The Role of Forensic Phonetics in Legal Investigation: A Case Study of Two Speaker-Identified/Unidentified Recorded Samples

Abstract

The study sheds light on the growing role forensic phonetics has recently been given in legal investigation, particularly in cases of speaker identification and identity authentication. Though this field of study is relatively new, strenuous efforts have been exerted by its founders, namely John Baldwin, Peter French and Francis Nolan among others, to come up with a concrete body of principles and methodologies on which the phonetic analysis of samples under legal investigation could be built. To prove this, the study is divided into two parts. Part one traces back the study of forensic phonetics to its origins with special emphasis given to its major methods of application: analysis of recordings, speaker profiling, speaker identification and construction of voice line-ups in ear-witness testimony. The second part of the study is based on a case study of two recorded samples, one for an unknown person speaking on the phone and the other for an identified person recorded in prison. By analyzing the different occurrences of a specific word (believe) in the two samples using Praat, the study aims to show the degree to which forensic phonetics can be accurate in solving cases of speaker identification and identity authentication under legal consideration.