ֱ̽ of Cambridge - Kirsty McDougall /taxonomy/people/kirsty-mcdougall en Brits still associate working-class accents with criminal behaviour – study warns of bias in the criminal justice system /research/news/brits-still-associate-working-class-accents-with-criminal-behaviour-study-warns-of-bias <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/885x428-the-old-bailey-art-de-cade-via-flikr-under-cc-license.jpg?itok=hPk1Q3CK" alt=" ֱ̽Old Bailey in London. Photo: Art De Cade via Flikr under a CC license" title=" ֱ̽Old Bailey in London. Photo: Art De Cade via Flikr under a CC license, Credit: Art De Cade via Flikr under a CC license" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Research led by the ֱ̽ of Cambridge, in collaboration with Nottingham Trent ֱ̽, raises serious concerns about bias in the UK criminal justice system due to negative stereotyping of accents.</p>&#13; &#13; <p>These stereotypes, the researchers argue, can affect all parts of the system from arrest to sentencing, and undermine not only suspects and defendants, but also the testimony of witnesses. ֱ̽study is particularly concerned about accented speakers being incorrectly selected from voice identification parades.</p>&#13; &#13; <p> ֱ̽findings, published in <em>Frontiers in Communication</em>, suggest that despite progress in equality and diversity in some parts of British life, including ‘working-class’ and regional accents becoming more prominent on television and radio, harmful stereotypes remain.</p>&#13; &#13; <p>“Our findings bring into sharp focus the disadvantage that speakers of some accents may still face in the criminal justice system,” said lead author, Alice Paver, from the ֱ̽ of Cambridge’s Phonetics Laboratory and Jesus College, Cambridge.</p>&#13; &#13; <p>“Voices play a powerful role in the criminal justice system and police officers, lawyers and juries are all susceptible to judging voices based on stereotypes, whether they're aware of it or not. As things stand, listeners think some accents sound guiltier than others and we should all be concerned about that.”</p>&#13; &#13; <h3><strong> ֱ̽test</strong></h3>&#13; &#13; <p> ֱ̽researchers, from Cambridge and Nottingham Trent ֱ̽, asked 180 participants (~50:50 gender split) from across the UK to listen to recordings of ten regionally-accented male voices: Belfast, Birmingham, Bradford, Bristol, Cardiff, Glasgow, Liverpool, London, Newcastle and Standard Southern British English (SSBE), also referred to as RP.  </p>&#13; &#13; <p>Participants were then asked to rate the voices on 10 social traits – ‘Educated’, ‘Intelligent’, ‘Rich’, ‘Working class’, ‘Friendly’, ‘Honest’, ‘Kind’, ‘Trustworthy’, ‘Aggressive’ and ‘Confident’; as well as on 10 morally ‘good’, ‘bad’ and ‘ambiguous behaviours’, which included a range of crime types.</p>&#13; &#13; <p>These behaviours included: ‘Return a lost wallet to its owner’, ‘Stand up for someone who is being harassed’, ‘Cheat on a romantic partner’, ‘Report a relative to the police for a minor offence’, ‘Drive dangerously’, ‘Physically assault someone’, ‘Shoplift’, ‘Touch someone sexually without consent’, ‘Vandalize a shop front.’</p>&#13; &#13; <p> ֱ̽study used a wider range of recorded accents, behaviours and criminal offences than previous research which has tended to focus on criminal behaviour in general or the binary of white versus blue-collar crime. This study included crimes which are not class stratified, such as a driving offence and a sexual offence, and is the first to identify links between listener perceptions of morality, criminality, and social traits.</p>&#13; &#13; <p>To ensure their results would be valid in a criminal justice context, the researchers created voice samples in a similar way to how they are constructed for voice ID parades. ֱ̽aim was to mimic, as closely as possible, how a juror or earwitness would experience them.  </p>&#13; &#13; <h3><strong>Findings: Status, class and regions</strong></h3>&#13; &#13; <p> ֱ̽results show that people with non-standard accents are more likely to be associated with criminal behaviour but that there is significant variation in perceptions between accents.</p>&#13; &#13; <p> ֱ̽RP-like accent was perceived as the least likely to behave in criminal ways, while the Liverpool and Bradford accents were the most likely.</p>&#13; &#13; <p>Alice Paver said: “ ֱ̽strongest connection we found was between people's perceptions of class or status, negative traits such as aggression, and how they think someone is going to behave, particularly when it comes to crime. This is the first time that a concrete link between traits and behaviours has been made in the context of accent judgements.”