fingerprint comparison

• level 1

  arches 5

  loops 65 ulnar or radial

  whorls 30
• what’s ulnar and radial

  ulnar, slopes down the same side as the hand

  radial, slopes down the opposite side of the opposite hand
• level 2

  scars

  • can be perm or temp depending on the damage
  • used for identification

  creases

  • smaller white lines
  • perm or temp
  • not used for identification

  subsidiary ridges

  • smaller ridges
  • not always present
  • not used for identification

  look for

  • hooks
  • spurs
  • ridge ending
  • independent ridges
  • bifurcation
• interpretation

  ref to source and activity

  window, breaking an entry or cleaning

  pillow, suffocation or changing sheets
• comparison to reference fingerprint

  use ACEV

  analysis

  • assessment of crime scene mark
  • is it a friction ridge impression
  • appearance and condition
  • is it sufficient for comparison

  comparison

  • side by side comparison, usually leads to agreement or disagreement
  • is it quality sufficient
  • agreement on level 1 and 2

  evaluation

  • conclusion

  verification

  • another examiner examines it to see if they reach the same conclusion
• comparison

  look for

  identify, number and relative location of characteristics

  coincidence sequence (relationship between characteristics and fingerprint eg order and position), it must be identical to be a match
• ridgeology

  similar patterns

  similar ridge flow

  friction flow features

  same sequence
• porescopy

  compare sweat pores

  size

  number

  position