Wrongful Conviction Studies Highlight the Need for Ethical and Methodical Defense Investigation Using the Component Method

David Childe, PI BYTES, March, 2006



Since 1988, the advent of DNA testing and more vigilance in general has resulted in over 340 innocent people being released from death-row or lifetime prison sentences.1 This happy outcome, however, merely hints at the extent of the underlying problem of innocent people being found guilty in the first place. After all, DNA testing can only be used to exonerate an extremely small minority of those wrongfully convicted – this sample is by-and-large confined to murder and rape cases where bodily fluid evidence is still preserved and for which the accused was sentenced to death or long-term imprisonment. Extrapolating the data to all felony incarcerations over the last fifteen years would result in a total number of wrongful convictions in excess of 29,000.2

Perhaps the most salient points to emerge from these exonerations are tangible evidence, in microcosm, of how pervasive the wrongful conviction problem is and what the defense investigation industry can learn from it – with particular emphasis on pro-active deployment of The Component Method of Investigation towards the critical areas of focus identified by the in-depth case studies that wrongful conviction cases afford. These areas encompass but are not limited to inaccurate witness testimony, police and prosecutorial misconduct, jailhouse informant testimony, false or coerced confessions, and junk science. This paper will focus on the first two, which are not only the most pervasive but also well within the purview of the defense investigator.


Grace Castle, the well-known private investigator and writer, is particularly vocal about this role – stating that of the cases she has reviewed “none had had the assistance of a professional, competent [private] investigator”. She goes on to point out that “Either the defendant’s attorney or the [private] investigator, or both, plainly had decided that this person was guilty and thus no effort, or at least very little effort, was put forth to assure a fair trial.” 3

Although proper application of the component method cannot magically produce private investigators for cases, it can certainly ensure that they will be handled with nothing less than the highest degree of integrity. According to Perron’s Uncovering Reasonable Doubt, in utilizing the component method of investigation “the criminal defense investigator should only be concerned with seeking and pursuing the truth…remain impartial and objective at all times…conduct all investigative tasks in a professional, ethical, and moral manner.” 4

It is incumbent on the ethical private investigator to only work with high-integrity lawyers. Other than through some type of spiritual conversion, psychologists generally agree that our personalities and values change little after age thirty. Thus, it becomes a pointless effort to try and change a lawyer’s underlying philosophy regarding his clients. Multitudes of solid investigative work performed on a case will be entirely subverted after falling victim to the negative filtering system of a closed-minded defense attorney. Given the unfortunate dearth of highly trained and competent criminal defense investigators, the good ones do indeed have the luxury of being choosy with whom they work.

The twin (and interrelated) problems of misidentification and misconduct highlighted in this paper make a good working relationship with the defendant of the utmost importance. As Perron states, “the interview with the defendant can make or break a case.”5 This means, first and foremost, not prejudging the defendant. Frankly, this should not be a particularly difficult task if the investigator has even a fleeting knowledge of the wrongful conviction literature. A solid measure of empathy for the defendant and active, impartial listening to the defendant during the interview process (the second component of Perron’s method) is also key – not only because it is the morally-correct thing to do but also because eyewitnesses and alibi witnesses known to the defendant (and perhaps not present in the discovery documents) could prove to be case-turners. It can be assumed by the defense investigator that the discovery material provided by the prosecution will oftentimes fall well short of being exhaustive.


Each study that we have evaluated lists this factor as the most pervasive, and by a wide margin. Moreover, it is axiomatic in the legal community that seemingly credible eyewitness testimony (if provided) is the most decisive factor in a felony trial. The inaccuracies are not necessarily of the perjured variety, either. Human perceptions, particularly under stress and with respect to members of other races, are eminently fallible.

