UNIT 2 THE FOUNDATIONS OF CRIME SCENE

INVESTIGATION

Overview

In unit one, you would have been previously exposed to the basic concepts in forensic

science, its history, the role and the function of the forensic scientist. Every discipline has

principles governing the delivery of what it is expected to convey. Therefore, the

principles should follow a pattern of investigation to enable the most suitable outcomes.

It stems from criminal investigation to appropriate crime scene investigations, to the

presentation of evidence in the law courts. This unit is geared towards allowing you to

identify the principles of forensic science and to have a better understanding of how these

principles function in this forensic science.

Unit Objectives

After completing this unit you should be able to:

1. Explain crime scene investigation

2. Assess various crime scenes

3. Explain the techniques in crime scene investigation

4. Describe the sociological and psychological techniques in crime scene investigation.

Readings Available:

Saferstein, R., 1998, Criminalistics: An Introduction to Forensic Science 6th

ed., Prentice

Hall NJ.

Session 2.1 What is Crime Scene Investigation

Learning Objectives

At the end of this session you should be able to:

1. Define crime scene investigation

2. Differentiate between primary secondary and microscopic crime scenes

3. Identify techniques in crime scene investigation

4. Explain what crime scene investigators do.

Introduction

Crime scene investigation is an exciting part of forensic investigation. It is absolutely

important for forensic scientists to be equipped with the necessary skills to conduct

thorough crime scene work and to be able to reach a scientific conclusion.

In this session, the crime scene and the crime scene investigator will be defined. The

sociological as well as the psychological aspects of crime scene investigation will also be

defined with particular interest in criminal profiling as a major psychological crime scene

technique. A complete understanding of the various interviewing methods and techniques

will be necessary in appreciating the crime scene.

What is crime scene investigation?

Crime scene investigation is a step by step process in which the forensic scientist

identifies, collects, examines, preserves, interprets, recognizes and reconstructs all

physical evidence in order to solve a crime. Forensic examination of physical evidence is

crucial and forms the basis of the scientific investigation. The physical evidence

distinguishes one suspect from another and is the most convincing form of proof. The

crime scene investigator collaborates with the forensic crime laboratory which examines

the physical evidence to provide investigators with the appropriate information regarding

the evidence in the attempt to solve cases. The crime scene investigator must be able to

use analysis skills, and various techniques, as well as be aware of the linkage principles

regarding the evidence that will allow him/her to be able to reconstruct the crime scene.

Crime scene investigation must therefore be properly managed and investigated in the

most appropriate manner.

Activity 2.1

Activity 2:2

Crime scene investigation is governed by a set of principles and

procedures.

Activity: What’s Your Definition?

Try outlining your personal definition of crime

scene investigation.

Activity: Create Your Crime Scene

Create a simple crime scene and post in the discussion

forum. View the following video for some ideas

http://www.youtube.com/watch?v=O2kkccZsewM

Create a crime scene and post in the discussion forum.

Discuss the crime scenes posted with your classmates.

What is a crime scene?

A crime scene can be classified as the site of the original or first criminal activity where

a crime took place. A crime scene can either be primary or secondary. Crime scenes are

inconsistent and no one single approach works in determining the ultimate crime scene.

The ultimate crime scene is a combination of different classifications that is determined

by the crime scene investigator. The crime scene investigator must be skilled at

evaluating and must frequently evaluate the area referred to as the crime scene. (Miller,

2003)

Primary crime scene - The primary crime scene is the place where the actual

offense took place1 and hence is the site of original activity.

Secondary crime scene - A secondary crime scene is the place in some way, shape,

or form, that is related to the offense but is not the place where the offense occurred2. A

secondary crime scene may therefore be any subsequent crime scenes associated with the

original scene of the crime.

In general, primary scenes hold more usable clues than do secondary scenes but not

always3. Sometimes, the only crime scene that crime scene investigators have to go on is

the secondary scene - the place in the woods where the perpetrator dumped the victim's

body. Under such circumstances, forensic investigators may not know the primary scene

where the killing occurred and therefore they may be forced to rely on the use the clues

found at the secondary scenes to help them establish the identity of the offender or locate

the primary crime scene.

