criminalistics

• what are the 6 concepts

  divisibility of matter

  principles of exchange

  identification

  individualistion

  association

  reconstruction
• examples of divisibility of matter

  trace evidence

  DNA

  drugs

  firearm

  fingerprint
• hierarchy of propositions

  source (individualisation and identification)

  activity (association)

  offence
• divisibility of matter


  matter divides into smaller components when sufficient force is applied, component parts can acquire new physical properties such as new edges, but the physiochemical properties remain the same as original
• consequences of divisibility of matter

  some characteristics retained by the traces are common to the original, lost/ changed or unique to the original

  leads to identification
• principles of exchange

  every contact leaves a trace (locards principle)
• consequences of principles of exchange

  traces can come from the offender, witness/victim and then picked up by offender or traces can be left by different entities who are involved in the crime
• identification

  consequence of divisibility of matter

  "characteristics are common to original"
• individualisation

  consequence of divisibility of matter

  "characteristics are unique to original"

  narrows down the class to one member

  answers the who and what question
• association


  consequence of principles of exchange

  "traces are left after every interaction"

  links a person to a crime and allows identification
• reconstruction

  ordering the associations based on physical evidence to answer where, how and when questions
• types of characteristics

  intrinsic = source = features such as size, texture, shape, physical properties

  extrinsic = activity = how is it formed eg number, amount, pattern, position