“Science,”“common sense,” and DNA evidence: a legal controversy about the public understanding of science

Abstract

Law courts are important institutional settings in which public understanding of science is problematic. Courts have struggled with the question of how to handle scientific evidence in a system of justice in which lay jurors are responsible for deciding the facts of the case. Judicial conceptions of science and of jurors' capacities to understand scientific evidence inform decisions in particular cases. Such decisions, in turn, act as precedents that, for better or worse, embed judicial conceptions of public understanding of science into the workings of the legal system. This paper examines an English case in which the difference between “scientific” and “common sense” evidence was explicitly at stake. In this case Regina v. Adams, DNA evidence was used to convict the defendant of rape. The principal item of prosecutorial evidence was a match between DNA profiles developed from the defendant's blood and from semen recovered at the crime scene. Prosecution experts expressed the evidence in probabilistic terms, estimating a probability of one in 200 million that a DNA profile from a randomly chosen unrelated man in the relevant population would match the profile developed from the crime stain. Other so-called “common sense” evidence supported the defendant's not guilty plea. The case was appealed twice in the mid-1990s as the Court of Appeal deliberated over an innovative effort by the defense to counteract the prosecution evidence by converting the non-DNA “common sense” evidence into probability estimates. In its decisions, the Court reinstated a boundary between the “scientific” and “common sense” evidence, arguing that this boundary was necessary to preserve the jury's role as trier of fact. The paper's discussion of the court's boundary work addresses unresolved problems with the place of probability estimates in jury trials.

A Cannabis sativa STR Genotype Database for Australian Seizures: Forensic Applications and Limitations*

“…With appropriate consideration, there will be a range of circumstances where genetic analysis of C. sativa seizures will be of forensic value, be it for prosecutor or defense assistance in drug‐related crime or for intelligence gathering for other investigations. However, as in human forensics, genetic analysis must complement, rather than replace, other forms of evidence (41). With the establishment of this first C. sativa genetic database, the next step in the implementation of C. sativa DNA typing can now be handed to established forensic laboratories.…”

“A Faustian bargain?” Public voices on forensic DNA technologies and the National DNA Database

“…Governing the uses of genetic knowledge has generated extensive academic debate about the scientific, judicial and ethical issues raised in the development and public understanding of DNArelated technologies. Challenging views that forensic databasing would improve crime detection rates and reduce police time spent investigating each crime due to its capacity to both include and exclude suspects in criminal investigations (Schneider et al 1997), studies have highlighted technical issues in the relationship between scientific expertise and judicial decision-making (Jasanoff 1998, Lynch andMcNally 2003), the probative difficulties of forensic science evidence in general (Allen and Redmayne 1997, Cole 2001, Redmayne 2001, and the presentation and evaluation of DNA evidence in particular (Edmond 2000, Tracy andMorgan 2000).…”

DNA Behind Bars

“…While much excellent research has been done on how lawyers, judges, jurors, the FBI and the criminal justice system in general use and understand forensic DNA profiling and databases (Lynch & Jasanoff, 1998;Derksen, 2000;Cole, 2001;Johnson et al, 2003;Lynch & McNally, 2003;Cutter, 2004;Lazer, 2004;Bal, 2005;Jasanoff, 2006;Aronson, 2007;Dahl, 2008;Lynch et al, 2008;Williams & Johnson, 2008), 'views from inside' (Bosworth et al, 2005) have not yet been heard on this topic -this paper will hopefully provide a first step towards doing so. In addition, while studies of technologies often focus on the producers or the users of a technology, prisoners can be seen as a 'third constituency' 7 in the sense that they are the object of forensic DNA surveillance: DNA technologies are used upon them.…”