Forensic examination is a core feature in relation to legal cases and the court process. It is commonly used to bring in expert opinion on minute but significant details pertaining to a case relating to a trial (Smith & Bull, 2014). This expert opinion is often treated as defining in terms of its placement within the context of the case itself, with opinion and the process often overlooked. Essentially, the conclusion given by the expert or consensus by a number of experts is generally treated definitive. However, this notion has been largely criticised from particularly the psychological domain (Pozullo et al, 2015). It is true that forensic examiners may become exposed to a variety of contextual factors not pertaining to the direct details of the evidence, which in turn may vary or sway their conclusions about the evidence they are addressing (Smith & Bull, 2014). For instance, the nature of such factors as fingerprints, fibres, and tool marks may be taken as strong evidence of guilt, while other evidence to the contrary is not deemed as significant. While the role of the forensic expert is recognised from a more critical angle currently, the concept and arbitration of the forensic expert is still one decided by the legal rather than psychological domain (Smith & Bull, 2014). In psychology, expert forensic analysis is tasked in making skilled observations and conclusions that are consciously aware of the biases that the observer may have (APA, 2013). In this sense, a conclusion must be minimally compromised by bias and ambiguity is accepted in order to create a more reliable and accurate picture regarding evidence (APA, 2013). While this is beginning to bear fruit in a number of new approaches aimed at minimising biases, the notion of what should and should not be disclosed as evidence is becoming ever more salient an issue.
The concept of disclosure in a legal sense is used to distinguish the limited scope in which information regarding a case must be provided to the other party (Smith & Bull, 2014). For instance, the prosecution requires to disclose exculpating evidence to the defence to maintain an equal grasp upon how the case is going so that their case can fully represent the findings as they unfold (Smith & Bull, 2014). Forensic disclosure is similar in that it draws upon the same limited scope; a scope in which the expert must provide their findings to all parties as an otherwise impartial observer (Pozullo et al, 2015). However, this also includes the information that must be provided to the expert so that they may be able to examine and analyse the information in context (Smith & Bull, 2014). This means that any proposed changes to the way in which the forensic expert functions must be enacted through the process of disclosure, making disclosure a fundamental part of expert analysis, decision making and eventual outcome. For this assignment, an attempt is made to broaden and expand the scope of the process of disclosure to detail what can be made of the process of forensic disclosure. This will permit an examination of what information can and should be disclosed to the forensic expert as well as what can and should be disclosed from the forensic expert about the process of analysis and decision making. The emphasis is to contribute to the attempt to find the best possible approach so that they may do their job in the best and most impartial way. Although forensic disclosure in this sense is distinct from legal disclosure, it follows the same legal imperative.
To examine or re-examine the role of forensic disclosure in relation to forensic expert analysis it is necessary to draw out and upon the various mechanisms known to create problems that lead to inaccuracy (Neal & Grisso, 2014). This includes identifying many of the key factors that have been overlooked in relation to the role of the expert in relation to their decision making (Neal & Grisso, 2014). In this sense, it would be prudent to keep in mind the dominant conceptualisation of the forensic expert in the legal domain to see to what extent it masks and enables problems that lead to unreliable conclusions. The dominant factor here is the role that biases play. The extent that biases play in life are well established within the psychological and scientific domain (Neal & Grisso, 2014). For instance, political bias can sway the way we interpret the same set of information so that it accords to our already established political world view. However, the forensic expert is more likely to be aware of the majority of everyday biases, such as favouritism and other subjectivities, in relation to their role as a forensic expert (Pozullo et al, 2015). However, rather than their role ridding them of biases altogether, it can produce its own biases, such as the idea of not being biased. Indeed, this status defined bias could be manipulated across several features. Expert bias is a social bias the relates to the expert’s role in relation to the task they are charged with, in that they are expected, above all, to be the final say on a piece of information and ultimately contribute something definitive on the evidence in relation to the case (Neal & Grisso, 2014). This bias is based upon expectation, acting as a social rather than cognitive bias, known to be derived from and contribute to a strong sense of duty and authority (Neal & Grisso, 2014). The outcome of expert bias is to negate ambiguity regarding an interpretation of data and to suggest with confidence what has occurred.
