How can you effectively use phonetics in forensic linguistics?

1 Voice identification

One of the most common tasks for forensic phoneticians is to determine whether a speaker in a recording is the same as a suspect or a witness. This involves comparing various acoustic features of the speech, such as pitch, intensity, duration, quality, and formants. However, voice identification is not a simple matter of matching sounds. There are many factors that can affect how a person speaks, such as mood, health, stress, age, dialect, background noise, recording quality, and disguise. Therefore, forensic phoneticians need to use careful methods and statistical analysis to assess the likelihood of a match or a mismatch, and to acknowledge the limitations and uncertainties of their conclusions.

2 Speaker profiling

Another way that phonetics can be used in forensic linguistics is to create a profile of a speaker based on their speech characteristics. For example, phonetics can help to estimate the speaker's age, gender, ethnicity, education, social class, and geographical origin. This can be done by analyzing the speaker's use of phonetic variables, such as vowel quality, consonant articulation, intonation, stress, and speech rate. However, speaker profiling is not an exact science, and it can be influenced by stereotypes, biases, and expectations. Therefore, forensic phoneticians need to be cautious and critical when interpreting and presenting their findings, and to avoid overgeneralizing or oversimplifying the relationship between speech and identity.

3 Speech enhancement

Sometimes, the speech evidence in a forensic case is not clear or audible enough to be analyzed or understood. This can be due to factors such as low volume, distortion, interference, or noise. In such cases, phonetics can help to enhance the speech signal and make it more intelligible. This can be done by using various techniques, such as filtering, amplification, noise reduction, spectral analysis, or waveform editing. However, speech enhancement is not a magic solution, and it can also introduce errors or artifacts that can affect the accuracy or reliability of the speech evidence. Therefore, forensic phoneticians need to be transparent and ethical when applying and reporting their methods, and to avoid altering or manipulating the speech signal beyond recognition.

4 Text analysis

Phonetics can also be used to analyze written texts that are related to speech, such as transcripts, notes, messages, or documents. For example, phonetics can help to identify the author of a text by examining their spelling, punctuation, grammar, vocabulary, and style. This can be done by looking for phonetic clues, such as spelling errors, phonetic spelling, dialect features, foreign accents, or idiolectal patterns. However, text analysis is not a straightforward process, and it can be affected by factors such as context, purpose, audience, genre, and medium. Therefore, forensic phoneticians need to be aware and respectful of the diversity and complexity of language use, and to avoid making assumptions or judgments based on superficial or incomplete evidence.

5 Linguistic evidence

Finally, phonetics can be used to provide linguistic evidence in court or in legal proceedings. This can involve presenting and explaining the results of phonetic analysis, answering questions, giving opinions, or challenging or supporting other experts. However, linguistic evidence is not always accepted or understood by judges, lawyers, or juries, who may have different expectations, standards, or perspectives on language and speech. Therefore, forensic phoneticians need to be clear and concise when communicating their findings, and to use appropriate and accessible language, examples, and visual aids. They also need to be honest and objective when expressing their opinions, and to acknowledge the strengths and weaknesses of their evidence.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?