A seminal study by Samuel Gross of the University of Michigan Law School found that 64% of the 340 exonerations analyzed from 1989-1993 involved at least one eyewitness misidentification. In 60 of the 340 cases, the false accusation was deliberate.6 A 2001 Northwestern University School of Law Study analyzing 86 cases of legal exonerations found that eyewitness testimony played a role in the convictions of 53.5% of the defendants and represented the only evidence against 38.4% of them. Only one eyewitness testified in 69.6% of the relevant cases. Moreover, potential eyewitness bias can be inferred in that 32.6% of the eyewitnesses were accomplices and had incentives to testify ranging from sentence leniency to full immunity and another 19.6% were non-accomplices motivated by either a grudge or by prosecution consideration in a pending case.7

Interestingly, this plague of misidentification has been known for a long time, having first been identified in scholarly fashion by Professor Edwin Borchard in his classic 1932 book Convicting the Innocent.8 Yet it has taken the numerous recent exoneration studies to bring this mass tragedy to light. So the question for the defense investigator now naturally becomes: What are its causes? Our review of the research has identified the following:

· Unscientific and prejudicial police line-up and photo viewing procedure;

· The susceptibility of eyewitnesses to suggestions by police, whether intentional or unintentional;

· An oftentimes sub-conscious desire on the part of the victim to feel that justice will prevail in some form;

· Research by Loftus specifically that indicates that false memories can be triggered in up to 25% of individuals merely by suggestion, that violent events significantly decrease the accuracy of memory, and that memory can be interfered with and altered simply by giving incorrect post-event information.9

· Research by Wells specifically that indicates that eyewitnesses tend to identify the person on the line-up who most looks like the suspect, whether or not the actual suspect is in the line-up or not10

Given that the recent misidentification research has spawned much prescriptive material for police departmental policies and procedures, it follows that there is now a wealth of new information that can be incorporated within the first component of Perron’s The Component Method of Investigation. Specifically, the investigator should ascertain whether or not the following baseline procedures, which have been vetted by the US Department of Justice, were utilized by law enforcement in its identification processes: 11

· The individual line-up members or photos should be shown to the witness sequentially, rather than simultaneously;

· All stages of the identification process should be videotaped;

· Witnesses should be informed before any identification process that the actual suspect may not be in the line-up or photo array;

· Line-ups and photo spreads should be administered by an independent examiner who is not known to the witness and who has not been given the suspect’s identity;

· Witnesses should be asked to rate their certainty at every stage of the identification process.

Witness misidentification problems can also be unearthed during execution of components three and five of Perron’s The Component Method. Component three will yield key observation factors such as weather, degree of lighting, terrain, line of sight, obstructions, and distance. Component five will yield information regarding the witness’s statement congruence with the aforementioned crime scene variables documented by the investigator. A thorough witness interview (component five) will also aim to discover factors such as stress levels, potential intoxication, eyeglass wear, familiarity of observation towards members of other races (if relevant), and duration of the observation of the suspect.


Scheck and Neufeld report that police misconduct was a factor in 50% of DNA exonerations and that prosecutorial misconduct was a factor in 45%.12According to Gershman’s 1992 article entitled The New Prosecutors,13 the uncontrolled discretion of prosecutors’ facilitates – among other things – overcharging, vindictiveness, and plea bargaining abuses. Additionally, the police and prosecutors have numerous built-in advantages, including: full utilization of law enforcement resources, better ability to subpoena witnesses, moral suasion, and the ability to access additional funds.

Perhaps the most egregious ethical and legal violation, namely the nondisclosure of exculpatory evidence, represents the arena in which a well-trained and diligent defense investigator can make the most impact using the component method. In the majority of cases, this evidence relates to law enforcement and/or prosecutorial abuse of eyewitness accounts of the incident – including both errors of commission (e.g. perjured) and errors of omission (e.g. nondisclosure). Thus, starting with component one, the investigator should thoroughly examine all witness statements and testimony for inconsistencies – including those to the responding officers, those to detectives, those to prosecutors, and those to the grand jury. Another red flag that can be garnered from analysis of the statements and testimony is the evolution of an individual’s statements from the general to the specific, an inherently counter-intuitive process that oftentimes represents coaching on the part of the prosecution or of law enforcement. Errors of omission are also of critical importance in this review, so particular emphasis should be placed on those witnesses who may have made earlier statements to the police yet were not summoned to testify before the grand jury, with the inference being that their testimony would not be particularly congruent with prosecution theories of the case.