The role of bias in relation to interpreting information is also a strong cognitive feature (Dror, 2018). This is due to an affliction to incorporate contextual information in relation to what is being observed and analysed, which can thus shape the findings of an otherwise scientific analysis (Dror, 2018). Indeed, this contextual information is what each legal representative argues in court in relation to the guilt and innocence of a subject and forms the shape of the ongoing case. However, in forensic science, the role of contextual factors pertaining to the case are seen as being superfluous to the forensic expert’s task, which is to determine and interpret the data scientifically and objectively without any partisanship (Neal & Grisso, 2014). This indifference and objectivity are problematic and can be seen in what Dror (2018) describes as extraneous information (Dror, 2018). Indeed, Dror (2018) goes on to state that extraneous factors can range across numerous domains including “from a suspect's ethnicity or criminal record to eyewitness identifications, confessions, and other lines of evidence—can potentially cause bias” (Dror, 2018, p.iii). It is biases of this kind contained within otherwise objective data that is the cause for concern and having such details disclosed has the potential to add layers of contextual information to the task at hand (Stoel et al, 2015). However, this is not to say that the biases exist in the data itself or in the extraneous world beyond the expert. Rather, the bias exists within both the expert’s mind and the process in which the expert interprets and makes decisions meaning that the information simply acts as a cognitive trigger to evoke often subconscious biases (Stoel et al, 2015). These may be simple social prejudices that are not perceived by the expert or more personalised favouritisms toward favouring a specific type of scientific methodology. Such extraneous variables may give rise to various conclusions that are frequently incorrect or overstated, thus bringing about an outcome within the court that is unsound.
One of the major consequences of biases caused by extraneous variables is that the process of science is misused, which can lead to a misleading trial in court. However, one of the key features is not only that irrelevant information can bias a particular aspect of an investigation, but that it can lead to what is termed a “bias cascade”, which is the effect of one component of an investigation leading on to another across the entire case (Dror, 2018, p.i). The notion of the bias cascade comes from the psychological domain and the phenomena known as the availability cascade, in which a notion that may lead to a simple explanation of a more complex and often contradictory phenomena is favoured (Dror, 2018). Once adopted across a body of people, the cascade effect occurs as it converts all other pieces of information, some of which may be contradictory and interprets them within the context of the original explanation. This may lead to compliance from a number of experts, thus establishing further a contextual narrative from which analysis is shaped and conclusions are drawn. For the forensic expert, knowing the apparent way in which the case is going may act as vantage point from which they interpret the data, adding to the cascade effect (Dror, 2015). When matched with the cascade bias and availability cascade phenomena, biases such as expert bias may lead to an unwavering confidence in an interpretation that simply sides with the dominantly perceived outcome of the case. The field of legal psychology offers a range of phenomena that occurs in the relation to bias (APA, 2013). Indeed, the process of sensual data involved in a representation is often distinct from the higher forms of procedural interpretation, which pertain to cultural, contextual and historical features (APA, 2013). The difficulty for the forensic expert in this scenario is that they are assigned within the legal context to offer an opinion on one specific element without regard to the contextual factors, which in the legal domain would be the case, dominant theories relating to the epistemological study of the specific subject matter, and how other factors may impact on the findings they make.
