Flashcards in Criminal Inv-Chapter 3, Crime Scene Deck (57):
Criminal investigation is
a lawful search for people and things useful in reconstruction an illegal act or omission and analysis of the mental state accompanying it.
objective of a criminal investigation is
to determine truth as far as it can be discovered in any inquirey
successful investigations are based upon
fidelity, accuracy and sincerity
successful management of a crime scene involved three major functions
1. render crime scene safe and control movement of persons and officers into and out of area
2.crime scene investigators who conduct the search for evidence and also preparer the proper documentation of the crime scene
3. search for witnesses
first responders responsibiliity
neutralize the crime scene- making it safe, arrest of suspects, elimination of any hazards
when witnesses discus the crime or overhear others talking about the crime scene, they tend to adopt some of this info as their own or alter their recollection to fit with those other witnesses.
getting basic suspect info out to the field officers in a timely manner is of critical importance
search for evidence starts with
effective protection of crime scene.
searcher be certain that nothing has been removed from or added to the scene since the arrival of responding officers
tinme-based log that documents when an officer enters and leaves the scene.
crime reporting has made up ___of all coverage in local television newcasts.
associates of this single officer often assist in locating evidence, but they do not disturb it or collect it. Goal is to limit the number of officer in possession of crime scene eveidence to the officer searching the scene.
When search covers a wide area, availablle officers are assigned into teams,
one member of each team serves as the single officer collecting evidence.
systematic searching methods
1. point-to-point-movement- following a chain of objects that arre obviously evidence,.
2. ever-widening circle-officer start at the focal point of the scene or center of security area and works outward by cicling in a clockwiswe direction until the fringes of the protected area are reached
3. ever-narrowing circle- reverse of an ever-widening circle, officer starts on outskirts
4. zone or grid search- plotted like a football field, working back and forth until field is covered. Grid search is started after the strip search covering the rightr angles to the previous search
support the search as a systematic examination of the scene.
search of deceased person is often assigned to
field rep of the coroners or medical examiners office.
prerequisite to successful searching is
ability to discover and recognize evidence
victim or method of operation of the offender
Locards exchange principle
suspects will bring items of evidence into the crime scene and will take items with them when they leave. This exchange of trace evidence involves such items of evidence as hairs, fibers,dirt, dust, blood, body fluids, skin cells, and other microscipic materials.
___of evidence is maintained by keeping it in its orgininal state
Evidence likely to be found at crime scenes and amendable to scientific analysis is divided into severn major groups
2 blood and body fluids
3.imprints or impressions
4. marks of tools used to gain access to locked
5. dust and dirt traces
6. questioned documents
7. misc trace or tranfer evidence, including hair, fibers, skin cells
Marking evidence serves to ___
Traditional marking of objects includes
investigators initials, date, report number.
Counterfeit money should have a ___
dual marking. name of person last in possession shoudl be signed across a corner of bill. scratch his initilas on a coin
chain of custody
continuity of possession. must be established when evidence is offered in court as an exhibit,
any deviation from standard procedures in processing physical evidence can affect
credibility and contribute t a reasonable suspicion in the minds of the triers of fact about the entire police investigation
evidence must be packaged to
avoid breakage, loss or contamination in transit
used for transporting evidence over short distances
evidence box or board
to obviate any allegation of cross-contamination
evidence that will undergo comparison analysis for possible relationship should be packaged in seperate containers. no we or soiled materials or boxes or bottles should be used. clean and dry containers, wrapping paper, corrugated paper, boxes and sealing tape basis safeguards for physical evidence in transport
using plastic envelopes and bags used to transport soil, debris, clothing that contain bloodstains, bacterial action contaminating the blood sampe becomes a strong possibility
use plastic containers with caution. To an unusual degree, they can act as greenhouses for the cultivation of mold that can destroy the integrity and identity of some types of evidence.
use only tubes or vials with stoppers for
blood sampless and swatches use to collect bloodstains and follow directions on these kits for refrigeration and other care
stain on a solid object than can be moved, such as firearm or other weapon, transport the object. if on clothing
wrap the garments seperately in paper, mark them an package them
charred wood, carpet and drapery from a fire scene
wrap in metal foil and sealed in an airtight container.
paper and rags or sold samples from a fire scene
sealed in the container in which they were found or placed in airtight bottles or cans. This prevents the fire accelerant and its residues from evaporating.
should not be transported until the investigator has made certain that the container is safe for a period of time equal to at least twice the likely transport time
food, body substances and fluids should be placed in
as many seperate moisture-proof bottles or containers as necessary to avoid any contamination of evidence.
food or other substances suspected of containing or known to contain poison should be plainly labeled as suspected
known samples of poison
microscopic traces, hairs, fibers should be sealed
in folded paper or placed in a clean sealed envelope or box of appropriate size
known standard of evidence or a control
identification of physical evidence and the finding of its origin. This individualization of evidence often requires that physical evidence collected at at crime scene be matched with a known standard of evidence.
transporting evidence to lab, to storage, to prosecutors office or courtroom is the responsibility of
investigator who found the evidence.
when food or physiological fluids or substances are collected ____ ____is a primary precaution
refrigeration without freezing will prevent
physical evidence sent to a lab must be accompanied by an informative report. must be on official letterhead of the law enforcement agency and contain following
1 name and address of agency
2. crime classification of case by type and grade of offense
3. case number of agency
4. copy of offense report
5. list of evidence
6. list of suggested scientific examinations
7. brief statement of the problems in case
8. name and address of investigator
shipped evidence to lab should be marked
evidence for examination and outside package written request for examination with notation Letter or Invoice indicating its location
crime scene sketches and photographs
usually are offered in evidence as exhibits that are more realistic than words or that can assist jurors in understanding the case. they must withstand the basic tests of relevancy and materiality.
early 1857 evidence was admitted as exhibits to clarify the verbal description of a medical witness in a Maine case
nonphotographic drawing of a doctor illustrating the appearance of blood as seen microscopically
place an time to obtain data for a preliminary investigative report are
at the crime scene during the initial investigation.
basic purpose of offense or crime report originates at the operational level
is to record and transmit information
__ __ photography provides a permanent record of the facts at the crime scene
photographing a crime scene serves two purposes
provides a pictorial representation of the appearance and position of object at scene
it serves as evidence to support the testimony of the investigator as to what he found at scene, its location, nature and condition
show the locale, the approach route, means of ingress to scene or its premises, view of scene from normal entrance
(10 to 20 ft) pinpoint a specific object of evidence or significant segment of the crime
recording evidence in position and detail-location, nature and condition
excellent for studying crimes in series to ascertain whether the locations of past crimes suggest a pattern of criminal behavior. excellent for locating outdoor crimes scenes or controlling search patterns
to prove the corpus delicti, the essential elements of crime, a ______photograph is needed
sectional photography reassures
the triers of fact that the entire surface of the item of evidence was examined