1 Source: http://EzineArticles.com/932577

2 Source: http://EzineArticles.com/932577

3 Source: http://EzineArticles.com/932577

Microscopic Crime Scene: - This scene is composed of several scenes. The following is

a representation of many different crime scenes under microscopic review. A victim’s

body found dumped in a filed represents the several crime scenes within the overall crime

scene of the field: the body, the body’s wound, and the area around the body.

Other classifications of crime scenes are those based on the type of crime committed such

as; sexual assault, homicide or robbery.

Physical location: Crime scenes are also classified according to physical location. This

includes whether the crime scene is indoors, outdoors or via a vehicle.

Activity 2.3

Types of information obtained from the crime scene investigation.

1. Information on the Modus Operandi- This is a specific pattern of how the

offending criminal behaved. This identifies one criminal from another. Criminals

repeat their behaviour and a particular behaviour becomes a criminal’s signature

or a preferred way of carrying out crimes. For example burglars frequently gain

entry into scenes using the same techniques.

Activity: Crime Scene Information

1. Make a list of some of the important information an

investigator may collect from the crime scene.

2. Describe how a detailed analysis of a crime scene should be

conducted?

3.

2. Information on the Corpus Delicti- This is the determination of the relevant

facts of an investigation. This includes the physical evidence, the patterns of the

evidence as well as the laboratory examination of the evidence. The red stain in a

bathroom may be significant to an investigation, but may be extremely relevant if

the DNA matches that of the victim.

3. Linkage of Persons, Scenes, and Objects- The most imperative and common

type of linkage is the ability to link suspects to victims in any criminal

investigation. This can be accomplished by physical evidence in any case. In

addition, liking victims and suspects to objects and scenes can be accomplished

by the use of physical evidence.

What does crime scene investigation involve?

1. Identification of suspects: Identification of physical evidence is a procedure that

involves comparison testing. This can be achieved by fingerprint testing that identifies an

individual. Fingerprint evidence is the best example of comparison testing. The

identification of a suspect is accomplished by recognition, identification, and

individualization of the physical evidence that may point to that suspect. Additionally,

DNA data allows a single fingerprint or blood stain found at the crime scene to identify a

specific suspect.

Activit

Activity: All About Fingerprints

http://www.youtube.com/watch?v=0OL7hE2l_70

http://www.youtube.com/watch?v=R0e8WXkFA64

http://www.youtube.com/watch?v=iomWm3_Qvhk&feature=r

elated

http://www.youtube.com/watch?v=IrpTqKkgygA

2. Identification of unknown substances: This involves the identification of drugs,

poisons or any other substances.

3. Individualizing the evidence: This process involves the use of fingerprints to

distinguish one individual from another. A single finger print found at a crime scene or

even a small blood stain can identify a suspect.

Providing Investigative Leads: This is a very important process of crime scene

investigation. Leads such as physical evidence can assist the investigator in determining

specific details regarding a bag or footwear. The investigator must bear in mind that not

every crime scene has individualizing physical evidence for e.g fingerprints, but every

crime scene contains some form of physical evidence that helps the investigator. The

size, type and colour of a suspect bag, or shoe can easily be identified.

4. Reconstruction of a crime scene: This is the final step in the examination

process and it involves determining and eliminating the events that occurred at the

crime scene. The use of logic, interpretation, careful and naturalistic observation

and reasonable explanations are used. The cornerstone of reconstruction is to

incorporate physical evidence with trace evidence. Crime scene reconstruction

follows scientific principles such as hypothesis formulation, theory formulation,

and logical methodology. The use of logic, careful observation, preserving and

interpreting all data concerning the physical evidence, patterns and impressions of

the victim will be reviewed, organized and studied.