Components four and five can be utilized to pro-actively identify, locate, background, and interview all potential witnesses – both alibi and eyewitness, whether disclosed or undisclosed. The investigator should not be deterred by the hazy category of so-called “prosecution” witnesses – they are as fair game for the defense as for the prosecution. Their statements to the defense investigator should be thoroughly compared to existing statements and physical analysis of the crime scene. Their backgrounds should be checked exhaustively, with particular emphasis on character, past criminal activity, and potential deals cut with law enforcement or prosecutors. Any witnesses recently or currently incarcerated should therefore receive extra scrutiny, given the potential leverage that could be exerted over them. With respect to names provided by the defendant, each one should be checked out and then hopefully pyramided into other names by in-depth interviewing. In short, witnesses identified in discovery materials represent merely an excellent starting point in a thorough investigation.


From every corner, the wrongful conviction literature shouts out for more thorough and higher-caliber defense investigation. It can be viewed as nothing short of a call to arms for the industry. Without adequate investigation, a defense attorney is defending his client with little or no ammunition whereas the firepower of the prosecution side can oftentimes be enormous. As F. Lee Bailey states: “a good investigator is generally more valuable to a defendant’s case than a good lawyer.” Thorough schooling in and consistent application of The Component Method of Investigation will allow the investigator to maximize this value that is so central to the fair operation of our justice system.


(1) The Journal of Criminal Law and Criminology: 2005; volume 85, number two. Exonerations in the United States 1989 through 2003, by Samuel Gross, Kristen Jacoby, Daniel Matheson, Nicholas Montgomery, and Sujata Patil.

(2) The New York Times, April 19th 2004. Study Suspects Thousands of False Convictions, by Adam Liptak.

(3) Speech delivered to the Investigators Superconference August 24th, 2002. “Wrongful Convictions – Our Nation’s Disgrace”, by Grace E. Castle CLI.

(4) UNCOVERING REASONABLE DOUBT. The Component Method. Criminal Defense Investigation: 1998. Brandon Perron.

(5) UNCOVERING REASONABLE DOUBT. The Component Method. Criminal Defense Investigation: 1998. Brandon Perron.

(6) The Journal of Criminal Law and Criminology: 2005; volume 85, number two. Exonerations in the United States 1989 through 2003, by Samuel Gross, Kristen Jacoby, Daniel Matheson, Nicholas Montgomery, and Sujata Patil

(7) Working Paper presented at Andrews University – Berrien Springs, Michigan on May 2nd, 2001. How Mistaken and Perjured Eyewitness Identification Testimony Put 46 Innocent Americans on Death Row-An Analysis of Wrongful Convictions since restoration of the death penalty following Furman v. Georgia, by Rob Warden.

(8) Convicting the Innocent: 1932. Dr. Edwin Borchard

(9) Psychology Today, January 1996; page 48. The diva of disclosure, memory researcher Elizabeth Loftus, by Jill Neimark.

(10) Annual Review of Psychology: 2003; volume 54. Eyewitness Testimony, by Gary Wells and Elizabeth Olsen.

(11) Eyewitness Evidence: A Guide for Law Enforcement: 1999. The National Institute of Justice (DOJ).

(12) Actual Innocence: 2000. Barry Scheck and Peter Neufeld.

(13) University of Pittsburgh Law Review: 1992; volume 53. The New Prosecutors, by Bennett Gershman


The culmination and crystallization of an investigator’s body of work on a case is reflected in the written product to the attorney and in his testifying in open court (which Perron addresses this in component six). Thus, if superior oral and written communication skills are lacking, the gist of the investigative findings may never find their way into the public arena. Ultimately, this is the only factor that really ends up counting.