areas: criminal investigation, eyewitness identification and memory, criminal interrogation, and the fact-finding capacity of the trial process.

Simon begins by exploring criminal investigation as one of the prime sources of error at the very beginning of the criminal justice process. Constructing a credible image of a past event is a difficult task at best and, in our system, persons of varying degrees of skill and experience are involved in its construction. It is also characteristic of the United States that our system of law enforcement is notably fragmented, resulting in significant differences in resources, policies, and a divergence in the understanding of the nature and quality of evidence.
Perhaps the most troublesome feature of the investigative process (although not absent from later stages of criminal procedure) is found in the various forms of confirmation bias.

At the early stages of criminal investigation when facts are few and hypotheses weak, the human tendency is to credit subsequent evidence that supports an initial image of the crime to which the investigator has become attached and either to ignore contradictory evidence or to question its validity solely on the basis of its lack of agreement with prior favored evidence.[*508]

In a way, some of the very evidentiary protections offered by our criminal justice system may contribute to this kind of tunnel vision. At each stage of the criminal process – from probable cause to arrest, to prima facie case for indictment, to the burden of proof for conviction – any re-examination of a prior determination of evidence is closed off by a subsequent satisfaction of a higher order of proof. A sense of finis litem would seem to pervade the entire process and not just the final decision.

Simon also observes that once an offender is identified and an arrest made, any neutrality present in the initial investigation is lost primarily as a result of a shift in the role of the police. Initially fact investigators, the police now become an adjunct to the prosecutor in seeking a conviction. The task is now to strengthen the existing decision, to the exclusion of all other possibilities. This helps the police meet their principal goal which is clearing cases, and the prosecution in its goal of gaining convictions.

Ideally, in our adversarial trial system, the prosecutor can look forward to a vigorous challenge from an advocate for the defense – the presumed equality of forensic arms. All the more so is the tendency for prosecution and police to see themselves as a cohesive in-group joined in a battle for a just cause, which is to win.

Simon describes five mechanisms which lead to the bias he describes: selective framing strategy, which constructs the issue at hand in a manner that tilts toward a desired outcome; selective exposure, which highlights only that evidence relevant to that outcome; biased evaluation, a slanted judgment on the significance of certain evidence; selective scrutiny or paying more attention to evidence that supports or questions an initial hypothesis; and selective stopping, which terminates an investigation at the point where the desired result has been reached – disallowing the search for contrary evidence.

As with the other major sections of the book, this section ends with several specific recommendations to improve the investigative process, perhaps the most important of which is far greater transparency of the entire process itself.

It is likely that for most people eyewitness testimony concerning people and events is given an immediate and unshakable credibility. Many assume that when one witnesses a person or situation, an image is accurately and unchangeably recorded in memory and later may be recalled and related with equal accuracy and undistorted by time. Yet, research has shown that none of this is true. Apprehension is anything but simple and can be influenced by a number of contextual factors, all of which Simon discusses in detail. In like manner, he dissects the processes of memory, recall, and later description of remembered events and people.

Common sense might make the assumption that anyone arrested would naturally conclude the best path to self-preservation is to shut up, sit tight, and demand a lawyer. Yet substantial numbers of arrestees fail to do so. Any person just taken into custody is probably not in the best position to engage a skilled interrogator. And this inequality is especially risky since the [*509] goal of the interrogator may very well be not to discover facts but to reinforce a decision that has already been made, namely, that the arrestee is probably guilty. The prize of criminal interrogation is often not truth, but confession.

Simon brings the considerable body of research on false confessions to an examination of the clues used by interrogators to determine when a suspect is telling the truth and provides a critical analysis of the tactics used in criminal interrogations to elicit admissions and confessions, a regrettably large number of which turn out to be false.

At the end of this section, Simon also offers recommendations for improvement, notably the PEACE method of interrogation, which is a less confrontational and more fact-based mode of questioning adopted in the United Kingdom.

The latter part of In Doubt is reserved for an examination of the trial process. The criminal trial, guarded by its Constitutional guarantees and guided by the extensive rules of evidence, has traditionally been seen as the most effective and accurate method of fact determination. The adversarial winnowing of evidence, the truth testing by cross examination, and the hearty good sense of the twelve good men and true in the jury box have been almost unquestioned as the best the criminal justice system could hope for. Yet, it is far from the best according to Simon.

Many of the problems he describes can be seen as imbedded in the very nature of our Common Law procedure – it is intensely oral. At the beginning, lawyers speak to the jury and tell a story. Lawyers call witnesses, who tell a story about what they have seen and experienced. The jurors, at the end, go off by themselves and talk to one another. They then return and speak the truth – a verdict.

Problems begin with witnesses whose testimony is now an amalgam of what they originally witnessed plus all the influences on their memory that occurred in the time intervening. Also, in that interval, lawyers on both sides have not been idle. They follow the age-old advice to never call a witness to the stand if you don’t know what they’re going to say, and prepare witnesses accordingly – an obvious source of bias.

One of the most troubling defects in our trial system is that jurors only know the final product in the development of evidence. Simon points out that the absence of an accurate investigative record denies the jury the opportunity to critique not only the authenticity of the trial testimony, but also the legitimacy of the techniques by which that testimony was produced.

This feature of our trial process would be especially troublesome in the growing number of cases that involve scientific evidence because it has been shown that jurors place inordinate faith in forensic science of all kinds. Simon then moves on to consider the equally uncritical acceptance by juries of precisely the types of evidence he previously has shown to be so error prone: eyewitness identification, memory of past events, confession evidence, along with alibi evidence, and the ways jurors attempt to judge whether a witness is telling the [*510] truth.

Chapter seven, the last substantive chapter in the book, explores some of the processes of a criminal trial that are not designed to produce evidence or to determine its authenticity but are those integral features of our trial system more directly connected to the ultimate question of guilt or innocence. These are the sacred cows of cross-examination, jury instructions, and the differential burden on the prosecution. These, together with what is often thought of as the final guard against wrongful conviction – appellate review – Simon exposes as seriously flawed.

It is unlikely that any review could do complete justice to a book like In Doubt. The best word to describe the book is encyclopedic. I doubt that there is a single relevant study or commentary in print that the author has neglected to consider, although I confess I have not read through the one hundred and sixty pages of notes. Withal, the book is felicitously written and should be on the bookshelf of anyone who is seriously interested in the psychology of the criminal justice system, the trial process, and the nature of evidence.

Copyright 2012 by the author, Sawyer Sylvester.