Criminal Investigation
The investigative process has the following four objectives 4
-establish that a crime was actually committed -identify and apprehend the suspects -recover stolen property -assist in the prosecution of the persons charged with the crime
The amount of time required to process a crime scene varies considerably, depending on such factors as (4)
-extent and nature of the area to be examined -complexity of the case -abundance or scarcity of physical evidence -available personnel
Trace Evidence Vacuums These systems are particularly effective in gathering: (3)
-hairs -fibers -certain types of drug evidence, such as cocaine
About 20% of AIDS patients developed raised, purplish colored lesions (kaposis Sarcoma) which may be present anywhere on the body. Most commonly, these are seen on the 3
-head -neck -oral cavitiy
In some investigations it is appropriate to withhold certain details about the crime scene from the media, such as (4)
-how a victim was mutilated -messages left at the scene by the perp -particular types of evidence -exact words spoken to a rape victim
To satisfy legal requirements related to its introduction in a judicial proceeding, investigators must be able to : 6
-identify each item of evidence they collecgted or handled -describe the location and condition of the evidence at the time it was collected -state who had contact with or handled the evidence -state when or during what time periods the eivdnce was handled -declare under what circumstances, and why, the evidence was handled -explain what changes, if any, were made to the evidence
Pollen comes in a variety of shapes and sizes. In order to be useful, analysis must not only present correlatioin from the crime scene to the suspect (as in the preceding case), but also,
-identify type -variety
What are the advantages of using a digital camera to document the crime scene
-images can be immediately viewed -can be printed on site -images can be quickly transmitted and disseminated
rules for the Crime Scene Investigator Regardless of the type of crime involved five fundemental rules must be observed: (5)
-maintain control -conceptualize events -proceed with caution -apply inclusiveness -maintain documentation
HIV The greatest danger to officers arises when they are (3)
-making arrests -seizing drug related evidence -processing crime scenes and accidents where blood and other bodily fluids are exposed
Fibers are of greater value as evidence than are rootless hairs because they incorporate such variables as (8)
-material type -number of fibers per strand -number of strand -thickness of fibers and strand -amouint and direction of twists -dye content -type of weave -possible presence of foreign matter embedded in them
Be cautious when conducting all types of searches; never put your hands anywhere you cannot see. Instead use: (4)
-mirror -probe with a flashlight or -wooden dowel -metal rod
In general the method of transmitting evidence is determined by 2
-nature of the evidence -urgency of getting an analyst's conclusion
The work at the crime scene is divided into three major functions (3)
-overall coordination of the scene -technical services -investigative services
sketches typically employ one of four different views
-overhead or birds eye view which is the most common -elevation view which shows heights -cross projection view which lays the walls to a room down so objects of interest in the wall can be mapped -less commonly, three dimensional view of the scene which can be crated using sophisticated software to form virtual views of the scene
The purpose of the crime scene search is to obtain 4
-physical evidence -identify the method of operation employed by the perpetrator -reduce the number of suspects -identify the perpetrator
When suspects have been interviewed but not arrested, their identities should not be disclosed. It is appropriate for the crime scene coordinator to generally describe to reporters the:
-physical evidence found at the scene -proceeds of the crime -weapons -issuance and service of search warrants
Even when the same type of criminal offense has been committed, the variation among crime scenes may be enormous. These variations are due to such factors as (3)
-physical settings -manner and means that the perpetrators used to execute the offenses -length to which they may have gone to eliminate or destroy evidence
Historically, these entities have been responsible for finding underwater evidence, such as weapons, safes, and vehicles, and locating and extracting the bodies of victims of crimes or those who have accidentally drowned. More recently, such units have been used to help (2)
-provide VIP protection -conduct security sweeps of high risk targets
Crime scene investigation is purposeful behavior and is intended to accomplish the following nine objectives: (9)
-reconstruct what happened -determine the sequence of events -find out what the suspect did or didn't do -establish the modus operandi -Determine what property was stolen and what articles were left by the suspect -reveal the motive -locate and interview witnesses -document and recover physical evidence -provide investigative leads
Paint is examined in several ways in the laboratory. Factors of importance in ints identification are (5)
-shade -composition -number of coats -texture -weathering
There are five basic crime scene search patterns from which the crime scene coordinator may choose
-spiral -strip line -grid -zone quadrant -pie/wheel
What are the three types of known samples?
