Trace Evidence

Locard’s exchange principle: When ever two objects come into contact with one another, there wil be cross-transfer of material which will be occur

Trce evidence: refers to any evidence that is small in size, such as hairs, fibers, paints, glass and soil, which would require microspoic analyiss

propability: frequancy which which an event will occur, something refered to as odds of occurrence

Product rule: when the requency of endepently occuring variables are multiplied togther to abtain an overall frequenct of occurence for the even of item

Baysian techniques: an alternative to classical or requent methods of analysing evidence

trace evidene is collected in a variety of ways, including use of forceps, tweeers, by hand, tape lift, or even vacuuming

primary and secondary transfer

• evidence can be transfered during the commission of the crime, as well as during the search process

• elimination hair/fiber samples may need to be abtainined

• prioritize the order of evidence collection

  • druggist fold is the primary method of edidence preservatioon (primary packaging)

• then put the druggist fold into a paper envelop or paper bag, and sealed for secondary packaging

glass is typically characterized as transfer evidence

• examination 0f gpass that has been facured can lead an inveestment which direction the impact originated

this can be usefull when detemining whether or not a window was broken from the indide or outsife

• Radial fracured: oriningating from the poin of impact and moving away from that point

• consentric fracures: concentric circles around the impact point

glass evidence is usually views as class evidence and is rarley indivisualistic

internaton forensic: automotive paint data is a searchable database of chemical and color information of originlumotive paints 7