UK Courts Still Tell Jurors to Judge Lies by Body Language
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- UK courts direct jurors to assess witnesses' body language and demeanour, with Scotland advising jurors they may consider "body language in giving" evidence, and England and Wales instructing jurors not to take so many notes that they are "unable to observe the manner/demeanour of the witnesses"
- In 1994, an English jury consulted a Ouija board during a murder retrial to ask the deceased who killed them; a retrial was ordered and the defendant was found guilty again
- Research shows eye-avoidance is the least trustworthy body-language cue for detecting lies — liars maintain eye contact because they need to monitor the listener's reactions and adapt their story in real time
- Facial-feature bias affects courtroom outcomes: attractive defendants are more likely to be found not guilty or to receive shorter sentences
- Linguistic analysis is more reliable because lying is cognitively demanding, leaving liars with less control over word selection, grammar, length, and construction of what they say
- Liars often self-correct, replacing the first-person "I" with the plural "we" (e.g., "I … we thought", "I … we didn't") to create distance from the content of their statement
- People recounting real events use sensory-perceptual details ("screeching tyres … felt my heart beating"), while liars fabricating an experience instead refer to their internal thought process ("I remember thinking … I tried to recall")
Why it matters: UK jurors are being pointed toward a lie-detection method — demeanour and body language — that decades of research show is unreliable and vulnerable to appearance-based bias, while linguistically grounded indicators of deception go unused in judicial guidance, with the potential to distort verdicts in serious criminal trials.