-standard or reference sample -control or blank sample -elimination sample
what are the dis advantages of using a digital camera to document the crime scene
-stored images are subject to electromagnetic degrading -storage media can be obtained only at special stores -because the technology continues to evolve rapidly, accessing older archived images may not be possible with newer equipment
Although it is ordinarily class characteristic evidence, glass has high evidentiary value because if its (3)
-variation in density -refractive index -light dispersion characteristics
Three major methods of documenting crime scenes
-videotaping -photographing -sketching
What are the three types of un known or questioned samples?
1-recovered crime scene sample whose source is in question 2-questioned evidence that may been transferred to an offender during the commission of a crime and been taken away by him or her 3-evidence from an unknown or questioned source that can be used to link multiple offenses
Firearms Identification It includes identification of 4
1-types of ammo 2-knowledge of the design and functioning of firearms 3-restoration of obliterated serial numbers on weapons 4-estimation of the distance between a guns muzzle and a victim when the weapon is fired
There are three major scientific systems for personal indientification of criminals in wide use:
Anthropometry (relatively short lived) dactylophgraphy deoxyribonucleic acid (DNA typing)
Chapter 4 Characteristics of physical evidence that are common to a group of objects or persons are termed: An individual identification cannot be made because there is a possibility of more than one source for the evidence
Class Characteristics
The most important skill o the investigator is the ability to
Converse equally well with a wide range of people (this is essential becasue much of what we learn during an investigation come from people)
This reasoning creates a hypothesis about the crime. The explanation is tested against the factual situation
Deductive reasoning
Plaster of Paris is no longer recommended for use in casting impressions._____ is the preferred medium because of its greater strength, quicker setting time, ease of use, and because it provides more detailed impressions
Dental Stone
This is the most common serious disease in the world and is the leading cause of liver cancer? It is much more potent than HIV so officers are more likely to contract it in the absence of precautions
Hepatitis B (HBV)
This reasoning moves from the specific details to a general view. It uses the factual situation of a case to form a unified and logically consistent explanation of the crime
Inductive reasoning
Ingredients of Arrest There are three essential ingredients of an arrest (3)
Intention Authority Custody
The fundamental assumption on which crime scene searches rest is the _____: there is something to be found
Locards' Principle
This scene is the large view. It includes things such as the relevant locations, the victims and the suspects bodies cars and buildings
Macroscopic
This law changes much more rapidly than does the substantive criminal law. It deals with processes of arrest, search and seizure, interrogations, confessions, admissiblitiy of evidence and testifying in court.
Procedural Law
These glass fractures extend from the point of impact
Radial cracks
This relates to imperfections within a sample of non homogenous layers of flat glass
Ream
This dictates that every available piece of evidence be obtained and, where there is a question as to whether a particular item constitutes evidence, be defined as such.
Rule of Inclusiveness
Criminal incidents may have more than one crime scene. The primary scene is the locations where the initial offense was committed: the locations of all other subsequent connected events are:
Secondary scenes
This search involved the demarcation of a series of lanes down which one or more persons proceed. Upon reaching the starting point the searchers proceed down their respective lanes reverse their direction and continue in this fashion until the area has been thoroughly examined
Strip Search
Photographs of known offenders arranged by criminal specialty and height was known as?
The Rogues gallery
The most important incident to advance the use of fingerprints in this country was:
The West Case
The form and contents (of fill in the blank warrants) usually include
The authority under which the warrant is issued (name and state) Person who is to execute the warrant (generally addressed to any peace officer of the state) Identity of the person to be arrested designation of the offense date time and place of the occurrence name of the victim description of the offense and how it occured
The contributions of physical evidence to an investigation are diminished primarily by:
The inability unwillingness or failure to locate properly collect mark and preserve the evidence and by the drawing of improper conclusions of its analysis
The arrest of a news media worker at a crime scene should be made only upon:
The most serious provocation and with full awareness of the adverse publicity that is certain to follow for the police department
The first step in casting is
The preparation of the impression
The identification and location of the suspect are the goals of this evidence: corpus delicti and associative evidence may also serve these purposes
Tracing evidence
These are rib-shaped marks with a wavelike pattern on glass fracture edges that are almost always concave in the direction from which the crack occurred
Wallner Lines
In glass this is a line or crack surface fractures that run parallel to the direction of the crack
a Hackle
a cold lamp filament that receives a strong shock will break (often shatter into small pieces) without strecthing this is referred to as:
a brittle break or cold shock deformation
Crime Mapping Methods This is an excellent tool, to use when there is a large outdoor scene with no significant feartures or landmarks.
