Modern Australian

Forensic linguists can make or break a court case. So who are they and what do they do?

  • Written by Georgina Heydon, Associate professor, RMIT University

If you’re an avid viewer of crime shows, you’ve probably come across cases in which an expert, often a psychologist, is called in to help solve a crime using their language analysis skills.

However, in real life it’s the job of forensic linguists like myself to provide such evidence in courts, here in Australia and around the world.

Forensic linguists can provide expert opinion on a variety of language-related dilemmas, including unattributed voice recordings, false confessions, trademark disputes and, of course, a fair share of threatening letters.

But what do we look for when doing this?

Reading between the lines (and everything else)

Linguistics is the scientific study of language. Thus, linguists are uniquely placed to provide expert opinions on how language is used. Linguists study:

  • grammatical structures, wherein changes in punctuation patterns between texts can signal different authors

  • semantics, which explores how speakers and listeners form meaning, such as when making sense of a written text

  • phonetics and phonology, which refer to the sounds of language. We can recognise subtle differences in the sound of a vowel when produced by different speakers, or by speakers of different dialects and languages.

  • sociolinguistics, which looks at how language use varies across different social groups. For example, we can identify when someone from a non-English language background might misunderstand a question. This is because the variety of English they’re familiar with would differ, in small but notable ways, from native English speakers.

Since the first known forensic linguistic case in 1953, all of the above abilities have proven invaluable in courts time and time again. Yet the work done by forensic linguists seems to largely elude members of the public.

Illustration of confused people. Sociolinguistics is a branch of language study focused on the relationship between language and various groups in society. Shutterstock

A widely misunderstood field

Ironically, a big problem for forensic linguists (and linguistics in general) relates to language. It comes down to how we use the word “linguist”.

Some people think this refers to a person who speaks many different languages, or is particularly fluent in their speech or writing. These non-technical interpretations are easy to conflate with the academic discipline of linguistics.

But apart from causing linguists a headache at dinner parties, does it really matter if people misunderstand what linguists do?

It seems so. Widespread ignorance on the vitality of forensic linguistics has led to some of the most egregious miscarriages of justice in Australian history.

In 2018, the Western Australia Court of Appeal overturned the conviction of manslaughter for Gene Gibson, an Aboriginal man with a cognitive impairment for whom English was a third language.

Police interviewed Gibson without an interpreter, assuming one wasn’t needed to assess his English fluency. This neglect resulted in Gibson spending nearly five years in prison for a crime he didn’t commit.

Lawyer Michael Lundberg speaks to the media outside the WA Supreme Court. In 2018, Gene Gibson was awarded a total A$1.5 million in compensation by the West Australian government, after being jailed for a crime he didn’t commit. Gibson’s lawyer Michael Lundberg (pictured) told the ABC the payment wasn’t as large as he’d hoped. Rebecca Le May/AAP

People who speak English as an additional language sometimes don’t know their legal rights in situations such as police interviews.

In the past, these defendants or witnesses have been treated as though they understood complex legal English simply because they could chat about the weather, or their family. Such casual conversations are not a suitable test for language fluency.

The verbose wild west of the web

Another example where linguistics intersects with criminals is found in the rapid increase in crimes involving digital communication. These online offences are made easy by the anonymity and reach allowed on social media platforms.

Correctly identifying individuals who post threatening, defamatory or false messages online is of chief importance for investigators as it can help protect those targeted.

Illustration of an on-screen text. Social media use has skyrocketed in the past decade, boosting the trend of ‘viral’ content. This has hugely shifted the defamation landscape. Shutterstock

This task, carried out by forensic linguists, is known as “authorship attribution”. It relies on correctly grouping together texts produced by the same author, by isolating textual features specific to that author.

These features are usually related to grammatical structure and are deeply embedded in each person’s individual authorial style. They are difficult to manipulate by would-be imposters.

Authorship attribution is certainly challenging, as there’s no “text fingerprint” or distinct pattern of language use that can be allocated to each of us. Still, big data analysis, combined with linguistic theory, is getting us closer to a reliable system.

Read more: Forensic linguists explore how emojis can be used as evidence in court

A “stylistics” approach, featured in one Australian Story episode last month, describes patterns of language that are similar or different between two specific texts.

But this approach makes no attempt to calculate how common these patterns might be in any other authored text. This oversight is typical of non-linguists attempting to undertake linguistic analysis, as they often don’t know what constitutes a common feature of language.

For instance, if two documents feature the word “cant” (“can’t” without an apostrophe), a non-expert may see this as a strong indicator of a common author.

But according to the Birmingham Blog Corpus — a collection of almost 630,000,000 words taken from blogs — this word is spelled without an apostrophe about 3.6% of the time.

