SLIDE 7 Acoustic / phonetic methods
- Blind research!
- Two co-workers, P1 & P2
- Materials anonymized by P1
– Handles all information and material – Adds foils in case of speaker identification/verification – Randomizes the order of presentation of materials
- questioned and reference material, and foils all together
– Numbers the materials, without reference to source
Acoustic / phonetic methods
- P2 runs the first – blind –
acoustic/phonetic analyses
- P2: first conclusion about grouping of
materials
- P1 provides the key
- P2 runs a second analysis with all material
and (necessary) information present
Implications for forensic research
- Forensic research: highly responsible
– Unintentionally prone to biases
- Forensic experts international: Not only
critical on conclusions and reporting
- evaluate methodology!
- Also analytic phase: scrutiny.
– Improve scientific objectivity – Take precautions!
IAFPA
Standards
to avoid case information to contaminate evidence?
Thank you for your attention! Literature
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