Confirmation bias is another aspect that can lead to error and therefore another area in which the forensic expert should be tasked with disclosure (Dror & Stoel, 2014). By finding the evidence leading towards a certain conclusion, it could be that the opinion of the analyst is strengthened due to findings of a similar or arbitrary nature. For example, finger prints matching a suspect may confirm the person’s guilt, thus resulting in the forensic scientist strengthening his opinion of that evidence as indicative of the situation (Dror & Stoel, 2014). In short, one form of evidence may be favoured over another, as it points to the guilt of the culprit, which in turn validates the evidence as correct. However, the guilt of the culprit is inconsequential to the evidence and what it says and has no bearing on whether the evidence is right or wrong. Conversely, DNA tests may prove that the finger prints are unreliable s they identify a different culprit or reveal that they were not the owner of the finger prints, meaning that perhaps another area of the case has been lacking in its clarity (Dror & Stoel, 2014). Thus, it is the fact that the finger prints point to the presumed guilty party that determined the validity of the conclusion and not the evidence itself. In relation to disclosure, confirmation bias underlies a need that contradicts contextual bias in that it indicates that a large proportion of the case’s history requires disclosure alongside the evidence. Otherwise, it may be that the forensic analyst is using whatever evidence points to a conclusion rather than incorporating collection of evidence that may have no bearing, is ambiguous or points away from the case. Again, this reinforces the case for the analyst to detail not only their findings, but their entire process and how they came to whatever conclusion they did. In doing so, confirmation bias is then highlighted so that the expert may overcome their reliance on one set idea or approach thus helping to partially eliminate the onset of the cascade effect. This is illustrated by Dror (2018) who states that “whereby the bias increases in strength and momentum as different components of an investigation influence one another, bias also arises when forensic experts work backward: Rather than having the evidence drive the forensic decision-making process, experts work from the target suspect to the evidence” (Dror, 2018, p.ii). However, while allowing for ambiguity may be regarded as progress towards the elimination of biases, there is a danger that giving a non-conclusive answer may be driven by the wrong motivation. For instance, Dror & Langenburg (2018) state that deliberating to a verdict of inconclusive should not be considered “deciding not to decide,” but instead should be viewed as a decision in itself. It should be understood as a decision of certainty in that the quantity and quality of the information provided was not sufficient enough to draw a conclusion regarding the source of evidence, whether that be finger prints, clothing from the scene of the crime or the reliability of eye witness testimony (Dror & Langenburg, 2018).
The reliability of case-based factors that may impinge on a decision making are commonly given in research as eye-witness testimony and finger prints (Fischer et al, 2009). Eye witness testimony itself is not reliable (Fisher et al, 2009). However, the impact of identification can begin to amount a body of suspicion and evidence against a certain party and generate a narrativized impression of what had occurred. Of course, this is what both prosecution and defence build their cases on to sway the evidence in a certain direction. However, when there is a clear notion of an event that took place and the question is deducing what happened and essentially who is responsible for it, the emphasis falls upon the most likely of scenarios. This ontological stance is crucial as to why although evidence such as eye witness is widely inaccurate, it can form the basis for a cascade effect, which then incorporates the confirmation bias effect (Dror & Stoel, 2014). In itself, the confirmation bias is commonly observed on cognitive recall when people give accounts, accepting the details of others in place of the vague memories they may have. Another area of sway unrelated to the forensic experts’ line of inquiry is pressure from authority (Dror & Stoel, 2014). This commonly includes police officer accounts, which may have derived a false confession (APA, 2013). Ultimately, disclosure of the reliability of this information is crucial to establishing a context in which the expert can arrive at impartial and objective conclusions regarding evidence and what should be and should not be considered evidence.
A way of seeking to avoid biases head on and to ensure an impartial transition of transparent information has fallen upon the case manager (Found & Ganas, 2013). The case manager is currently used as an impartial and professional mediator between parties that secures the impartiality of all involved with the forensic examination of evidence pertaining to a case (Found & Ganas, 2013). The role of case manager has been enshrined by law in the UK and is continuing to grow considering research and feedback from the psychological domain. From a legal standpoint, the role includes communicating with both internal and external stakeholders to ensure that the key requirements and priorities involved in a case are fully understood (Found & Ganas, 2013). This includes the actioning of any matter or decision in accordance with the constitutes of normal disclosure, which includes the attendance at any major crime strategy meetings, offering specialist advice in any context, and giving guidance in respect of the effectiveness of the forensic examinations that have or are to be taken place (Alison, 2013). Heavily involved in the forensic element of disclosure and process management, submissions of forensic procedures and support to produce forensic strategies form the basis of their role (Found & Ganas, 2013). However, the strength of their involvement has not yet been fully investigated and they are not yet fully embedded (Murrie et al, 2013). While the adoption of case managers had been largely ignored, another problematic factor involved in adopting countermeasure approaches of this kind is that many of the forensic experts do themselves have a blind spot for biases (Alison, 2013). Ultimately, they cannot see the implicit biases that pertain to their role as expert and subsequently tend to deny that they exist at all. Forensic experts are known to present their decisions in court with a great deal of assuredness and take the court's acceptance of their findings as confirmation of their findings (Cutler & Kovera, 2011). Indeed, Dror (2018) simply states that “acknowledging that bias can influence forensic science experts would be a substantial step toward implementing countermeasures that could greatly improve forensic evidence and the fair administration of justice” (Dror, 2018, p.3).
