Expectancy Effects in Forensic Evidence Handling

1. Expectancy Effects in Forensic Evidence Handling * Exploring a model of expectation transfer V. Springer -- University of Nevada, Reno -- April 3, 2007

2. The Impossibility of Expecting the Unexpected: Identity, Exchange, and a General Model of Transferred Expectations in Forensic Evidence Handling Expectancy effects in evidence handling pose a serious threat to the validity of analyses conducted by forensic examiners. This critical compromise creates an impasse regarding key assumptions of law regarding the admissibility of scientific evidence and testimony. The history of rules of law governing the use of scientific evidence are detailed, followed by a review of experimenter effects, observer effects, and a model that integrates them into a general theory of transferred expectations. The general model posits that expectancy effects are communicated from observer to target (experimenter effect), and then are manifested between target and object (observer effect), when the analysis of an object impacts both the target and the original observer.

3. OUTLINE OF PRESENTATION Assumptions of Law The Forensic Context The Forensic Lab Environment Expectancy in the Courts: Bias at the Gates Expectancy Effects Foundations of Transferred Expectations Distinction of Observer Effects Persistence of Experimenter Effects The General Model of Transferred Expectations Expectancy Transfer and Forensic Analysis The Effect of Information on Expectancy Effects Future Research

4. Assumptions of Law The Importance of Forensic EvidenceResearchers have found that forensic evidence appears to increase rates of arrest, charging and conviction (Peterson, Ryan, Houlden & Mihajlovic, 1986). The importance of forensic science and crime laboratories and their intrinsic value to police and legal experts has never been questioned (Peterson, Mihajlovic & Gilliland, 1984). Evidence and Expert Testimony Scientific evidence is thought to be intrinsically more reliable than other kinds of evidence, such as eyewitness accounts and statements from defendants, because of its physical basis (Peterson, Ryan, Houlden & Mihajlovic, 1986). Critical Evidentiary Standards 1923-1993: the Frye rule (general acceptance) 1993: Daubert v. Merrill-Dow Pharmaceutical Justice Blackmun set the benchmark for the judicial review, from which three fundamental criteria emerged--falsifiability, peer review, and known error rate--as standards of evidentiary reliability. This opinion demands that evidence be proven through the crucible of "submission to the scrutiny of the scientific community" in order establish the evidence as the product of "good science" (Daubert v. Merrell Dow Pharmaceuticals, 1993). In conjunction with General Electric Company v. Joiner (1997)and Kumho Tire Company v. Carmichael (1999), the collectively named Daubert Trilogy is currently the gold standard for the admission of scientific evidence and expert testimony.

5. The Forensic Context The Role of the Forensic Examiner According to the Daubert criteria, the goal of the scientist is not to make the case for the prosecution or the defense, but rather to present not just science, but "good science." A forensic scientist is not a detective. The reason the results of forensic analysis are admissible "is not because forensic scientists are better at drawing conclusions about the meaning of normal relevant evidentiary information than detectives or jurors; it is because the law has accepted that, as to a defined area of specialized knowledge or skill, the products of their practice are better than the jury could do alone” (Risinger, Sake, Thompson & Rosenthal, 2002, pp 28). With these safeguards in place for the admission of evidence, it seems fitting that there be a natural analog regarding the preparation of evidence before it reaches the courtroom. A deep-seated assumption under law involves the presumed lack of subjective interpretation or personal motivations of the forensic examiner. Forensic scientific evidence is given unique and weighted importance because of the presupposed impartiality and objectivity of the experts who examine and interprets the evidence (Peterson, Ryan, Houlden & Mihajlovic, 1986). If this objective handling presumption is brought into question, and in fact shown to be false, the Daubert criteria may not be enough to keep "junk science" out of the courtroom.

6. The Forensic Context When Forensic Objectivity Fails Unfortunately, the impetus for definitive research in the field of forensic science has only been conducted after questions have been raised about the accuracy and reliability of its procedures, usually in court (Kelly & Wearne, 1998). The Madrid Train Bombing (2004) In collaboration with Spanish authorities, the FBI identified latent fingerprints found on a plastic bag that was linked to the bombing. The FBI identified a suspect by means of fingerprint analysis, a lawyer from Oregon named Brandon Mayfield who had ties with the Muslim community, and was ultimately proven wrong in this identification (The Associated Press, 2004). The findings of the panel that investigated the false link to Mayfield highlighted a critical complaint about the general field of forensic science. The evidence that is assumed to be both scientific and unbiased in order to be admitted into American courts often fails to meet either of those standards (McRoberts & Possley, 2004). Stacey Report: "The power of the IAFIS match, coupled with the inherent pressure of working an extremely high-profile case, was thought to have influenced the initial examiner's judgement and subsequent examination. This influence is recognized as confirmation bias (or context effect) and describes the mind-set in which the expectations with which people approach a task of observation will affect their perceptions and interpretations of what they observe" (pp 6-7, italics added).

