Formulation and communication of evaluative forensic science expert opinion—A GHEP-ISFG contribution to the establishment of standards

Forensic DNA phenotyping and its politics of legitimation and contestation: Views of forensic geneticists in Europe

Forensic DNA Phenotyping (FDP) is a set of techniques that aim to infer externally visible characteristics in humans - such as eye, hair and skin color - and biogeographical ancestry of an unknown person, based on biological material. FDP has been applied in various jurisdictions in a limited number of high-profile cases to provide intelligence for criminal investigations. There are on-going controversies about the reliability and validity of FDP, which come together with debates about the ethical challenges emerging from the use of this technology in the criminal justice system. Our study explores how, in the context of complex politics of legitimation of and contestation over the use of FDP, forensic geneticists in Europe perceive this technology's potential applications, utility and risks. Forensic geneticists perform several forms of discursive boundary work, making distinctions between science and the criminal justice system, experts and non-experts, and good and bad science. Such forms of boundary work reconstruct the complex positioning vis-à-vis legal and scientific realities. In particular, while mobilizing interest in FDP, forensic geneticists simultaneously carve out notions of risk, accountability and scientific conduct that perform distance from FDP' implications in the criminal justice system.

Ethics as Lived Practice. Anticipatory Capacity and Ethical Decision-Making in Forensic Genetics

Greater scrutiny and demands for innovation and increased productivity place pressures on scientists. Forensic genetics is advancing at a rapid pace but can only do so responsibly, usefully, and acceptably within ethical and legal boundaries. We argue that such boundaries require that forensic scientists embrace 'ethics as lived practice'. As a starting point, we critically discuss 'thin' ethics in forensic genetics, which lead to a myopic focus on procedures, and to seeing 'privacy' as the sole ethical concern and technology as a mere tool. To overcome 'thin' ethics in forensic genetics, we instead propose understanding ethics as an intrinsic part of the lived practice of a scientist. Therefore, we explore, within the context of three case studies of emerging forensic genetics technologies, ethical aspects of decision-making in forensic genetics research and in technology use. We discuss the creation, curation, and use of databases, and the need to engage with societal and policing contexts of forensic practice. We argue that open communication is a vital ethical aspect. Adoption of 'ethics as lived practice' supports the development of anticipatory capacity-empowering scientists to understand, and act within ethical and legal boundaries, incorporating the operational and societal impacts of their daily decisions, and making visible ethical decision making in scientific practice.

Key individuals for discerning pedigrees belonging to the same autosomal kinship class

The existence of pedigrees belonging to the same kinship class (i.e. indistinguishable through independent markers) is well known in the forensic community, and theoretical frameworks for autosomal and X-chromosomal markers were already developed for a pair of individuals. Nevertheless, studies for the cases where a greater number of individuals is available for testing are still lacking. With this work, we intend to pave the way for a theoretical and general framework, identifying the individuals/relatives that should be chosen to distinguish autosomal analyses between such pedigrees. In this work we identify the individuals/relatives that are non-informative for calculations (the pedigrees under discussion remaining indistinguishable independently of their genetic profile), as well as those that will likely be very informative, influencing the statistical outcome. For example, given the respective genotypes, to compare the likelihoods of the father of the individual B to be: (a.) the father, or (b.) a full-brother, of the individual A, the hypotheses H₁: "The individual A is paternal half-sibling of the individual B", and H₀: "The individual A is paternal uncle/aunt of the individual B" are considered. It is proved that considering just individuals A and B the hypotheses are equally likely. In this work we show that the same is also true for the case where the mother of B is available for testing, notwithstanding the hypotheses being differently weighted if the mother of A is considered. Similar considerations are done for other kinship hypotheses and/or individuals/relatives. Irrelevance of the genetic profile of some specific relatives are mathematically demonstrated, and data obtained from 20,000 simulated families are presented for the other cases.