Unravelling the question of what should and shouldn’t be disclosed to forensic experts is clearly an issue for the case manager (Zapf & Dror, 2017). Similarly, the best way for the manager to establish the outcome of this question is in relation to the various biases that abound. A certain level of information regarding the case will be known by the expert, but matters relating to how the evidence was found and how it relates to the case is of maximum importance to be guarded (Found & Ganas, 2013). Other methods include explaining to the expert what the precise details of the evidence. However, this may have damaging side effects as the manager may be consciously or unconsciously veering the details towards a perception of the case owing to their knowledge of how it is unfolding and other contextual details (Zapf & Dror, 2017). In this scenario, the best way to approach disclosure is to limit the details of the process solely to the expert and place it within the context of what can be verified and proven. Highlighting the acceptability of ambiguity is one way in which the role of expert and extraneous pressure caused by job role and social expectation can be alleviated for the forensic examiner. Another way of dealing with biases is in the use of training. Indeed, Zapf et al (2018) point out that experts who receive training about the prevalence and nature of biases in the process of evaluation are more likely to acknowledge their own social and cognitive bias as a cause for concern. This contrasts with those who base their status on experience, who are less likely to acknowledge cognitive bias as a problem in forensic evaluations (Zapf et al, 2018). The researchers concluded that training efforts must highlight bias ‘blind spots’ as well as techniques used to reduce bias, stating also that “policies and procedural guidance should be developed in regard to best cognitive practices in forensic evaluations” (Zapf et al, 2018, p.iv).
There have been proposed several ways to deal with this phenomenon from a theoretical and epistemological view to a scientific and ontological view. The approach adopted by most revolves around the notion of the process of expert forensic analysis and around the transparency of that analysis. In essence, the former looks to change the way the analysis is performed and addressed, while the latter tends to look upon how this relates to the process of forensic evidence and the case in question (Murrie et al, 2013). The use of case managers has emerged, at least theoretically, as a way to assist in ridding the manufacture of many of the biases associated with the disclosure of forensic evidence. By using case managers, extraneous factors pertaining to any one case can be removed before being presented to the expert for analysis (Found & Ganus, 2013). One of the skills used by the case manager is by departmentalising the process in which evidence is provided. For instance, they may ensure that the person collecting the data for analysis is not the same person as the one analysing it, while also ensuring that the information provided in each instance is made clear and relevant to the case itself (Murrie et al, 2013). This can then be fed back to the parties involved with the case equally to accord with the integral notion of disclosure. Essentially, while being non-partisan, the case manager’s role is simply to ensure that the extraneous information and information regarding the case is acknowledged while it is not transmitted to the expert and operator at each stage of its process. Further, Kassin et al (2016) note that the role that contextual and historical information plays in the role of decision making is crucial to establishing the reliability of certain evidence and the context in which it is produced. Indeed, the HMRC have implemented an approach that has determined that disclosure must include all unused material as a key component of the investigation to undermine a reliance on certain information and in turn confirmation bias (Cutler & Kovera, 2011). In this sense, every item must be considered relevant and requires review to establish whether it may undermine the prosecution or assist the defence.
As we have established thus far, there are any number of biases that can and do exist throughout the plethora of instances that relate to a legal case. From expert bias to confirmation bias, these features must be acknowledged within the context of disclosure. When information is presented to the expert, they must ensure that their role as expert does not pressure them to arrive at any conclusion or to consider their role as expert in relation to their decision making (Hamirani et al, 2017). Expectations based upon authorities, such as confession-based evidence, must be disregarded as it does not relate to the task being approached by the expert. However, there may be a willingness to approach the subject matter contextually in relation to the culprit’s guilt or innocence due to a perception made clear in the case (Nakhaeizadeh et al, 2017). Cognitive biases of this kind must be approached from a vantage point, which gives the case manager the emphasis of being an arbitrator of what should and should not be disclosed to the forensic specialist in legal cases. It is perhaps the immensity of this somewhat complex role and the number of departments that may be required in high level crime cases involving CSI departments and such that the case manager role can be seen split into different jobs (Nakhaeizadeh et al, 2017). Context information management is another related role that can be applied to new approaches to case management such as the linear sequential unmasking approach, which seeks to unveil suspects and information as it progresses. In this sense, the LSU discloses information after assessing a request for further and essential information regarding a case. In this sense, they are closely linked to the CSI group or forensic specialist in an ongoing case. Indeed, Nakhaeizadeh et al, (2017) stipulate that the CSI should convey evidence with only the relevant contextual information required as without these measures “irrelevant information and bias can cascade from one stage to another” (Nakhaeizadeh et al, 2017, p.iii). The attempt here is clearly one of bridging the gap between a reliance on confirmation bias’s affliction to contextual information and expert bias’s aversion to it.