7. The Forensic Context Expectancy in the Courtroom: Bias at the Gates According to Koppl (in press), one might argue that good lawyering is the cure for bad forensics. United States of America v. Darryl Green In 2005, United States of America v. Darryl Green involved defense Daubert challenges, including one specific to the prosecution's firearms expert citing "observer bias and lack of blind testing." United States of America v. Rudy Frabizio The "peer review" process critical to the Daubert guidelines, was violated by a lack of independent review. In fact, Musheno's coworker evaluated the images in question "contemporaneously with Musheno's checklist and report, fully aware of Musheno's conclusions." Expectancy effect question the methodology by which a particular result was garnered on a fundamental level. If the presence of known causes of expectancy effects are present in the process of forensic analysis, it is logically impossible to say with any kind of surety whether or not the results of these tainted analyses are only a reflection of these expectations rather than scientific fact. "This would seem the very definition of ‘unreliability.’” (Risinger, Sake, Thompson & Rosenthal, 2002, pp 54).

8. Foundations of Transferred Expectations Distinction of Observer Effects vs. Experimenter Effects Experimenter effects (Rosenthal, 1950s) Involve experimenter expectations about the outcome of an experiment or subject behavior and has the potential to influence the experimental results (Langlois & Prestholdt, 1977). What should be pointed out here is that experimenter effects do not involve an error in perception. The experimenter, in fact, sees a real manifestation of the behavior of interest in the subject. This behavior, however, was instigated by the experimenter, and accordingly is not reflective of the true state of reality. Observer effects The behavior of the subject does not change, but rather the experimenter "makes errors of apprehension because [he] does not see things as they are, but rather as he thinks they ought to be" (Langlois & Presthold, 1977, pp. 134). OTHER EXPECTANCY (related) EFFECTS: Pygmalion Effect, Hawthorne Effect, Subject-Expectancy (Placebo), Reflexivity (forerunner of Self-fulfilling Prophecy), and (generally speaking) Demand Characteristics.

9. Expectancy Effects Connection to Self-Fulfilling Prophecy According to Merton, "The self-fulfilling prophecy is, in the beginning, a false definition of the situation [which evokes] a new behavior which makes the originally false conceptions come true" (1948). The inherent danger of a self-fulfilling prophecy is evident in its ability to make an objectively false situation appear subjectively true. Merton's definition describes an interaction "in which one individual imposes an expectancy on a target individual in such a way as to make the second individual behave in a fashion which confirms the expectancy" (Darley & Fazio, 1980, pp. 869). In this way, the expectation is sustained by tainted evidence of its own validity. One of the fundamental principles of modern psychological study of expectancy effects is that the desires and expectations that people possess affect their perceptions, understandings, and interpretations of what they observe. The results of any scientific observation, then, depends at least partly upon the subjective state of the observer as well as the object, or evidence, being observed (Risinger, Saks, Thompson & Rosenthal, 2002).

10. Expectancy Effects … ok, great -- so what about transfer? Persistence of Experimenter Effects Whether expectations are created by or imposed on the individual, the altered exchanges that they cause have been found to carry through to later social interactions (Fazio, Effrein, & Falender, 1981). In experimental settings, it has been shown that an experimenter's expectations affect subject behavior while in the presence of the experimenter and without the experimenter during a subsequent interaction with a stranger. Fazio, Effrein, and Falender (1981) found experimenter effects persisted, even when the subject left the experimenter's presence and entered a new and different social interaction. This preservation and continued manifestation of expectations across situations, is crucial for the establishment of the continuum of expectations that links experimenter and observer effects.

