Criminal Investigation: Investigators, The Investigative Process, and The Crime Scene
Criminal Investigation: Investigators, The Investigative Process, and The Crime Scene
Criminal Investigation: Investigators, The Investigative Process, and The Crime Scene
TWO
eighth edition
WHAT IS A CRIME?
A crime is the commission or omission of any act, which is prohibited or required by the penal code of an organized political state, to which some punishment or sanction is attached. Classifications
Felony
Punishable by death or imprisonment for more than one year in a state prison.
Misdemeanor
Punishable by fine and/or imprisonment for up to one year in a local or county jail.
Infraction or Violation
Minor offenses punishable by a fine only.
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THE INVESTIGATOR
Someone who gathers, documents and evaluates evidence.
Strong professional training and experience Strong degree of self-discipline Uses legally approved & ethical methods Strong people skills Includes all evidence of innocence as well as guilt Uses systematic methods of inquiry Uses both inductive and deductive reasoning Compassionate, not calloused and cynical Has wide ranging contacts across many occupations Remains objective at all times Leaves nothing to chance during investigation
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FOLLOW-UP INVESTIGATION
Subsequent investigation
Contacting witnesses who left the scene Checking out suspect(s) alibi Gathering additional evidence from other locations Talk with informants Attempt to locate additional witnesses Evaluate evidence collected and laboratory results of tests Obtain search and/or arrest warrants Recover stolen property Confer with prosecutor
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CRIME SCENE
Location where the offense was committed
May include surrounding areas where evidence may be located Always start big . . . Its much easier to make it smaller than to expand it at a later time There may be more than one crime scene Macroscopic versus Microscopic scenes
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Technical services
Crime laboratory personnel & supervisors
Investigative services
Interviewing witnesses and victims Neighborhood canvass Suspect field interrogations
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CATEGORIES OF EVIDENCE
Corpus Delicti evidence
Evidence that helps to prove the elements of the crime(s)
Associative evidence
Evidence that connects the suspect to the scene and/or victim or connects the scene/victim to the suspect
It is bidirectional
Trace evidence
Small or microscopic evidence, or evidence in limited amounts
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CONCEPTUALIZATION
Keep known fact AND inferences in mind when processing scene
Facilitates reconstruction of the offense Identification of the modus operandi Identification of certain types of evidence Assists in establishing investigative direction
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CAUTION
Dont destroy evidence Make crime scene bigger than expected and shrink as necessary Dont overlook fruitful areas for exploration Do more than a cursory examination
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INCLUSIVENESS
Obtain every piece of evidence If not sure, take it as evidence until it is ruled out Do not dismiss items of possible evidence
Be careful of rationalization and fatigue
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DOCUMENTATION
Constant Activity
Starts with rough shorthand field notes Sketches Diagrams to scale
WAYS TO DOCUMENT A CRIME SCENE VISUALLY INCLUDE: Video taping Photographing Sketching
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THREATS TO INVESTIGATORS HEALTH AND SAFETY AT CRIME SCENES Insect bites HIV/AIDS Hepatitis B and C Tuberculosis
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The crime scene coordinator may choose from a variety of crime scene search patterns based upon the type and size of the crime scene.
(b) Strip/Line
(c) Grid
(d) Zone/Quadrant
(e) Pie/Wheel
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