Activity 2.5

Activity 2.6

Summary

In this session you were introduced to various aspects of a crime scene. What constitutes

a crime scene including the physical location, the linkages to suspects and victims, the

importance of proving investigative leads as well as reconstructing the crime scene were

all highlighted. You should have a better appreciation of the necessary steps.

Activity: Think you can Reconstruct a Crime Scene!

Using the information provided below let’s try to recreate this crime

scene.

It’s June 25, 2011. There is a bedroom with a broken window pane. There is

the body of a female lying in the bed with a gunshot wound to the head. A gun

is in the victim’s hands and there is a blood stain on the pillow. There are two

glasses of unfinished wine on the side table

You may use diagrams and explanations to recreate your crime scene.

Share your recreation with your classmates and discuss the submissions

of others.

Activity: Crime Reconstruction Examples

http://www.youtube.com/watch?v=e3E2AMgDf5Y&feature=related

http://www.youtube.com/watch?v=QVzwa-DQRu4&feature=related

Session 2.2 Sociological and Psychological Foundations of Crime Scene

Investigation

Learning Objectives:

By the end of this session students should be able to:

1. Outline the sociological and psychological factors that affect crime scene

investigation

2. Appreciate the role of criminal profiling in crime investigation

3. Describe steps in the criminal profiling procedure

Introduction

The sociology of crime scene investigation raises questions about the relationship

between the individual and society, the nature of crime evidence and social justice.

This gives one an appreciation of how social patterns of behaviour can provide predictive

relevance and meaning in a social context. Therefore, in order for forensic scientists to

have a better understanding regarding crime scene investigation, they should seek to

understand the connection and similarities between sociology and crime scene

investigation.

The individual and society- the individual functions in a social context in society. Crime

is considered a social problem and is any act that violates criminal or civil law. If an

individual violates the in law in any manner, it can be considered a crime.

Social justice- victims of a crime as well as their relatives look to the criminal justice

system to render social justice after a crime has been committed. The forensic scientist

works in collaboration with the criminal justice system to bring perpetrators of crime to

justice in a fair and systematic manner. Social justice holds the view that everyone needs

to be protected under the rules of the law and should be able to conduct their business on

a daily basis without feeling threatened by anyone. If violated in any manner, the justice

system is in place to protect citizens accordingly.

Psychology of Crime Scene Investigation

Many students are fascinated about the field because of their desire to be like Clarice

Starling of The silence of the Lamb. The psychology of criminal activity is a fascinating

area of study and crime scene investigators often apply psychological analysis in order to

solve crimes. The ultimate goal of using psychological intervention is to be able to

understand how criminals think. Forensic scientists often scan the crime scene combing

for evidence that eventually leads to the offender. In order to effectively do this, a

criminal investigation must begin by examining the origins of profiling criminals. The

forensic scientist works in conjunction with the forensic psychologist to help profile

suspects and bring them to justice. Profiling of suspects is crucial to the understanding of

criminal activity. This entire process is called criminal profiling.

Criminal Profiling- this is the ability to outline physical and psychological qualities that

link criminal or deviant behaviour to a specific crime. It is an attempt to provide

information about a suspect. It consists of examining a biographical outline of

behavioural patterns, motivations, trends, tendencies type of weapons used,etc. Criminal

profiling is based on the premise that people behave according to their pattern at the time

of action.

Activity 2.7

Approaches to Criminal Profiling

Distinguishing the Evil Person

The profiler needs to understand the behaviour and motivations of the offender. One must

be able to predict the behaviour while persons play specific roles. For example a

prominent profiler indicated that Adolf Hitler’s childhood relationship with his parents

had a major impact on his later behaviour. Hitler witnessed his father being brutally cruel

to his wife and children causing them pain in the process. Therefore, Hitler’s approach to

adversity and human beings was the same.

Determining Common Characteristics

To determine common characteristics is to carefully examine consistencies in

personalities, backgrounds and behaviours of offenders who carry out similar offenses.

One may ask the following questions.

Are all rapists alike?

Are all murderers alike?

