Forensic Quiz 1 Flashcards
Forensic Science
the application of science to matters involving the law
Biology,Anatomy Etymology,,Chemistry,anthropology,behavioral sciences,criminology,physics,mathematics(forensic accounting,geometry,trigonometry,statistics),engineering,dentition,IT
psychology-Phd
psychiatry-M.D(prescribe medication
Crime Scene Investigator characteristics
Usually a police officer
Learn from Forensic Scientist on how to recognize evidence at a crime and to how to collect it as wells as preserve it/protect it from contamination plus document it
Maintain a chain of custody of evidence
Forensic Scientist
Usually a civilian
Provide training to the Crime Scene Investigator
½ the job in the lab
½ job in court(testifying evidence)
Chain of Custody
when a piece of evidence is recovered that evidence is labeled or tagged then it enters the systems and who has access is recorded, this protects the integrity of the evidence in court
Basic Services of a Crime Lab
Physical Science Unit-chemistry, physics,geology
Biological Science nit-anatomy,blood,DNA,bodily fluids
Firearms Unit-weapons bullets
Document Examination Unit
Photography Unit
Scientific Method
essense of forensic evidence that undegoes scientific inquiry
Scientific Inquiry
science derives the integrity of adherence to strict guidelines that ensure that the careful systematic collection, organization and anylsis of information
Who has done it (crime/forensic science) Steps
1.Begins by formulating a question worth of investigation ex.who killed the wife.
2.Formulate a hypothesis-a reasonable explanation proposed to answer the question
3.collect evidence
4.Analyze evidence
5.Arrest the perpatrator,trail by jury,guilty verdict leads to jail
Medical/Study Research Steps
1.Begins by formulating a question worthy of investigation ex.does smoking cause cancer
2.Formulate a hypothesis
3.Collect data/observations
4.Analyze data/observation
5.Answer to question/submit finding for publication
Scientific Method Steps
1.objective/purpose of study
2.hypothesis
3.Methodology
4.Results
Gross Errors
human blunders \,resulting from performing a task not being very attentive to task at hand
Systematic Errors
consistly repeated when particular equipment is used
Random Errors
a natural part of measurement and can occur due to uncontrollable reasons. They can be caused by faulty equipment, fluctuations in the environment, or the operator’s interpretations.
Archelogical Site/Dig + Crime Scene Investigation(areas of simalarity)
1.Timing-time may be of the essence
2.Plan of attack for systematically searching the site to ensure nothing is left behind
3.Safety Issues-safety of scene searchers
4.Appropriate personnel-qualified, trained personnel to conduct search
5.Controlling the Scene-minimize contamination and lots of evidence
6.Documentation-record of scenes condition and evidence(chain of custody)
First Officers to Respond or at Crime Scene Steps
1.Ascertain whether perpatrator is still present
2.Tend to the injured
3.Call/notify the team and other personnel
4.Secure the Scene
Protocol At Crime Scene:Step 1:Preliminary scene examination by CSI
1.Further secure the scene
2.Look for a modus operandi
Modus Operandi
Pattern/method of operation that the criminally uses to commit crimes
Protocol At Crime Scene:Step 2:Systematic Search of Crime Scene
- Spiral Search
2.Line Search
3.Grid Search
4.Zone Search
Protocol At Crime Scene:Step 3:Record the Scene
1.Sketch-free hand sketch of the crime scene and notes
2.Later use computer programs
Protocol At Crime Scene:Step 4:Collection of Evidence
1.Contact of crime
2.Type of crime
3.Type of Crime scene(important in providing clues to what evidence should be present or collected
Protocol At Crime Scene:Step 5:Reconstruction of Crime
the process of determining the sequence of events that happened during and after a crime
Steps of Protocol at Crime Scene
1.Preliminary Scene Examination by CSI
2.Systematic Search of Crime Scene
3.Record the Scene
4.Collection of Evidence
5.Reconstruction of Crime
Microscope
An optical instrument that use a lens or a combination of lens to magnify and resolve details of an objects
Reason for Microscope Popularity
1.Sample Preperation is minimal
2.microscope can be used for identification
3.microscopy is non destructive to the specimen-minimum
4.Microscope is versatile
Microscope Versatility
-magnification power
-compare two specimens(side by side)
-add high resolution cameras for photographs
-Link microscope to another anylytical instrument
Comparison Microscope
compares 2 samples side by side
Compound Microscope
Max magniification power 450X of object,virtual image is inverted
Polarizing Microscope
polarize light:minerals metals/crystals
Stereomicroscope
image is upright,not inverted,scpace between stage and objective is greater
Microspectrophotometer
measures the intensity of wave lengths plots infrared absorption spectrum
Scanning electron microscope
a beam of electrons and measure electron emissions, high magnification(10x-100,00x),high resolution and depth focus
Evidence
anything that tends to prove or dispose something at issue
MUST HAVES for Evidence
-must be relevant, must be material that pertains to particular crime being investigated and not some previous incident
-must be probative(actually prove something-purpose
Classification of Evidence-Physcial Evidence
objects/things “touch free”
Classification of Evidence-Non Physical
feelings,emotions,what someone said,verbal testimony about a crime or someone action during a crime(1st hand memory of a witness-statements of arresting officer,statement made by the accused
Classification of evidence-Known Evidence
object whose source of ownership is known at time collected
Classification of evidence-Unknown Evidence
Evidence discovered elsewhere that has an unknown origin
Classification of evidence-Class Evidence
arise from several sources features shared by mutiple members of a certain group
Classification of evidence-Individual Evidence
Arise from one source features are unique to origin
Forensic Evidence Database Step 1
Integrated Automated Fingerprint Identification(IAFIS)
- FBI maintains
Forensic Evidence Database Step 2
Combined DNA index System(CoDIS) enables fed,state,local crime labs electronically exchange/compare DNA profile
Forensic Evidence Database Step 3
National Integrate Bullistics + Information Network(NIBIN) which allows firearms analysis to aquire digitize and compared marking made by firearms
-maintained by the Bureau of Alcohol Tobacco,Rirearms+Explosives(ATF)
Forensic Evidence Database Step 4
International Forensic Automotive Paint Data Query (PDQ) which contains chemical and odor info pertaining to original car paints
-maintained and developed by the Forensic Labatory Services of the Royal Canadian Mounted Police