</p>&#13; &#13; <p>Unlike previous findings, the researchers did not observe a relationship between ‘solidarity traits’ (such as kindness and trustworthiness) and any behaviours. Status proved a much more important predictor of behaviours, re-enforcing the link between social class and expectations of behaviour in the UK.</p>&#13; &#13; <p>However, non-English accents, in particular Belfast’s and Glasgow’s, were rated significantly less likely to behave in criminal ways than almost all other accents. They were also thought most likely to ‘stand up for someone being harassed’ (‘honourable behaviour’) and least likely to exhibit ‘morally bad’ behaviours.</p>&#13; &#13; <p>Alice Paver said: “Our findings show that perceptions of speakers of regional accents and how status, social attractiveness and morality interact are much more complex than previously assumed. We need a much more nuanced understanding of how accents are evaluated when it comes to different crime types.”</p>&#13; &#13; <h3><strong>Findings: Sexual offences</strong></h3>&#13; &#13; <p> ֱ̽London and Liverpool accents were rated most likely to touch someone sexually without consent, but they were very closely followed by the RP accent. Participants thought the RP accent was more likely to commit a sexual assault than any of the other offences tested.</p>&#13; &#13; <p>“This finding simultaneously undermines certain traditional stereotypes about both higher status and working-class men,” Alice Paver said. “This may indicate shifting perceptions of the ‘type’ of man who can and does commit sexual offences.”</p>&#13; &#13; <p> ֱ̽Glasgow and Belfast speakers were thought the least likely to commit this sexual offence.</p>&#13; &#13; <p> ֱ̽study found that participants perceived this sexual offence as distinct from other criminal behaviours. Poor ratings for it clustered with those for non-criminal ‘morally bad’ behaviours, namely ‘being unfaithful to a romantic partner’ and ‘lying on a CV’.</p>&#13; &#13; <h3><strong>Findings: Newcastle and Birmingham</strong></h3>&#13; &#13; <p>Previous studies have found that the Newcastle accent rates highly for traits such as friendliness, but this study recorded less positive ratings for kindness, honesty, friendliness and trustworthiness.</p>&#13; &#13; <p>By contrast, the Birmingham accent, which has rated poorly in previous research across these measures, performed better than Bradford, Bristol, Liverpool, London and Newcastle in this study.</p>&#13; &#13; <p>“Although relatively stable over time, language attitudes can change,” Alice Paver said. “This might be the case for the Birmingham and Newcastle accents. But previous studies have often asked people what they think of an accent label whereas we played them an actual voice. That’s a very different stimulus so we’re not surprised people reacted differently.”</p>&#13; &#13; <h3><strong>Bringing about change</strong></h3>&#13; &#13; <p> ֱ̽study contributes to the <a href="https://www.phonetics.mmll.cam.ac.uk/ivip">Improving Voice Identification Procedures</a> project. Its team of researchers is currently drafting revised guidelines for voice identification parades aimed at police officers and legal professionals.</p>&#13; &#13; <p>They support the use of pre-tests to screen for bias against foil or suspect voices to make sure that they don't stand out as sounding unduly guilty or untrustworthy.</p>&#13; &#13; <p>“Jurors are not currently made aware of or warned against letting voice- or accent-based prejudice sway their decisions,” Paver said. “If we're asked to judge whether someone is guilty or not, and they've got a particular accent, we need to be sure we're not making that judgment because we think they sound like a bad guy.”</p>&#13; &#13; <p> ֱ̽researchers hope that future studies will examine even more offence types; further explore the relationships between perceptions of criminality and other, non-criminal, behaviours; and make use of a broader range of voices for each accent to tease apart the effect of individual voices and the strength of regional accents.</p>&#13; &#13; <p> ֱ̽research was carried out in collaboration with Professor Natalie Braber and Dr David Wright of Nottingham Trent ֱ̽’s School of Arts and Humanities, and Dr Nikolas Pautz, of NTU's Dept. of Psychology.</p>&#13; &#13; <p> </p>&#13; &#13; <h3><strong>Funding</strong></h3>&#13; &#13; <p>This research was supported by the United Kingdom Economic and Social Research Council as part of the project Improving Voice Identification Procedures (IVIP), reference ES/S015965/1. Additional funding was provided by the Isaac Newton Trust.