After speaking at well-attended EAC-BC meeting in 2012, forensic linguist Lorna Fadden returned to the stage last week for a highly anticipated follow-up. “I hope I don’t disappoint you,” she said. “You know when a sequel comes out, and it sucks?”
With an opening like that, Fadden had no cause for concern.
Fadden lectures in the department of linguistics at SFU, where she studies sociolinguistics and discourse analysis, as well as First Nations languages. She also runs a consulting practice in forensic discourse analysis, examining language evidence for investigations or trials in criminal and civil cases. These cases may involve hate speech, defamation, bribery, internet luring, plagiarism, and extortion, among other types of language-related crimes. She analyzes both linguistic form—grammatical structure, word choice, and prosodics—and linguistic function—meaning, social context, and pragmatics.
Fadden presented a historical case in which forensic linguistics played a starring role: in 1989, the Exxon Valdez, captained by Joseph Hazelwood, struck Prince William Sound’s Bligh Reef and spilled its crude oil cargo, resulting in one of the worst environmental disasters in history. There was wide speculation that Hazelwood was intoxicated at the time, and forensic linguists analyzed his recorded exchanges with the Coast Guard to find evidence that he was impaired.
Alcohol depresses the central nervous system, Fadden explained, impairing coordination, reflexes, and nerve transmission—basically everything you use when you talk. It also impedes your ability to recall words, as well as your ability to utter words in the correct sequence. Intoxication leads to misarticulation of certain speech segments: r and l sounds can become blended, and s and ts sounds can be palatalized to become sh. Suprasegmental effects of intoxication include slower speech, lower mean pitch, a wider pitch range, vowel lengthening, and the lengthening of consonants in unstressed syllables.
According to the Coast Guard’s recordings, Hazelwood’s speech had all of these characteristics 1 hour before, immediately after, and 1 hour after the Exxon Valdez ran aground but was normal 33 hours before and 9 hours after the accident.
At the time, forensic linguistics as a social science was relatively new. Hazelwood’s trial was the first time this kind of evidence was used in court, but because no witnesses could remember seeing Hazelwood drink and the jury may have been uncomfortable with this means of demonstrating drunkenness, he was acquitted.
Fadden then told us about some of her cases, one of which involved a series of menacing and highly critical letters being sent to a large company’s board of directors. These letters were sent anonymously, but the writer claimed to be a member of the company’s front-line staff or a mid-level manager. The language in the letters, accusing the directors of having “zero business acumen” and referring the company’s “value proposition,” as well as referring to “our managers”—unlikely for a low-ranking staff member to do—betrayed the writer’s higher rank. With Fadden’s help, the investigation uncovered that the writer was a high-ranking executive who’d been fired, and he was sent a cease-and-desist letter.
In another case, the mother in a custody dispute received a series of letters, supposedly from her kids, telling her they wanted nothing to do with her. Fadden’s role was to determine whether the children genuinely wrote the letters themselves. One letter, in her 7-year-old’s handwriting, mentioned that the kids did not “fully trust” their mother and agreed that they would spend time with her only on supervised visits. “Kids that age don’t use adverbs like ‘fully,’” said Fadden, and she doesn’t believe that kids have the meta-awareness implied by the letter. Occasionally we write something addressed to one person, knowing it will have a larger audience. In this case, the letters were written in a style that suggested the writer realized that others—lawyers, psychologists, and so on—may read them. Fadden’s analysis, along with a social worker’s assessment and psychologists’ assessments, led to a favourable outcome for the mother, who’d been accused of nefarious things that hadn’t been proven. “You have to be careful asking kids questions, because the questions we ask them often already suggest the answers,” said Fadden. “We rarely ask children information-seeking questions.”
Fadden’s third case was a more complex one: a woman had accused a man of drugging and sexually assaulting her, but eyewitness accounts, video surveillance, and toxicology suggested that her allegation was false. She faced a charge of public mischief, but she claimed she didn’t understand what happened during the police interview. Fadden had to assess whether she was legally competent by comparing her linguistic performance with what we’d expect from a native speaker in the same context. In her doctoral dissertation, Fadden had characterized a series of police interviews of first-time suspects, so she had a robust set of measures as benchmarks.
Cognitive deficiency is correlated with a slow speech rate, but the suspect had a relatively high speech rate, and it didn’t drop significantly from the beginning of the interview to the end (so not much of a fatigue effect). Fadden also looked at her turn latency (how much time elapses between the end of the interviewer’s question and her answer) and her pause ratio (how much she pauses compared with how much she speaks). All of these temporal elements were within normal ranges; nothing suggested that she was incompetent.
A stronger indicator of the suspect’s competence was in the way she manipulated specificity associated with details. Take, for instance, “this talk,” from most generic to most specific:
- Fadden’s giving a talk on Wednesday (type identifiable, not specific)
- There’s this talk on forensic linguistics on Wednesday (referential)
- The talk on forensic linguistics on forensic linguistics will be on Wednesday (uniquely identifiable)
- This/that talk on forensic linguistics is on Wednesday (familiar)
- I’ll be at that on Wednesday (activated)
- It’s on Wednesday (in focus—you don’t even have to name it)
(Fadden made sure we noted the distinction in specificity between “this talk” and “this talk.”) Through 2 hours of interviews, the suspect was adept at adjusting the level of specificity based on context, using generic language to describe what she claimed to have witnessed when she allegedly found herself in an unfamiliar environment but specific language when talking about details that the police officer had told her. Fadden concluded that she had normal cognitive status. The suspect eventually confessed to fabricating the story because she didn’t want her husband to find out she’d willingly slept with another man.
To end the evening Fadden challenged us to an exercise of authorship analysis. She gave us two writing samples from different blogs with similar topics and writing styles. We had to figure out who’d authored a third sample. From a superficial reading, most people in the room guessed that the first blogger was responsible, but Fadden showed that by comparing features like
- the number of words per sentence,
- the length of words,
- the use of adjectives and adverbs,
- the use of parentheticals,
- the use of discourse markers,
- the use of conjoined phrases, and
- the use of independent clauses,
her analysis showed that the second blogger was the likely author. Authorship analysis is a contentious field now because its effectiveness and accuracy aren’t completely understood, and there’s no standard method for carrying it out. As a result, it’s not admissible in court. But, like a polygraph, authorship analysis may help steer the direction of an investigation.