R V. T (2010)
Definition
UK Court of Appeal decision on footwear evidence likelihood ratios that expressed caution about numerical LR presentation where the underlying database was small. Controversial in the forensic science community; interpreted by some laboratories as requiring verbal-scale presentation and by others as requiring larger databases, not prohibiting LR evidence.
- Court
- England and Wales Court of Appeal
- Year
- 2010
- Subject
- Footwear-mark likelihood ratios
- Concern raised
- Small underlying databases
Common questions
What did R v T actually decide about likelihood ratios?+
It expressed caution about presenting numerical likelihood ratios to a jury for footwear evidence when the statistical database behind the number was small or of uncertain reliability, without banning likelihood ratios as a method.
Why is R v T considered controversial among forensic scientists?+
The community was split: some read the judgment as requiring a shift to qualitative verbal-scale conclusions, while others read it narrowly as demanding better validation data, and it is cited on both sides of the LR-versus-verbal-scale debate.
Related terms
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- FRStat
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