CH. 12: THE FORENSICS LABORATORY 20forensics%20lab

CH. 12: THE FORENSICS LABORATORY

http://picsicio.us/keyword/csi%20forensics%20lab/

I. Forensics Lab

A. Must be accredited and are monitored to keep this accreditation

B. Quality assurance program

1. Necessary to meet accreditation requirements

2. Includes education of staff, peer review of results, evidence

handling, lab security, proficiency tests, etc.

(Proficiency tests = simulated forensic cases produced

internally or by outside testing agency)C. Director of lab = criminalistD. Association with a law enforcement agency helps with the

free EXCHANGE of info and access to CS and physical evidence

II. Criminalist

A. Difference between forensics and criminalistics 1. forensics = more general

--Can apply to any # of scientific disciplines

(ex. anthropology and odontology)

2. Criminalist = a scientist who applies the principles of primarily biology, physics, and chemistry to evidence analysis AND is also trained in crime scene investigation and reconstruction

B. Role of criminalist1. Provide investigative leads . . . .How?

a. Through scientific evaluation of physical evidence

and a crime scene reconstruction

b. Report results and conclusions of the scientific evaluations

II. Criminalist (continued)

II. Criminalist (continued)

B. Role of a criminalist

2. To act as an . . .

a. Investigator—asking questions, communicating with police

b. Educator—educate individuals at all levels of a case (i.e. law enforcement officers, CSI, attorneys, judges, etc.)—expert testimony

c. Student—must stay current and continue to learn because of advancing technology and trends

III. Classifying and using physical evidence in a lab

A. Reconstruction Evidence

1. Provides info about events preceding, occurring during, and after a crime

2. Three commonly used tools to help locate reconstruction evidence

a. Luminol = chemical that reacts with minutes quantities of blood

http://science.howstuffworks.com/luminol1.htm

III. Classifying and using physical evidence in a lab

A. Reconstruction Evidence

1. Provides info about events preceding, occurring during, and after a crime

2. Three commonly used tools to help locate reconstruction evidencea. Luminol = chemical that reacts with minutes quantities of blood

b. Alternate light source = detects body fluid stains,

fibers, other compounds that

fluoresce under various

wavelengths of light

  c. Blood stain analysishttp://www.knoxandassociates.com/evidence.php

http://science.marshall.edu/murraye/Blood%20Spatter%20Lab.html

III. Classifying and using physical evidence in a lab(continued)

B. Associative Evidence 1. Is evidence that can be used to associate or dissociate a

suspect to a crime2. Further subdivided into . . .

a. Individual or identification evidence = evidence is linked to a particular sourceEx. fingerprints, DNA profiles, some impressions, and fracture matches

b. Class characteristic evidence= evidence is associated with a group

and not considered unique--Conclusions regarding class

characteristic evidence are limited

Activity

http://forensics.rice.edu/

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