Activity: Criminal Profiling – A dramatization

http://www.youtube.com/watch?v=CMjIk-pRtYo

The Possible Reality! -When we miss the signs

http://www.youtube.com/watch?v=WA33rKJWwI8&feature=

related

This involves the process of crime classification a concept that was mentioned earlier in

this unit. Characteristics can be determined by assessing the childhood background of

suspects and looking for similar experiences. For example, in a research conducted by

(Sullivian & Sevilla,1993) the researchers discovered that out of 41 men, 31 of them

who had committed raped reported that they had been sexually abused as children.

Extracting Specific Characteristics

This is assessed by carefully looking at the Modus Operandi (MO). The Modus Operandi

is also referred as the “Standard Procedure” meaning the way how the suspect carries out

his/her crimes. The MO represents the signature of a person and this distinguishes one

suspect from another. The profiler must examine whether there are psychological or

physical characteristics that can be drawn from the crime scene to profile a suspect. The

profiler must also determine whether patterns of behavior; past or present; resemble

patterns from previous cases.

The signature- this reflects unique and personal aspects of the criminal act but this is

often seen in cases of sexual nature.

The Forensic Psychologist-

The forensic psychologist works closely with the forensic scientist and the criminal

justice system in a number of ways.

As a criminal profiler – They identify suspects and are able to link individuals

according to personality, sex, attributes and characteristics. It is the job of the

forensic psychologist to identify and examine the most common and prevalent

forms of these unique traits. They identify these characteristics based on specific

information regarding the victim as well as the method of criminal activity.

Persecution Process- Forensic psychologists also play a pivotal role throughout

the prosecution process. They provide testimony when suspects are on trial. They

testify as expert witnesses in court and as a reliable source on the validity of

forensic evaluations.

Psychological Assessment of Perpetrators- It is the job of the forensic

psychologist to assess perpetrators both in civil or criminal cases. The

psychologist is concerned with whether the offender was suffering from any

mental disease at the time of the criminal offense and if he/ she would be a threat

to society.

Psychological Techniques in Crime Scene Investigation

Crime Analysis- this focuses on the dynamics of the crime scene and this is another way

of profiling places and suspects. The profiler makes an educated guess based on past

experience. This is referred to as a hypothesis. This is an idea to explain an observation or

the result of an experiment. A major element of any hypothesis is that it must be testable.

A null hypothesis is often used in forensic science. In this approach, the forensic scientist

starts with a hypothesis that can be disproved. Meaning, if he/she is testing a blood

sample, the null hypothesis might be that the blood did not come from a potential suspect.

It is only a hypothesis at first, but by using comparative DNA testing the forensic

scientist will have the opportunity to prove/disprove the hypothesis.

The Criminal Profile Generating Process

This process is comprised of several steps:

1. A comprehensive study of the nature of the crime and the types of persons who

have committed similar offenses in the past.

2. A detailed analysis of the crime scene.

3. An in-depth examination of the background and activities of the victim or victims.

4. Formulations of motivating factors for all parties involve.

5. The development of a description of the potential perpetrator based on overt

characteristics from the crime scene and past criminals’ behaviour

(Wrightsman,2005)

Activity 2.8

Summary

In this session, defining the sociological and psychological aspects of crime scene

investigation is pivotal to understanding the behaviour of suspects and victims from a

sociological as well as a psychological perspective. Unique pertinent details can help

solve a case a bring perpetrators to justice.

Activity: Procedural Steps - A Discussion

Based on the five procedural steps outlined above:

Write a 300 word essay outlining the importance of each

step.

Also discuss how the omission of any one step may

jeopardize the investigation.

Session 2.3 Interviewing and Investigation Techniques

Learning Objectives:

By the end of this session students should be able to:

1. Differentiate between interviews and interrogations

2. Explain the interviewing and investigative techniques in crime scene

investigation.