a grid system
When a hot lamp filament receives shock it will stretch and deform. This is refered to as
a hot shock deformation
Occasionally, it may be necessary to suspend an operation temporarily. One of the most common situations when this occurs is;
a priority crime with evidence subject to decay requires that the temporary diversion of personnel from a scene where delayed processing will not result in any loss of physical evidence
This is a measuring device that can be used at both indoor and outdoor scenes; initially, it found its way into law enforcement in the early to mid 1900's for use in traffic accident investigation and reconstruction
a total station
What type of log is responsibility of the crime scene coordinator and things such as who is assigned to what function at the crime scene and the sequence of events at the scene, including its release?
administrative log
News media personnel may photograph or report:
anything that they observe while legally at a crime scene or covering any other incident involving the police
This evidence is bidirectional in that it connects the perpetrator to the scene or victim, or connects the scene or victim to the suspect
associative evidence
Paint is transfered as fresh smears, dried chips or "chalking" from old dry paint. Cases in which such transfers occur include
burblaries hit and runs
By comparing ____, ____, and ____ soil examinations can determine whether soils share a common origin
color texture composition
These are glass fractures that form an approximate circular or oval pattern around the point of impact
concentric cracks
These glass fractures are funnel shaped or cause deep bevels in damage caused by a high velocity impact
cone or crater (hertzain cone)
What is still the primary means of capturing crime scene images
conventional silver based film used in a 35 millimeter camera
Each criminal offense contains a distinct set of elements whose commission or omission must be demonstrated to have in order to prove a case_____ substantiates these elements
corpus delecti evidence
This type of sample is taken from a source known to have has lawful access to the crime scene (such as a police officer, medical technician or occupant)
elimination sample
Choice of Mapping methods: This mapping method is the best to use with scenes having clear and specific boundaries, such as interior walls
rectangular coordinates
Footwear prints are formed when the soles are contaminated with foreign matter such as blood or dust and leave a print on a firm base, such as a floor, a chair, paper or cloth. Such prints are called:
residue prints
There are several methods by which footwear prints can be recovered. The best approach is to
send the original evidence to the lab
The guidelines for collecting pollen evidence are consistent with those for what other type of evidence
soil evidence
In actual practice, both the ___ and the ___search patterns are rarely used
spiral and pie
corpus delicti
the basic element or fact of a crime, as, in murder, the death of the murdered person
From 1961-1966 the supreme court became unusually active in hearing cases involving the rights of criminal suspects and defendants. ITs decisions focused on the two vital areas of search and seizure and the right to legal representation. This period was known as:
the due process revolution
Choice of Mapping Methods: When you are mapping outdoor scenes at which evidence is scattered over a fairly large open area, this method is an effective tool; it is not useful at scenes where the line of sight is limited
the polar coordinates method
Choice of Mapping Methods: This is useful both for interior scenes in buildings as well as for outdoor scenes, where measurement must spring from distinct "permanent" features or landmarks, such as the corner of a home, telephone, mailbox lighting poles, fences, stop sign posts, the intersections of paved driveways and roads, and other similar features
triangulation method
The FBI only accepts evidence for analysis which is related to a ___ from state and local law enforcement agencies
violent crime
The essence of packaging any evidence is to do it in a way that
will make any tampering with it clearly evident
When the crime scene is of significant size, this search pattern is normally employed
zone
This search requires that an area be divided into four large quadrants, each of which is then examined using any of the methods already described
zone/quadrant
This scene consists of the specific objects and pieces of evidence that are associated with the commission of the crime, including knives, bite marks, hairs and fibers, shoe and tire impressions, cigar butts, blood and so on
microscopic
Glass is imprtant as physical evidence because
of the frequency with which it is encountered
This evidence is generally created by the contact of two surfaces persons vehicles or objects, that results in the formation of compressions, imprints or markings
pattern
The decision to release a scene must be well thought out. An absolute must is to
photograph the scene again just before it is turned over to the responsible party.
