8127/frame/fm

 
 
and 
 
ease of divisibility
(fragmentation) of a mate-
rial — These influence the number and size of fragments available for
transfer. For example, a cotton fabric will divide much more easily
than a steel door when subjected to similar forces.
• The 
 
force for transfer
during contact and the 
 
transferability
of the
material — These determine how likely a daughter fragment will either
adhere to its parent piece or be transferred to a target.
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Principles and Practice of Criminalistics
• The 
 
abundance
of fragments transferred — The preceding factors,
combined with the initial abundance, will determine how many frag-
ments are transferred to a target.
• The 
 
persistence
of the fragment — This refers to the ability of a frag-
ment, once transferred from a source to a target, to adhere to the
target.
•
 
Secondary transfer
— This refers to a fragment transferred from its
source A to target B, and then transferred from target B to target C.
Detecting the fragment from source A on target C leads to the infer-
ence of contact between A and C, when in fact no such contact has
been made.
•
 
Unrelated transfer
— This refers to the possibility of fragments trans-
ferred and detected that are unrelated to the crime event.
These last two factors lead us to realize that the commission of a crime is
not the only time that fragments are transferred from a source to a target.
At any crime scene there is an overabundance of physical material, some
related to the crime, and much that is not. Unfortunately, Locard’s formu-
lation of transfer theory ignores the consideration of objects being transferred
when crimes are not being committed. This is an important limitation to be
incorporated into the final inference of a putative association between a
source and a target.