3. List investigative skills needed by Forensic Scientists

4. Outline various methods of interrogation

Introduction

Techniques in criminal investigation are used to help forensic personnel fit pieces of

evidence/information together. To this end various types of interviews and interrogation

techniques are available to forensic personnel, e.g verbal and non-verbal communication

as well as observation. Additionally forensic personnel must also take into consideration

the type of questions used, or whether inappropriate use of force was utilized. The

concept of false confessions, detecting deception and other forms of manipulations are

areas of concern. Interviewing the victim and the suspect, examining the offender’s

statement, and looking at vulnerable witnesses are all necessary throughout this process.

First Responders.

The first responders at a crime scene are usually police officers, fire department

personnel and other emergency personnel. They are the ones to come into contact with

the crime scene first and are usually the ones to view it in its original state. These

individuals begin the process and their actions at the crime scene provide the basis for a

successful or unsuccessful investigation. They must always keep in mind that the process

begins with them and that they begin the process that links victims to suspects. The first

responders must always maintain an unbiased approach.

Development of investigative skills:

The following skills are necessary in carrying out investigative work for all forensic

personnel:

Objectivity: professional and personal responsibility; self-monitoring;

moral and ethical behaviour; respect and impartiality must always be part of this process.

Communication: Both verbal and nonverbal communication skills are important as well

as being attuned to cultural/social differences. Forensic personnel also need to develop

effective listening skills

Interpersonal Skills: Effecting and maintaining adequate social and relationship skills;

dealing with conflict and ambiguity; ethical use of investigative powers; developing

accurate written and verbal presentation skills; and the appropriate demeanour when

giving evidence in court.

Assessment skills: Assessing the situation; accurate and ethical recording of crime and

potential sources of material for evidential value; collation and analysis of information;

developing and testing hypotheses; identifying links and drawing conclusions;

interpreting evidence; writing accurate reports/papers

Questioning

Most questioning and investigation is done by the crime scene technician or investigator

who is referred to as the forensic specialist. The technician is someone who analyzes and

obtains evidence at the crime scene and reports the findings to the relevant authorities.

The technician questions possible suspects and all those who may be associated with the

criminal offense.

Interview vs. Interrogation

Interview

The difference between an interview and an interrogation is that an interview is

conducted in a cordial atmosphere where a witness is more comfortable physically and

psychologically. On the other hand, whenever a person is questioned in an uncomfortable

atmosphere (interrogation room) where he/she is under any psychological pressure, it is

an interrogation. The interrogator, in this case, has more psychological advantage than

his/her suspect. Interrogation is a kind of psychological warfare between interrogator and

suspect. Only when an interrogator overpowers a suspect psychologically, the

interrogator may get a confession, or the facts of a case which may not have been

previously revealed.

Activity 2. 9

Activity: Develop Your Interviewing skills

These videos may help you develop the skill you need!

http://www.youtube.com/watch?v=Zt_rnt7wbbI&feature=related

Can you easily detect a lie, or spot a liar?

http://www.youtube.com/watch?v=SbH781mVa4E&feature=related

http://www.youtube.com/watch?v=CAHUTNTCaSU&feature=related

http://www.youtube.com/watch?v=E3PAW7zjgPw&NR=1&feature=fvwp

Interrogation

Interrogation is an art. Every good investigator is not necessarily a good interrogator. To

be a good interrogator you need to be a good actor and must have an insight of human

psychology. You also need to be able to apply psychological principles during and after

the interrogation process. Your approach should be different according to the age,

profession and intellect of the suspect because your suspect could be a lawyer, doctor,

scientist, professor, manager or an unskilled laborer. Interrogation techniques are also

affected by the age bracket of the suspect, the suspect could be a child, teenager, adult or

senior citizen.

Prerequisites of an Interrogation:

The following information is necessary when conducting an interrogation:

About the Suspect:

(I) Name, age, profession, occupation of the suspect

(2) Social and financial situation

(3) Criminal history

(4) Relationship with the victim if any

About the Victim:

(1) Name, age, profession, occupation

(2) Social and financial situation

(3) Criminal history if any

Scene of crime:

(1) Time and place of occurrence

(2) Modus operandi

(3 Physical evidence collected

(4) Information collected

Approach

Appropriate places for interrogation:

(a) At the spot when a suspect is apprehended at the scene of the crime

(b) In an interrogation room where the interrogator has more psychological

advantage.