11. General Model of Transferred Expectations The general model of transferred expectations proposes that expectations are passed from experimenter, or observer, to target and then consequently manifested in the target's perception of an object, particularly when the target's subsequent analysis of the object impacts both the target and the original observer. The general model expands on the interaction sequence by adding the possibility of subsequent observer effects after an experimenter effect has already taken place. • Social Interaction Sequence • “Simple social interaction” • involves the following features: • (a) a perceiver's formation of an • expectation about a target person, • (b) his or her behavior congruent with the expectancy, • (c) the target's interpretation of this behavior, • (d) the target's response • (e) the perceiver's interpretation of his or her own response • (Darley & Fazio, 1980, pp. 867).

12. General Model of Transferred Expectations The General Model of Transferred Expectations 1) E  T The observer interacts with target. 2) E(e)  T The observer forms and communicates expectation. 3)E(e) T(e) The target perceives and internalizes expectation. 4) T(e)  O Target carries out analysis of an object. 5) O(e)  E(e) The object meets the original observer's expectation. 6) E(e)  T, O Experimenter expectation for target, object reinforced. In a simplified linear fashion: E(e)  T  T(e)  O  O(e)  E(e)

13. General Model of Transferred Expectations

14. Expectation Transfer and Forensic Analysis Examiners as “Targets” In a number of ways, the crime laboratory can be seen as analogous to an experiment, where the police investigators in the lab are the experimenters (or observers) and the individual forensic examiners are the subjects (or targets) of the experiment (Risinger, Saks, Thompson & Rosenthal, 2002). Accordingly, “From this perspective, the beliefs and expectancies of superiors, coworkers, and external personnel are manifest in their behavior toward the forensic scientist ‘subject,’ in turn affecting the behavior of those ‘subjects’--their observations, recordings, computations, and interpretations--not to mention the additional impact role and conformity might have.” (Risinger, Saks, Thompson & Rosenthal, 2002, pp. 21). Law Enforcement and Other Agencies as “Observers” In terms of the general model of transferred expectations, if the forensic examiner occupies the position of “target,” then, consequently, other associated individuals must act as the observers that impart expectations upon the examiners. Law enforcement and other governing officials are strategically placed at the beginning of a cycle that reinforces itself through the results that it, in fact, induces. Reinforcing “transfer” cycles like the one presented here may be endemic to organizational settings This seems like a questionable fellow …UNLESS

15. Expectation Transfer and Forensic Analysis Examiners as “Targets” In a number of ways, the crime laboratory can be seen as analogous to an experiment, where the police investigators in the lab are the experimenters (or observers) and the individual forensic examiners are the subjects (or targets) of the experiment (Risinger, Saks, Thompson & Rosenthal, 2002). Accordingly, “From this perspective, the beliefs and expectancies of superiors, coworkers, and external personnel are manifest in their behavior toward the forensic scientist ‘subject,’ in turn affecting the behavior of those ‘subjects’--their observations, recordings, computations, and interpretations--not to mention the additional impact role and conformity might have.” (Risinger, Saks, Thompson & Rosenthal, 2002, pp. 21). Law Enforcement and Other Agencies as “Observers” In terms of the general model of transferred expectations, if the forensic examiner occupies the position of “target,” then, consequently, other associated individuals must act as the observers that impart expectations upon the examiners. Law enforcement and other governing officials are strategically placed at the beginning of a cycle that reinforces itself through the results that it, in fact, induces. He’s secretly Sherlock Holmes

16. Concluding Comments on Expectations The Effect of Information on Expectancy Effects “[Subjects] who were aware of the problem of [experimenter] bias were apparently able to suppress this set and exhibited essentially no bias in either the experimental and control condition” (Langlois & Presthold, 1977, pp. 139). This finding suggests that the cycle posited in the general model of transferred expectations is not impervious to negating factors. The cycle can be broken, and instruction on the true impact of expectations appears to be the key to the elimination of the effect. Further research into the multitude of causes and reinforcing factors of expectancy effects, particularly in forensic science, and the subsequent education of high risk professions stands as one practical and attainable solution to the problem of expectancy effects in evidence handling. Future Research In terms of the proposed general model of transferred expectations should be tested against traditional isolated experimenter and observer effects. These individual effects, having being treated as separate events by past studies, need to be compared to the results the proposed full version of the expectancy paradigm (E to T to O sequence) as proposed by the general model. If the results reflect similarities between the biasing power of the separate effects and the integrated model, it can be inferred, or at least it suggests, that there is some validity to the transfer model. If an expectation carried by an observer, communicated to a target, and manifested through subsequent object analysis occurs at the same magnitude as the traditional simple observer effect, then there is some credibility that the target has, indeed, transferred the expectation and fulfilled the experimenter’s prophecy.