R V. Mohan (1994) + White Burgess Langille Inman (2015)
Definition
Canadian Supreme Court framework for forensic-expert admissibility: Mohan sets relevance + necessity + qualification + no exclusionary rule; White Burgess adds an independence and impartiality threshold the expert must satisfy to give opinion evidence.
- Court
- Supreme Court of Canada
- Combined test
- Mohan (1994) + White Burgess (2015)
- Added threshold
- Expert independence and impartiality
- Applies to
- All Canadian expert evidence
Common questions
How does this combined framework affect an impression-evidence examiner testifying in Canada?+
The examiner must satisfy Mohan's relevance, necessity and qualification criteria, then also demonstrate under White Burgess that their opinion is impartial and unbiased by which party retained them, or it can be excluded before the jury hears it.
Can a challenge under White Burgess exclude evidence even if the expert is well qualified?+
Yes. Qualification and independence are assessed separately, so a highly credentialed expert whose report shows clear advocacy for one side can still have their opinion ruled inadmissible on the impartiality threshold alone.
Related terms
- Class Characteristics (Footwear)
- The manufactured outsole design features shared by all examples of a specific shoe model: tread pattern, size, shape, and logo placement.
- Dental Stone
- A gypsum-based casting material harder and finer than plaster of Paris. Preferred for forensic 3-D casts because it captures detail at the...
- ESLA (Electrostatic Dust-Print Lifter)
- A device that applies a high-voltage static field to a metallised film, attracting dust particles from a footwear impression on a hard...
- Perpendicular Camera Alignment
- The requirement that the camera lens be directly above the impression centre with the sensor plane parallel to the impression plane; prevents...
- Randomly Acquired Characteristics (RACs)
- Post-manufacture features (cuts, gouges, embedded material, crack patterns) unique to a specific shoe sole or tyre; the highest-level individualising features in impression...
- SICAR (Shoeprint Image Capture and Retrieval)
- FBI and Foster and Freeman (UK) outsole design database used for class-characteristic database searches; referenced in US, UK, Australian, and Canadian forensic...
- Snow-Print Wax
- A spray wax applied in thin coats to snow impressions before casting to provide a thermal barrier, allowing Dental Stone casting without...
- Subclass Characteristics (Footwear)
- Features shared by a subset of shoes from the same mould or production batch; may mimic individual characteristics if not properly distinguished.
- SWGTREAD
- Scientific Working Group for Shoeprint and Tire Tread Evidence; US body that developed the dominant guidelines for footwear and tyre-mark examination, class-subclass-individual...
- Tracking Evidence (TE) Database
- FBI database of tyre tread design patterns, used for class-characteristic identification in tyre-mark cases; accessible to partner agencies internationally.
- Treadmate
- RCMP database of outsole designs for footwear comparison, used by Canadian forensic laboratories and accessible to partner agencies.