Appropriate time for interrogation:

As soon as the suspect is apprehended and information collected

You should always remember that a suspect is innocent and not a criminal unless

guilt is proved in court.

Don't ever use third degree method.

Always maintain courtesy.

Be a good listener.

Control your anger because in anger you loose reasoning and the judgment made

without reasoning is mostly incorrect.

Never be in a hurry to finish the interrogation.

Methods of Interrogation

We can classify criminals into two major categories:

emotional offenders

non-emotional offenders

The purpose of classification is to vary your approach and methods during the

interrogation of a suspect.

Interrogation of emotional offender:

Interrogation of an emotional offender is much easier than of a non-emotional offender.

An emotional offender is usually a first time offender who can be broken down easily if

the investigator understands how to manipulate the offender’s emotions, of love, hatred,

anger or frustration. This can be achieved by:

By showing sympathy towards the offender.

By telling the offender that anybody would do what he/she has done if placed in a

similar situation.

Blaming the society for the offender’s action.

Being friendly with the offender and offering him/her food or a beverage,

something which an offender never expects from an investigator.

By the investigator keenly observing the offender’s physical reaction and

nonverbal communication to the crime related and non-crime related questions.

When an individual is lying he/she may be under tension. The anti-diuretic bio-

chemical substance released by his/her body leads to the dryness of his/her mouth

and lips. Again, in tense situation an individual may tap his/her foot, play with

his/her fingers, look blankly somewhere else, other than at the investigator. All

these can also be expressed forms of anxiety.

Emotional offenders easily confess when confronted by the evidence that is clear

and compelling.

Interrogation of non-emotional offenders:

Non-emotional offenders are usually hardened criminals. They are professionals who

have probably gained experience committing a series of crimes and either subsequently

have evaded apprehension, or have served many jail terms. They don't like to talk much if

at all. So it’s usually difficult to engage them in conversation for any length of time.

There are several interrogation methods from which an investigator can choose:

Question and Answer Method: This is a common form of interrogation where an

interrogator asks several questions to get the facts of a case. He/she develops his/her

questions based on the facts of the case and the answers given to him/her by the

suspect.

Narrative Method: Always be willing to listen to the suspect. Let the suspect tell his

/her side of story without interruption. Ask him/her to repeat it several times may be

three or four times. He/She maybe have to tell more and more lies just to cover up

one lie. The more he/she lies, the more you have a chance to detect untruthfulness of

the story. Verify his/her story and re-interrogate.

Alibi: Ask probing questions and allow the suspect to speak .Ask where he/she was

and what he/she was doing at the time of occurrence of the crime. Verify his/her alibi

and re-interrogate him.

Factual method: Some criminals are smart and sometimes more than one approach

is needed in order to get information from them. The best way to interrogate a

hardened and professional criminal is to confront the person with the physical and

circumstantial evidence. This may which will eventually lead to a confession by the

suspect.

Sweet and sour method: The use of two interrogators with different styles is

sometimes essential in an investigation. Interrogations conducted by two different

interrogators, one being soft spoken and other being harsh towards the suspect could

be fruitful in some cases.

Overheard conversation method: different approaches wok for different

suspects. Whenever there is more than one offender this method works well. One

suspect while being interrogated should be viewed, but not heard,by the other suspect

from outside of the interrogation room. When the suspect who was allowed to view

turn for interrogation starts, tell the offender that his/her associate has already

confessed about the crime and now it is his/her turn to confess.

Hypothetical situation: Allow a suspect to suggest, even if he/she has not

committed the crime, how would he have done it in the similar situation. Maybe some

important clue could come out of this.

Telling the story backward: Sometimes it is important to ask a suspect to reveal

his/her side of the story from the day before in order to view things from a different

perspective. If he/she has told you what he/she has been doing from the day before

5AM to the present day spanning a period of more than 12 – 15 hours. Then let the

suspect start from the ending period and work backward to the beginning time.

