Judicial attitudes towards examining forensic evidence

The last two decades have witnessed a heightened scientific inquiry into various forensic disciplines. Significant research has been devoted to pattern matching disciplines which were developed to aid police investigation. While these disciplines were popular with investigating agencies, they were used without a robust inquiry into their scientific validity. Claims of a ‘match’ between the source and crime scene sample made by experts were met with very little scrutiny by judges and lawyers.

Research into pattern matching disciplines has shown that these claims lack any scientific basis. However, they found favour with the legal professionals for various reasons.

Firstly, courts have reposed their faith in forensic evidence due to the intuitive belief in the infallibility of science. This rests on the assumption that all forensic disciplines are indeed scientific. The culture of challenging the validity of these forensic disciplines was absent for a long time.

Secondly, the definitive and allegedly scientific claims of a ‘perfect match’ provided the trier of fact with a sense of misplaced sense of confidence in the guilt of the accused.

Third, once faulty forensic evidence was admitted and relied on by courts, it created a judicial precedent. The doctrine of stare decisis postulates that judges look at precedents to guide their decisions. While stare decisis has been developed to ensure consistency in law, it poses a unique challenge in the context of forensic evidence. Instead of gauging the scientific validity of the expert opinion, courts heavily rely on judicial precedents while scrutinising different types of forensic evidence. In doing so, the focus is on maintaining continuity in law as opposed to robustly examining the accuracy and reliability of evidence.

The approach of judges in examining forensic evidence reveals the inherent tensions which exist between legal and scientific inquiries. The focus of the legal system is to achieve final resolutions of disputes and maintain consistency in legal standards. However, science demands and encourages skepticism which may lead to discovery of new methods for testing, or disproving the assumptions underlying existing techniques. Therefore, the admission of reliable forensic evidence requires achieving synergy between law and science. It necessitates a change in judicial attitude where the focus is redirected towards examining if the forensic technique has scientific foundations and if it has been reliably applied in the case at hand. The adjudication of these issues ought to be guided by scientific principles too, as opposed to only previous judicial expositions on such evidence.