Minimising bias in the forensic evaluation of suspicious paediatric injury

Abstract

In the rules of evidence in all legal jurisdictions, medical experts are required to maintain objectivity when providing opinions. When interpreting medical evidence, doctors must recognise, acknowledge and manage uncertainties to ensure their evidence is reliable to legal decision-makers. Even in the forensic sciences such as DNA analysis, implicit bias has been shown to influence how results are interpreted from cognitive and contextual biases unconsciously operating. In cases involving allegations of child abuse there has been significant exposure in the media, popular magazines, legal journals and in the published medical literature debating the reliability of medical evidence given in these proceedings. In these cases judges have historically been critical of experts they perceived had sacrificed objectivity for advocacy by having an investment in a 'side'. This paper firstly discusses the issue of bias then describes types of cognitive biases identified from psychological research applied to forensic evidence including adversarial bias, context bias, confirmation bias and explains how terminology can influence the communication of opinion. It follows with previously published guidelines of how to reduce the risk of bias compromising objectivity in forensic practices then concludes with my own recommendations of practices that can be used by child protection paediatricians and within an organisation when conducting forensic evaluations of suspicious childhood injury to improve objectivity in formulation of opinion evidence.

Thinking fast and slow in the evaluation of injury plausibility in child protection

“…Adversarial biases arise when experts either consciously or subconsciously align their thinking with the ‘side’ that has sought their opinion. Experts can be motivated by financial rewards, prestige or derived from belief in a ‘cause’ 13 . As an example, this can arise when experts fail to include child abuse in their differential (e.g.…”

“…This has been referred to as ‘denialism in child abuse’, whereby pseudo‐scientific hypotheses are posited as valid conditions to achieve a coherent argument in line with their preferred narrative 14–16 . These views are typically driven by emotion which can operate to produce bias in either direction (to invoke or discount abuse), by producing the same conclusion in all submitted cases, regardless of the truth or analysis of the individual facts 13 …”

“…Experts can be motivated by financial rewards, prestige or derived from belief in a 'cause'. 13 As an example, this can arise when experts fail to include child abuse in their differential (e.g. defence-only experts) due to sole reliance of system I thinking without shifting into systems II analysis.…”

“…[14][15][16] These views are typically driven by emotion which can operate to produce bias in either direction (to invoke or discount abuse), by producing the same conclusion in all submitted cases, regardless of the truth or analysis of the individual facts. 13…”

The developing significance of context and function: Neuroscience and law

“…Another aspect of confirmation basis may derive from political or social beliefs that people who are arrested are guilty of something, even if not this particular crime, or from the assumption that people of a certain racial or economic status are more likely to commit crimes (Ghandnoosh, ; Homant & Kennedy, ; Skellern, ; Stanley, Phelps, & Banaji, ).These factors may influence an evaluator to ask specific offense or criminal history questions without seeking contextual information. For instance, diagnosis of ASPD requires a juvenile onset and evidence that a conduct disorder existed prior to age 15, a pattern of behavior over time, and is not to be based solely on adult criminal conduct (APA, ).…”