There is no hard and fast rule as to what method you apply to extract the facts or

the confession. It is up to you and, your experience will guide you when

interrogating various kind of suspects. But one should always keep in mind that a

confession, even in writing, is nothing more than a piece of paper unless it is

supported or corroborated by other independent physical or circumstantial

evidence.

Activity 2.10

Activity: Sweet and Sour Method

Watch this scenario

http://www.youtube.com/watch?v=NmO-

a_93bPs&feature=related

Now write your thoughts on the good guy- bad

guy interrogation process.

Post your thoughts in the discussion forum and

react to the thoughts of your classmates

Interviewing of Witnesses

There are various kinds of witnesses such as:

indifference witness

interested witness

hostile witness and

child witness.

An indifference witness is the best kind of witness for a case because the witness does not

have any interest in success or failure of the case. He/She will always prefer to tell

whatever is known about the case without lying, whereas the interested witness may be a

friend, a relative or a potential beneficiary in the case and may embellish aspects of the

occurrence. As for the hostile witness, he/she may have close relationship or friendship

with the suspect and may want to lie to protect the suspect. You may need to interrogate

rather than interview a hostile witness. Most children are volatile witnesses who do not

lie but are vulnerable to the suggestions of others.

It is worthwhile to have an eyewitness to support a case but you should also recognize

that education level, technical knowledge, physical condition, profession and emotions

variables that will impact the eye witnesses’ observation. Don't expect to get one

hundred percent of what happened when the incident took place. An eyewitness may not

observe as keenly as a police officer or other trained investigator would observe.

However, an eyewitness’ information is valuable if it corroborates with the physical or

circumstantial evidence collected. Reconstruction of a case is often important to verify

the truthfulness of the information of an eyewitness.

Activity 2.11

Psychological Autopsy

Psychological autopsy refers to a investigative method used to help determine the mode

of death in equivocal cases. The idea is to find out how the death occurred. It is geared at

finding out whether a death was an accident or a suicide. This is a designed instrument

with 16 items designed to assist the medical examiner. It list 16 behavioural descriptions.

Each item is checked off and the results indicate whether the death was accidental or

suicidal.

Lie Detection/ Use of Polygraph

Police often use various devices to question suspects. The polygraph technique also

referred to as the lie detector has often been used for assessing the honesty of statements

of criminal suspects and to detect lies. The Polygraph measures changes in the suspect’s

body associated with stress of deception – minute changes in alterations in heart rate,

breathing, emotional distress and increase in perspiration. Please be aware that some

persons possess knowledge of how to beat the polygraph test.

Activity 2:12

Activity: Eyewitness

Are you a g reliable eyewitness?

http://www.youtube.com/watch?v=rSzPn9rsPcY

http://www.youtube.com/watch?v=ynpBirT8Nb4&feature=r

elated

http://www.youtube.com/watch?v=bueSHtqk1jM&NR=1

Activity: Polygraph vs. Body Language

Which is more reliable?

Watch the videos

http://www.youtube.com/watch?v=pqjMhNGyDyQ&feature=related

http://www.youtube.com/watch?v=tJXMrJJMNZ4&feature=related

Computerized Voice Stress Analyzer

Computerized Voice Stress Analyzers measure changes in voice frequency in the human

voice that occurs whenever someone is lying. The use of this tool is helpful to an

investigator in order to narrow down the area of investigation even though the results are

not admissible in a court of law due to the probability of evading a deception. However,

when used along with a polygraph test the results can be considered more accurate

Activity 2:13

Summary

In this session you were given the opportunity to be exposed to different types of

interviewing and interrogation techniques. You should find it useful to incorporate all

these important techniques as a forensic scientist.

