The Crime Scene Objectives
1. Define forensic science.
 Forensics science is the application of _______________ to the criminal and civil
laws that are enforced by the criminal justice system.
 Another name for Forensic Science is _______________
 Arthur Conan Doyle, the author, is said to be the father of forensic science.
2. Describe the services of a typical comprehensive crime laboratory in
the criminal justice system.
 Physical Science Unit: Applies principles and techniques of chemistry, physics, and
geology to the identification and comparison of crime-scene evidence.
 Biology Unit: Identify and perform _______________
 Firearms Unit: Examines firearms, discharged bullets, cartridge cases, shotgun
shells, and other ammunition.
 Document Examination Unit: Analyzes paper and ink, indented writings,
obliterations, erasures, and burned or charred documents.
 Photography Unit: Examines and records physical evidence using digital imagery,
infrared, ultraviolet, and X-ray photography. Also prepares documents for the
courtroom.
 Toxicology Unit: Examines body fluids and organs for the presence of
_______________ or _______________.
 Latent Fingerprint Unit: Processes and examines fingerprints.
 Polygraph Unit: Administers lie detector tests on suspects.
 Voiceprint Analysis Unit: Analyzes telephoned threats or tape-recorded messages.
 Crime-Scene Investigation Unit: Dispatched unit to collect crime scene evidence
for other units.
 Forensic Pathology: Investigates sudden, unnatural, unexplained, or violent deaths
to determine cause of death...usually by autopsy. _______________ Mortis
(muscles stiffen for 24 hours), _______________ Mortis (blood settles to areas
closest to ground after death), and _______________ Mortis (body loses heat about
1-1.5ºF after death).
 Forensic Anthropology: Identification of skeletal remains.
 Forensic Entomology: Study of insects and their relation to criminal investigation.
 Forensic Psychiatry: Relation between human behavior and criminal activity.
 Forensic Odontology: Identification by teeth.
 Forensic Engineering: Failure of structures.
 Forensic Computer Analysis: Identification, collection, analysis of evidence
gathered from computers, cell phones, and other digital devices.
3. Compare and contrast the Frye and Daubert decisions relating to the
admissibility of scientific evidence in the courtroom.
 Frye: 1923, Polygraph. All scientific evidence must be “_______________” by the
scientific community. New techniques that are yet to be accepted are not allowed
in the court. If evidence is too technical for the average person, an expert witness
qualified by knowledge, skill, experience, training, or education may testify with
their opinion as long as their opinion is based upon sufficient facts, is based on
reliable principles and methods, and the witness had applied these principles to the
facts of the case.
 Daubert: 1993. The judge must decide on the admissibility and reliability of
scientific evidence in court. Based on whether the technique or theory can be
tested, has been subject to peer review, the error rate of technique, the existence
and maintenance of standards controlling the technique, and whether the
technique has widespread acceptance in the scientific community. The judge is the
“_______________” and may allow new techniques as long as they fit within the
appropriate standards.
4. Explain the steps taken to thoroughly record the crime scene.
 First officer arriving at scene musts _______________ the area, protecting and
preserving the evidence as much as possible.
 Obtain _______________ assistance for individuals in need
 _______________ any perpetrators at the scene
 _______________ all unauthorized personnel using ropes, tape, or barricades
 Evaluate evidence, documenting, sketching, and photographing in their unaltered
state
5. Describe proper techniques for packaging common types of physical
evidence.
 All evidence must be kept in its _______________ condition and intact
 Blood, hair, fibers, soil, and other trace evidence should not be _______________
from the objects they are on…with common sense.
 Package each item _______________
 Trace evidence is usually packaged in manila folders, screw-cap glass vials, or
pillboxes.
 Blood-stained garments and other clothing items are placed in paper to maintain
_______________ and prevent mold.
 Charred debris is placed in an airtight container to prevent evaporation of
petroleum residue
 All evidence must be tagged properly
 Collectors initials, date, description of item
6. Define and understand the concept of “chain of custody.”
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Also called continuity of possession
All transfers of evidence must be noted on the tag
All individuals who handle evidence may be asked to testify
Chain of custody should be kept to a _______________
7. Understand the implications of the Mincy and Tyler cases as they
relate to search warrants.
 Mincy: Police may not conduct a warrantless entries and searches unless they
deem that a victim is in _______________ need or if a _______________ is on the
premises.
 Tyler: Court ruled that entry to fight a fire can be done without a warrant, and
any evidence gathered while in the process of fighting the fire is admissible in
court. However, when _______________ and _______________ permit, a search
warrant must be obtained.