This search entails dividing the area into a number of pie-shaped sections usually six. These are then searched, usually through a variation of the strip method
pie/wheel
In assessing the scene, use all of your senses: look, listen smell. Be alert for 3
possibility that violence is still on going dangers fro ordinary people dangers from special hazards
this is a software package that classifies archives and identifies shoeprints
(SICAR) Shoeprint Image Capture and Retrieval System
There are three types of crime scene reconstruction (3)
-accident or transportation oriented reconstruction -specific crime reconstruction -shooting reconstruction
Four major considerations dominate the crime scene search
-boundary determination -choice of search pattern -instruction of personnel -coordination
For submission to the laboratory, wrap the cast in (3)
-clean paper -bubble wrap -paper bags
Types Of Evidence There are three broad categories of evidence in which investigators have a particular interest (3)
-corpus delicti -associative -tracing
Evidence submitted to a crime laboratory is most often transmitted by: 3 IN the ideal situation, the investigator most knowledgeable about the case takes it to the laboratory
-courier -air express -registered mail
Documentation of the crime scene is a constant activity, starting with the rough, shorthand record created by field notes. Other types of documentation that need to be maintained include(10)
-crime scene entry log -administrative log -assignment sheets -incidence offense reports -photographic logs -rough sketch -evidence recovery log -emergency medical personnel documents -lifted prints log -consent search form or search warrant
Chapter 1 and 2 During the 18th century two events began a process of change that profoundly affected how police services were delivered and investigaitons conducted. What were the two events?
1-agricultural revolution and 2-industrial revolution
One or more plainclothes investigators may also come to the scene, depending on the severity of the crime. If they do, the first responding officer has teh following creim scene turnover responsiblities
1-breifing personnel taking charge 2-assisting in controlling the scene 3-turning over responsiblitiy for starting another crime scene entry log and 4-remaining at the scene until relieved
Staged crime investigations profit from a five step logical process
1-conduct a comprehensive and thorough review of the documented scene, which may be very time consuming in violent crimes because of the abundance of evidence 2-carefully consider the victims character, lifestyle, personal and professional associates, drug and alcohol use, normal hangouts, daily schedule and routines, physical condition, occupation, prior complaints to the police and recent conversations with neighbors and friends 3-identify and document in detail all possible indicators of staging 4-identify and document possible motives for the origial act and for the staging 5-Determine who benefits from the original act and the staging. even in death cases the deceased may benefit: suicide and insurance policy
The public thinks success is when the perpetrator is arrested and convicted. However, police consider success in two additional ways
1-exceptionally cleared, meaning the police can demonstrate who committed the crime, but for any over several reasons cannot pursue the case further 2-cleared by arrest, meaning that the perpetrator has been arrested and there is sufficient evidence to file criminal charges against him/her.
Chapter 3 When officials fail to prevent or cannot deal effectively with crime, there are negative consequences 4
1-future illegal acts are encouraged 2-resources that could be devoted to other social problems are diverted to deal with rising crime 3-public confidence in government faces a crisis 4-it tears the fabric of social relations and living patterns
criminalistics draws from diverse disciplines to study physical evidence related to crime such as (5)
1-geoloty 2-physics 3-chemistry 4-biology 5-mathematics
Normally the preliminary investigaiton is conducted by a uniformed officer from the Patrol Division and consists of the following six steps 6
1-receipt of info, initial response, officer safety procedures 2-emergency care 3-secure and control persons at the scene 4-issue a be on the lookout 5-evidence procedures generally 6-incident offense report
If splashed in the eyes or on mucous membranes (inside nose) flush the area for ____ using water, sterile water or a saline solution
15 minutes
Dental Stone sets fairly rapidly. In warm weather, it can be moved in how many minutes
20-30 minutes
Bites, needle sticks, cuts or similar incidents involving broken or punctured skin, however slight, should be washed immediately with soap in warm water for at least _____ and treated medically. Use soap from a dispenser not a bar.
30 seconds
Even the slightest opening in the skin can be a portal through which HIV enters the body. Protect skin wounds, abrasions, and openings with this:
360-degree fluid proof bandages
The use of gloves may reduce the amount of blood transferred by an accidental stick by ____ percent
50%
These devices use static electricity to attract dust particles of the print onto a dark colored lift film
electrostatic device
glass should be packed in a rigid, leak proof container such as ___ or a ____ paper and glass containers should not be used
film canister/plastic pill bottle
These occur when the footwear treads in some moldable material, such as earth, clay and snow
footwear impressions
If the fragments are sufficiently large to allow for a ____, glass may assume individuality.
fracture match
A variation of the strip search is the ___; After completing the strip pattern, the searchers double back perpendicularly across the area being examined
grid
Evidence with ____ can be identified with a high degree of probability as originating with a particular person or source
individual characteristics
The most important protective barrier against HIV infection is
intact skin
Infectious diseases The approximate risk of HIV infection after an accidental needle stick is _____
less than one percent