Activity: Voice Stress Analyzer

Let’s view how it works

http://www.youtube.com/watch?v=uRmVgFWbP6k

Session 2.4 Characteristic in Crime Scene Investigation

Introduction

Like any other skilled profession, the forensic scientist must be skilled as well as

educated in his field of study in order to carry out forensic work effectively. In order to

achieve this, physical characteristics must be paramount. The goal of the crime scene

investigator is to understand how crime scene investigation works and to be skillful in

applying the appropriate techniques and characteristics.

Learning Objectives:

By the end of this session students should be able to:

Discuss the techniques and characteristics in crime scene investigation

The crime scene investigator must be able to endure, use manual dexterity as well as

fortitude.

Endurance: This is absolutely important because forensic work takes time. Not all

crimes can be solved in the same time and depending on the nature of the crime, many

hours are spent putting pieces together much in the same manner as one spends much

time on a gig-saw puzzle.

Manual Dexterity: investigators must be able to use equipment and other aspects of

forensic work properly. Their ability to manage the crime scene is of vital importance to

every case.

Fortitude: crime scene investigators will be exposed to murders, sexual crimes, deviant

acts and things that may make them both physically and psychologically ill. Sometimes

the crime can be heinous and can create some difficulty accepting and staying in course.

A person's ability to accept what happened and to move through it to get the job done is a

quality that is greatly needed to get the job done effectively and efficiently.

The characteristics in crime scene investigation are being able to manage the crime scene

effectively. Crimes today are solved by teamwork of investigators and by large crime

scene personnel using a combination of techniques and procedures to determine evidence,

records and procedures pertinent to the crime being investigated. The crime scene

management entails information management, manpower management, technology

management and logistics management.

Information management- This is the process of gathering and securing important

information relevant to the crime investigation.

Manpower management- This is the process of using all forensic personnel and

determining the most suitable according to the nature of the criminal activity.

Technology management- This is the use of the most appropriate special technology

that must be employed.

Logistics management- This is the ability to work out the fine and pertinent details

regarding the criminal investigation and to rule out information that is not important.

Crime Scene Recognition – The goal of the crime scene recognition stage is to gain an

understanding of the details of the crime scene and to derive a systematic approach to

finding and collecting evidence. The first step is to decide on the extent of the crime

scene. Determine whether the crime is a homicide, suicide, or accident. Assess whether

one victim is involved, or a number of victims and whether blood stains or a trail is

present. The investigator must be vigilant and assess whether blood stains or other fluids

leave a trail in other areas. If this is the case, the crime scene might be the entire

neighborhood.

Securing the crime scene- The idea of securing the crime scene is to be able to link

physical evidence from or to the victim, suspect or crime scene. It is absolutely crucial to

keep unauthorized persons away from the crime scene because anyone entering a crime

scene can alter or change the scene and its evidence. Block off the core crime scene area

for preservation of evidence and current and future investigation.

Crime scene survey- This is also referred to as a “walk-through.” The following

guidelines should be noted.

i) The walk-through approach is to mentally prepare a reconstruction theory

that can be used, changed or utilized as the investigation process unfolds.

ii) It is important to note any transient or conditional evidence that requires

immediate protection or processing.

iii) Be mindful of any weather conditions that may interfere with the crime

scene.

At the crime scene-

Hand Writing Analysis

1. This examines the authenticity of signatures or handwriting.

2. Attempts to identify fraudulent documents

3. Questions typewritten documents

4. Tries to detect forged documents

Activity 2:14

Activity: Crime Investigation Tips

Develop a set of crime scene investigation Do’s

and Don’ts for your local police station.

Post your Do’s and don’ts in the forum and

react to those posted by your classmates.

Summary

In this session you had the opportunity to examine the techniques and characteristics of

crime scene investigation. The concept of managing the crime scene with particular focus

on using manpower, logistics, information and technology all play a crucial role in the

outcome of any criminal or civil investigation. Crime scene recognition, securing the

crime scene and surveying for successful high quality investigation is imperative.

References

http://www. Forensic.com

Wrightsman L. (2003) Forensic Psychology. Thomson Wadsworth.

http://www.education.forensics