</p>&#13; &#13; <h3><strong>Reference</strong></h3>&#13; &#13; <p><em>A. Paver, D. Wright, N. Braber and N. Pautz, ‘<a href="https://www.frontiersin.org/journals/communication/articles/10.3389/fcomm.2024.1462013/full">Stereotyped accent judgements in forensic contexts: listener perceptions of social traits and types of behaviour</a>’, Frontiers in Communication (2025). DOI: 10.3389/fcomm.2024.1462013</em></p>&#13; </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>People who speak with accents perceived as ‘working-class’ including those from Liverpool, Newcastle, Bradford and London risk being stereotyped as more likely to have committed a crime, and becoming victims of injustice, a new study suggests.</p>&#13; </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">Listeners think some accents sound guiltier than others and we should all be concerned about that</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Alice Paver</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="https://www.flickr.com/photos/duncanh1/38551767860/in/photolist-55jwWq-85y3b5-85y1M9-21JFTsL-2j7gGqZ-Prz4sq-2iYP3TH-egcpLi-85y1mC-cafCjA-RfuBHs-cafB1J-2kL3Ehy-egi8Tb-5zJxPa-8AqBAj-awRrL-2iYMf2n-2kGwF4S-2pxtAro-oTAByJ-2iZ1KFw-2q7rf8X-5sW4oc-8qgX2d-VMfjjK-2j9LkmU-heMSqs-9SiTMc-GWDaoM-6stzV9-gXMT8L-2q6vDvL-25rLmJT-6cqxGu-qta1Y9-wrysRr-85y24J-6rs5GJ-24Qh2GU-2nMhX1R-9SPCGS-2k5yVRw-anmevj-gQapYw-2kad2vK-2iYNMBa-2na5S86-EvxeMR-4e4Pu7/" target="_blank">Art De Cade via Flikr under a CC license</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even"> ֱ̽Old Bailey in London. Photo: Art De Cade via Flikr under a CC license</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br />&#13; ֱ̽text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p>&#13; </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div><div class="field field-name-field-license-type field-type-taxonomy-term-reference field-label-above"><div class="field-label">Licence type:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/taxonomy/imagecredit/attribution">Attribution</a></div></div></div> Fri, 17 Jan 2025 07:00:00 +0000 ta385 248624 at Can a voice identify a criminal? /research/news/can-a-voice-identify-a-criminal <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/111117-ear-travis-isaacs.jpg?itok=212RzbZt" alt="Ear" title="Ear, Credit: Travis Isaacs from Flickr" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Recognising a voice is a familiar experience for most people – identifying a friend’s voice over the telephone, recognising the voice of a well-known personality on the radio, hearing the voice of a colleague call out from behind. But why do voices sound distinctive? Given our ability to recognise individuals, it seems reasonable to assume that voices are unique, but it has not been scientifically demonstrated that all voices are measurably distinctive. In spite of the impression given by televised crime shows, as yet there is no technique available to identify a speaker with 100% reliability.</p>&#13; <div class="bodycopy">&#13; <p>This is a serious problem for forensic speaker identification, a branch of forensic phonetics in which a phonetician is asked to identify an unknown speaker whose voice has been recorded during the committing of a crime, for example a bomb threat, ransom demand, hoax emergency call or drug deal. ֱ̽phonetician compares the incriminating recording with samples of speech from a suspect with a view to identifying the perpetrator or eliminating the suspect. These cases are often controversial, and since the extent to which an individual’s voice is idiosyncratic has not yet been established, research in this area is crucial.</p>&#13; <p>A key problem in attempting to characterise a speaker is that each individual’s voice can vary greatly. We change our voices depending on who we are talking to, how formal the situation is, the emotion we wish to express and whether there is background noise. Speakers’ voices also change if they are tired, drunk or have a cold or sore throat, and of course speakers can disguise their voices. So a voice is much more complicated to capture than a fingerprint, which is a fixed, unchanging feature of an individual.</p>&#13; <p><strong>DyViS: investigating speech</strong></p>&#13; <p>A team of researchers in the Department of Linguistics – Dr Kirsty McDougall, Dr Gea de Jong, Toby Hudson and Professor Francis Nolan – is carrying out innovative research in speaker identification in the DyViS project (Dynamic Variability in Speech: A Forensic Phonetic Study of British English), funded by the Economic and Social Research Council (ESRC).