Technology-facilitated analysis

More reliable methods of identifying authorship, or identifying a speaker in a voice recording, are possible with both specialised linguistic knowledge and computer processing power.

Advancing this field doesn’t require any fancy new technology. It requires more investment in Australia’s capacity for forensic linguistic research. In an increasingly digital world, in-depth research on text authorship and voice identification will prove crucial to future law enforcement.

It’s also important we increase awareness of the power (and limitations) of linguistic analysis among the general public, and especially among officers of the law and judiciary.

Bringing more linguistics into schools, such as with Victoria’s VCE English Language subject, would be a great way to equip the next generation of these experts.

Read more: Can criminal suspects be identified just by the sound of their voice?

Authors: Georgina Heydon, Associate professor, RMIT University

Read more https://theconversation.com/forensic-linguists-can-make-or-break-a-court-case-so-who-are-they-and-what-do-they-do-149920

NEWS

Home-delivered food has a huge climate cost. So which cuisine is the worst culprit?

ShutterstockOver the past few years, Australians have embraced online food delivery services such as UberEats, Deliveroo and Menulog. But home-delivered food comes with a climate cost, and single-use packaging is...

The economy can't guarantee a job. It can guarantee a liveable income for other work

When the coronavirus pandemic hit Australia in March 2020, the Morrison government took bold and imaginative action. The most notable examples were its income support programs – JobKeeper, paying a...

why you may have to buy a new device whether you want to or not

The Conversation, CC BYWe’ve probably all been there. We buy some new smart gadget and when we plug it in for the first time it requires an update to work.So...

To learn at home, kids need more than just teaching materials. Their brain must also adapt to the context

ShutterstockResearch during the first phase of remote teaching in Victoria reported some students found the workload “too high”, missed interactions with peers, felt their thinking ability was impaired, and reported...

Circa's Humans 2.0 is a visceral delight

Yaya Stempler/Sydney FestivalReview: Humans 2.0, directed by Yaron Lifschitz, Circa at Sydney FestivalThe black circular stage is lit by small towers of side-lights. Lights fade to black before suddenly revealing...

Do you feel undervalued and overworked? COVID-19 is likely to affect the employed too

ShutterstockThere’s no question the rising rate of unemployment is one of the worst consequences of the COVID-19 pandemic. The number of Australians seeking work is heading towards 10%, almost double...

restoring trade with China in a hostile political environment

The new trade minister, Dan Tehan, has been handed one of the Morrison government’s most demanding roles. Despite a lot of chest-thumping in government circles about the need to stand...

Despite appearances, this government isn't really Keynesian, as its budget update shows

It is tempting to think the Australian government’s decision to spend big – bigger than ever before, an unprecedented 33% of GDP this financial year according to the budget update...

The Pfizer vaccine may not be the best choice for frail people, but it's too early to make firm conclusions

Reports of about 30 deaths among elderly nursing home residents who received the Pfizer vaccine have made international headlines.With Australia’s Therapeutic Goods Administration (TGA) expected to approve the vaccine imminently...

Curious kids: how do gills work?

David Clode/Unsplash, CC BYHow do gills work? Tully, aged 7Great question, Tully! Animals on land breathe air, which is made up of different gasses. Oxygen is one of these gases...

There's no such thing as 'alternative facts'. 5 ways to spot misinformation and stop sharing it online

ShutterstockThe blame for the recent assault on the US Capitol and President Donald Trump’s broader dismantling of democratic institutions and norms can be laid at least partly on misinformation and...

As Trump exits the White House, he leaves Trumpism behind in Australia

Mick Tsikas/AAPThrough recent natural disasters, global upheavals and a pandemic, Australia’s political centre has largely held. Australians may have disagreed at times, but they have also kept faith with governmental...



News Co Media Group

Content & Technology Connecting Global Audiences

More Information - Less Opinion













Popular articles from Modern Australian

How Is Tequila Made?Why You Should Enlist The Services Of A Property StylistTop Luxury Resorts For A Restorative Staycation In AustraliaUnderstanding Employee Car Allowance Rates in Australia7 Bucket-List Worthy Experiences in DubaiThe Effects of Pollen Throughout the Year What Qualifications Are Required to Work as a Chef in Australia?How You Can Create A Café With A Shipping ContainerA Few Great Uses For Laundry DetergentHow To Make Living With Housemates SimplerGreat Tips For Buying Flowers For Valentine’s Day Mercedes-AMG GT Black Series Becomes The Fastest Sports Car Safety Tips You Need to Remember Before Contacting an ElectricianHow to Choose the Best Fishing Backup & Tackle BoxReasons You Need to Consider the Services of a Licensed Electrician