How Interpretation of Indistinct Covert Recordings Can Lead to Wrongful Conviction: A Case Study and Recommendations for Reform

Covert recording (‘bugging’) is now authorised in almost every major police investigation. Unfortunately, because the need for secrecy compromises control over recording conditions, the audio is often indistinct. Legal practice regarding the use of indistinct covert recordings in trials has evolved haphazardly over the past 30 years, with no consultation of phonetic science. This has resulted in a number of anomalies, notably the fact that detectives are allowed (as ‘ad hoc experts’) to present their own transcripts of indistinct audio to ‘assist’ the jury in interpreting the audio evidence. This chapter highlights problems with this practice via a case study of a murder conviction obtained on the basis of a demonstrably inaccurate police transcript, then suggests directions for reform.