Physical Match Flashcards
Define PHYSICAL MATCH.
A physical match occurs when the examination of the physical characteristis of two or more pieces of evidence reveals that they are fragments from what was previously one continous object, and are therefore of a common origin.
Outline the ACE-V methodology as it relates to physical matches.
Analysis of the class and accidental characteristics of the unknown and known evidence, independently.
Comparison of the observable variations and correspondences of the characteristics from the unknown to the known.
Evaluation of the significance of the variations and correspondences and formations of an opinion.
Verfication of the process and opinion by another qualified examiner.
What are class characteristics?
Intentional or unavoidable characteristics that will be repeated and is shared by more than one object. Features that are inherent in an object due to the manufacturing process or its very nature.
eg colour, shape, pattern, make, diameter, composition, etc.
What are accidental characteristics?
Something that is randomly added or taken away from the original structure of the object that either causes or contributes to making the object unique from all other objects sharing the same class characteristics.
eg. cuts, tear, wear, glass break marks, fractures, etc.
What are the four opinions for physical match?
- Inconclusive - not enough detail to reach a meaningful conclusion.
- Exclusion - dissimilarity of characteristics are sufficient to demonstrate known evidence did not come from known.
- Similar - pieces could have a common origin. Class characteristics match, but insufficient accidental characteristics are present for a positive identification.
- Individualization/Identification - pieces were at one point in time a single unit.