One of the methods currently being developed to compensate for contextual bias is the use of the filler-based sample model. The ﬁller control method associated with the filler sample model contrasts with the standard approach of using a sample from the crime scene and a sample from the suspect (Hamirani et al, 2017). This presents the forensic expert with a minimum of three samples. These are from the crime scene, from the suspect and from an innocent scenario, the latter known as the filler sample. The analyst is then charged with the task of determining the scientific validity of the suspect and crime scenarios in relation to other possibilities (Dror, 2015). The filler-controlled method has four key requirements. They are to estimate error rates for both a technique used, and the individual analyst concerned, to have psychological and sociological experts assist in the calibration of forensic analysis, to quickly remove fraudulent analysts and poor science, and to protect the expert and the case from contextual and extraneous influences (Hamirani et al, 2017). Owing to the strength of validity matched against the prevalence and appropriateness of findings from the filler samples, this approach would assist in detailing the reliability of the evidence of both suspect and crime scene (Stoel et al, 2015). Further, it would provide comparative findings to and from the expert without contextual variables owing to the given context implied in the task, while also allowing for more information to be disclosed on the reliability of both the expert and the method they used to extrapolate findings and deliberate conclusions (Kassim et al, 2013). Indeed, Zapf et al (2018) note that as most evaluators view their willpower as a means to reduce bias, they cannot be firmly trusted on the basis of expert status alone. Furthermore, using the process of consensus is also ineffective as most evaluators acknowledge bias in their peers’ judgments than in their own (Zapf et al, 2018). However, by implementing a filler sample model, evaluators can then see for themselves the accuracy and inaccuracy of their findings and how their bias may have impacted on the findings and their subsequent conclusion. As a result, the need to rely on their own status as an expert or to conform to consensus is alleviated, leaving the findings of the analysis in relation to the filler sample to dictate their ability. Ultimately, this acts in bridging another gap by revealing more domains in which experts lack the necessary data to address fundamental aspects of their performance, such as reliability and bias among experts (Dror & Murrie, 2018). Ultimately, it is by understanding these strengths and weaknesses in the framework of forensic assessment that research findings should continue to guide the testimony of forensic psychologists and future research in forensic assessment (Dror & Murrie, 2018).
While forensic evidence still plays a crucial role in relation to legal proceedings and court cases aiding the better administration of justice, the role of the forensic examiner and the process of forensic examination requires scrutiny. It is clear that the use of forensic evidence is a powerful approach that assists in the conviction of the guilty and can attribute to the avoidance of the wrongful conviction of innocent parties. However, flaws exist in forensic evidence, which are increasingly becoming apparent in the field of forensic analysis. Long understood in the psychological domain, assessments of forensic science have relied too heavily on the data involved placing unscrutinised emphasis upon the exactitude of the underlying science involved. This places the science and its laws in isolation without addressing the integral process in which forensic experts evaluate, interpret and determine the meaning of the data provided in evidence. Thus, the humanistic factors pertaining to cognitive, sensual, social and political features of an expert are often overlooked in place of the examiner as a font of knowledge.
The use of better forms of disclosure ultimately corresponds with transparency regarding the entire process involved in giving expert testimony. Just as with legal disclosure, it is important that the process of forensic disclosure does not seek to hide behind notions of expertise or contextual evidence. All information deemed important and relevant must be offered, even if it may strengthen an opposing view. However, it is also crucial that contextual and extraneous information is not disclosed to the forensic expert as this can bias their findings. Furthermore, this must be arbitrated so that they are given the information that is required in relation to the evidence. Similarly, there should not be an overreliance on the expert and their peers in relation to their conclusions, but rather, have an accountable process in which their findings can be evaluated by a case manager or third party. Currently, case managers and the use of filler samples currently offer the best means to assist in delivering this, while alleviating problematic biases.
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