Contextual information management: An example of independent-checking in the review of laboratory-based bloodstain pattern analysis

A review of quality procedures in the UK forensic sciences: What can the field of digital forensics learn?

“…A repeat blood search is carried out when blood pattern analysis is required because any missed bloodstains may have an effect on the interpretation of the pattern. A number of providers follow the blind peer review process as outlined in Osborne and Taylor (2018). Thus meaning that before any stain is sampled, an independent analysis of evidence is carried out, but in the absence of any contextual information or the original examiner's notes or interpretation/s.…”

How Cross‐Examination on Subjectivity and Bias Affects Jurors’ Evaluations of Forensic Science Evidence

“…Forensic scientists can greatly reduce or even eliminate the potential for contextual bias from Level 3 information by adopting context management procedures that shield them from exposure to contextual information that is irrelevant to their scientific judgment . For example, some laboratories make use of a “case manager” who intervenes between laboratory examiners and criminal investigators . The case manager works with investigators to determine what evidence needs to be examined and then passes evidentiary items along to examiners for examination, testing, and comparison.…”

The forensic disclosure model: What should be disclosed to, and by, forensic experts?

“…(e.g., Saks et al, 2003;Kassin et al, 2013;Mattijssen et al, 2016;Osborne and Taylor, 2018) Base Rate Almost always verifications are made for positive identifications (e.g., a fingermark match) so that over time the verifier could develop cognitive expectations (a 'base-rate'). (Dror, 2013;Stevenage and Bennett, 2017) Blind verification where the verifier does not know the judgement and decision-making of the examiner in advance, and where the verifier examines all decisions (not only positive identifications).…”

“…One approach for controlling the task-irrelevant biasing information that a forensic expert is exposed to when making decisions could potentially be achieved by incorporating a context (information) manager into the forensic reconstruction process (Risinger et al, 2002;Saks et al, 2003;Kassin et al, 2013;Dror, 2013). A role of this nature controls who gets what information and when, and it has been successfully used to control contextual information in handwriting analysis (Found and Ganas, 2013), firearms examination (Mattijssen et al, 2016), and in bloodstain pattern analysis (Osborne and Taylor, 2018). There is a case to be made that 'gate keepers' (such as case managers) should be the main point of contact with access to the contextual information pertinent to a case so that they are able to remove what they determine as task-irrelevant information (e.g., Saks et al, 2003;Found and Ganas, 2013;Kassin et al, 2013;Mattijssen et al, 2016) (Table 1).…”

“…In addition, the verifier does not know the judgement of the examiner during blind verifications (Kassin et al, 2013;Stevenage and Bennett, 2017). In this way the verifier works in an environment as free as possible from 'cognitive contamination' and does not know what they are verifying in a given situation (e.g., Osborne and Taylor, 2018). This is critical to fight base rate bias, as when only positive identifications are verified, or if the verifier knows what decision they are verifying, these create a base rate expectation and bias in that the original identification decisions will be verified.…”