trace evidence

• types of traces

  dna

  glass

  hair

  fibres

  tool marks
• glass sampling

  remove from window

  inside and outside

  if multicoloured recover each colour

  photograph before recovery

  package in rigid container
• evidential value fibres

  hair

  upper garment

  lower garment

  pockets

  soles of shoes
• transfer process

  glass fragmentation

  clothing retention
• trace evidence factors

  type/ age of glass

  layers of paint

  location where sample was obtained

  damage

  garment involved
• clothing retention factors

  time since trace was deposited on clothing

  washing- has garment been washed

  activity- how much movement has garment been subjected to

  texture
• glass sampling suspect

  take combings of hair

  take shoes

  remove lower garments

  never pull garments overhead
• wood/ paint recovery

  tool marks

  photograph

  seize wood

  take measurements

  protect tool and size
• evidential value of paint

  multi

  limited

  double

  single coloured

  single white
• fibre transfer factors


  donor

  recipient

  number of contacts

  pressure of contact

  location of contact

  area of conact
• fibre recovery methods

  tweezers

  single tape lift
• tool mark factors

  type

  pressure

  length of contact
• recovery considerations

  mark must be photographed

  measurements must be taken

  cast must be taken from both sides

  recover fully