chapter 4

Identifying & analyzing blood stains

if blood at the scene is fresh & relatively uncontaminated, identification is not difficult one prelim field test involves the use of hemident blood analyses is important bc of the value of DNA typing

Collecting glass & paint evidence

paint may be collected from the suspect's tools or clothing -paint can be collected in dried chips - glass is a common form of evidence at burglary scenes

Questioned documents

photocopier xams age of documents burned or charred paper altered or obliterated writing writing instruments mechanical impressions instruments typewriting

Comparison samples

unknown or questioned samples -recovered crime scene sample whoe source is questioned - questioned evidence that may have been transferred to an offender during the commission of a crime & been taken away by him/her

Bullet Identifications

when a bullet passes through the barrel of a weapon distinctive scratches are caused these scratches can be compared to bullets fired through firearms in question - identification is affected by the condition of the gun & of the bullets.z

Cloth fragments & impressions

-Fibers are of greater value as evidence

Questioned documents

-handwriting & handprinting exams there are 3 types of forgery -traced forgery -simulated forgery -freehand forgery

Firearm evidence

Determination from firearms evidence lab exam of firearm evidence may answer the following questions. -was this bullet fired from this weapon -what can be learned from bullet - what determinations can be made from cartridge cases -what miscellaneous determinations can be made by examination of firearms evidence. `

Forensic Dentistry

Forensic odontology is a specialty that relates dental evidence to investigation analyses of a bite mark had played a major role in many cases -teeth marks left in food or other materials -bit marks can help eliminate or identify suspects

Tool marks

Identify the type of tool that made the mark or impression establish the action used to operate the tool specify the size & other charactersitics of the tool -identify unusual featers

Footwear impressions

Photographs of footwear impressions at a crime scene

3 broad categories of latent fingerprints

Plastic Prints Contaminated/visible prints Latent/invisible prints

RUVIS

Reflected ultraviolet imaging system

Hair

has a lot of stuff on it do not submit wet hairs to the lab, allow hair to dry

Known samples

standard/reference sample control or blank sample elimination sample