</p>&#13; <p>To investigate the problem of variation within a speaker’s voice, the DyViS team have compiled a large-scale database of recordings of southern British English spoken across a range of speaking styles. Speakers participated in several tasks: a mock police interview where they were required to ‘lie’ about a particular scenario, a telephone call with a friend involving a more casual and relaxed style of speech, and a number of reading tasks. All of the speaking tasks included a particular selection of words that the participants had to utter in different contexts. These data enable the researchers to investigate how phonetic features of these words change for a given individual across the different speaking styles, and to what extent these features can be used to distinguish individuals.</p>&#13; <p><strong>Identifying the speaker</strong></p>&#13; <p>One particular feature being examined is a phenomenon known as ‘formant frequency dynamics’. Formant frequencies are the resonances of the vocal tract during speech – the frequencies at which vibrations of air are at maximum amplitude in the vocal tract in speech sounds such as vowels. Formant frequencies appear as roughly horizontal dark bands on a spectrogram, a computer-generated representation of the acoustic speech signal. These frequencies are powerful cues to speaker identity since they are determined by both the physical dimensions of a speaker’s vocal tract and the way the speaker configures the vocal organs to produce each sound.</p>&#13; <p>Previous research on speaker differences has typically measured the formant frequencies only at the centre of the sound. ֱ̽DyViS research goes beyond these ‘static’ measures to investigate the dynamics of formant frequencies, which reflect the movement of a person’s speech organs and are likely to reveal more fine-grained differences among speakers. Just as people exhibit personal styles for walking, running and other skilled motor activities, they move their vocal organs in individual ways when producing speech.</p>&#13; <p>Dr McDougall’s experiments have investigated the speaker-distinguishing potential of the formant frequency dynamics of the vowel sound in spoken words like bike and hike, of the vowel sound in who’d, and of sequences containing an ‘r’ sound preceded and followed by vowel sounds such as a route and a rack. ֱ̽work shows that formant frequency dynamics carry considerable speaker-specific information. By taking measurements along the formant contours surrounding the centre of a speech sound, a significant improvement in speaker discrimination is achieved.</p>&#13; <p><strong>Forensic phonetics</strong></p>&#13; <p>Together with research into other features of speech being investigated by the DyViS team, this work offers crucial new directions for solutions to the problem of extracting a speaker’s ‘signature’ from the speech signal. Findings from the DyViS project suggest that dynamic features of speech could provide a clue in speaker identification, which has clear applications in forensic evidence – in comparing voices and speech for purposes of identification, and in analysing speech recordings.</p>&#13; <p> ֱ̽research also has important implications for phonetic theory. Current models of speech production and perception do not provide a good explanation of the role of individual variation in speech communication. ֱ̽analysis of dynamic features of speech being undertaken by the DyViS team will lead to important theoretical developments in these areas, contributing to our understanding of how individual speakers can communicate with the same language yet sound so different from each other.</p>&#13; </div>&#13; </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Innovative research in the Department of Linguistics suggests that dynamic features of speech could provide a clue to forensic speaker identification.</p>&#13; </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">A key problem in attempting to characterise a speaker is that each individual’s voice can vary greatly. We change our voices depending on who we are talking to, how formal the situation is, the emotion we wish to express and whether there is background noise.</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Travis Isaacs from Flickr</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Ear</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/3.0/"><img alt="" src="/sites/www.cam.ac.uk/files/80x15.png" style="width: 80px; height: 15px;" /></a></p>&#13; <p>This work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/3.0/">Creative Commons Licence</a>. If you use this content on your site please link back to this page.</p>&#13; </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Sat, 01 Sep 2007 00:00:00 +0000 tdk25 25616 at