chapter 5 death investigation customized

CriminalisticsCriminalisticsAn Introduction to Forensic ScienceAn Introduction to Forensic Science

CHAPTER

Criminalistics: An Introduction to Forensic Science, 11eRichard Saferstein

Copyright © 2015 by Pearson Education, Inc.All Rights Reserved

ELEVENTH EDITION

Death Investigation

5



Role of Forensic PathologistRole of Forensic Pathologist• Also known as a medical examiner are responsible

for determining the cause of an undetermined or unexpected death.

• They work with law enforcement during a death investigation.



Coroner vs. Medical ExaminerCoroner vs. Medical ExaminerCoroner – an elected official that may or may not possess a medical degree. •Established hundreds of years ago during the ruling of King Richard I of England – used to collect money and personal possessions of people who had died.



Coroner vs. Medical ExaminerCoroner vs. Medical ExaminerMedical Examiner – almost always an appointed official and is usually a physician who is a board certified forensic pathologist. Responsible for certifying the manner and cause of death and recording it on a death certificate.

*Only a pathologist is trained to perform an autopsy.



Cause of DeathCause of DeathDetermination of Cause of Death Involves……•Autopsy•History of death•Witness statements•Relevant medical records•Any scene investigation

Forensic pathologist cannot personally attend every death scene, therefore scene investigation delegated to trained investigators (ie. Deputy Coroners).



Scene Investigation Scene Investigation The Death Investigation Involves:•Documenting and photographing the undisturbed scene.•Collecting relevant physical evidence.•Attempting to determine the cause of death.•Determining postmortem locations of the body.•Was there any postmortem movement of the body?•Examination of the body.



Scene Investigation Scene Investigation • A critical phase of the death investigation will be a

preliminary reconstruction of events that preceded the onset of death, so all significant details of the scene must be recorded..... Blood spatter and blood flow patterns must be

documented.

Any tire marks or shoe prints must be documented.

Fingerprints must be processed and collected.

Evidence discarded, dropped, or cast off by a perpetrator must be collected.



Scene Investigation Scene Investigation Weapons, fired bullets, and casings are collected and

documented.

Photographs must always be taken before the scene is altered in any way. This plays a large role in reconstruction of events later. Photo injures AND areas w/NO injuries.

Paper bags around the hands and secured at the wrist can preserve trace evidence.

Remove clothing/jewelry/personal effects from body.



Identifying the DecedentIdentifying the DecedentVisual examination and identification is easy if…..•The decedent has identification with him/her.•A family member can identify the person.

Difficult if……•There is extensive decomposition or trauma….



Identifying the DecedentIdentifying the DecedentIn difficult situations you can apply more sophisticated technology such as:

•DNA •Fingerprinting•Dental Examination and Records•Facial Reconstruction



CASE STUDYCASE STUDYOn Jan. 21, 2007, two homeless men in Chicago found a decomposed body in an alleyway wrapped in a shower curtain and stuffed inside this Casio Keyboard box.

The face was unrecognizable but the clothes and hairstyle was still intact.



CASE STUDYCASE STUDY• She went unidentified for a year before the cleaned skull

was submitted to a forensic artist/facial identification specialist.

• She developed 2D reconstruction drawings based on info from the pathologist and anthropologist.



CASE STUDYCASE STUDY• She then developed front and side view 3D reconstruction

sculptures.

• They were aired on America’s MostWanted TV show and website.



CASE STUDYCASE STUDY• An employee at a dental office saw the reconstructions and

contacted authorities which ultimately led to her identification.

17 year old Marlaina “Niki” Reed, ward of the state and a runaway.



CASE STUDYCASE STUDYWilliam MacIntosh, 51, was charged in 2010 for the murder. •Detectives submitted a piece of denim cloth used to bind the legs of the victim.•It came back positive for McIntosh’s DNA.•He plead guilty to the murder and was sentenced in 2015 to 33 years in prison.



The AutopsyThe Autopsy



The AutopsyThe Autopsy• An autopsy in its broadest definition is simply the

examination of a body after death (i.e., a postmortem examination).

• Clinical/hospital autopsy focuses on the internal organs findings and medical conditions.

• The goal of a forensic/medicolegal autopsy is to

determine the cause of death and confirm the manner of death, often to be used in criminal proceedings.



Documentation and PhotographyDocumentation and PhotographyDocumentation – should include date, time, place, by whom the autopsy was performed, and who attended.

Photographs – photo injuries, with scale, and each photographs location (log).•Negative photographs depicting areas with NO injury are also important.•Correlate external wounds with internal damage.



Evidence from the AutopsyEvidence from the Autopsy• The medical examiner or coroner will carefully

examine the victim (internal and external) and develop meaningful correlations between the sustained injuries and the crime scene.

• Tissues and organs will be retained for pathological and toxicological examination.

• At the same time, arrangements must be made between the examiner and investigator to secure a variety of items that may be obtainable from the body for laboratory examination…..



Evidence from the AutopsyEvidence from the Autopsy• The following are to be collected and sent to the

forensic laboratory:1. Victim’s clothing2. Fingernail scrapings/clippings3. Combings from head and pubic hairs4. Buccal swab (for DNA typing purposes)5. Vaginal, anal, and oral swabs (in sex-related crimes)6. Recovered bullets from the body7. Hand swabs from shooting victims (for gunshot residue

analysis)8. Swabs of body areas suspected of being in contact

with DNA arising from touching or saliva



External ExaminationExternal Examination• The forensic autopsy consists of an external examination

and an internal examination.

• The first steps taken for the external examination include a broad overview of the condition of the body and the clothing.

• Damage to the clothing should be matched up to the injuries.

• Note presence of tattoos, scars, track marks, medical intervention.

• Paper bags are put on hands to preserve trace evidence.



External ExaminationExternal Examination• The external examination also consists of classifying the

injuries. This includes distinguishing between different types of wounds:1. Stab wounds (sharp-injury wounds)2. Gunshot wounds3. Abrasions4. Contusions (bruises)5. Lacerations (BFT)



External ExaminationExternal Examination• Look for other injuries to the body that can give you

information….for example1. Petechiae – hemorrhages in the eyelids - strangulation2. Damage to genital area – signs of sexual abuse3. Stippling or tattooing around a bullet hole - distance

X-rays are used to locate bullets, bullet fragments, knife fragments, shot pellets, etc. Can also identify bone fractures.



External ExaminationExternal Examination

Stellate Tearing



Bullet recovered from skullBullet recovered from skull



Close-up of BulletClose-up of Bullet



Stippling/TattooingStippling/Tattooing

Skin must be primary contact – will not see this if the bullet went through clothing first.



Internal ExaminationInternal Examination• The dissection of the human body generally entails the

removal of all internal organs through a Y-shaped incision beginning at the top of each shoulder and extending down to the pubic bone.

• Performing the internal examination entails weighing, dissecting, and sectioning each organ of the body.

• Portions of the internal organs are retained for microscopic examination.



Evaluation of Internal OrgansEvaluation of Internal Organs



ToxicologyToxicology• The internal examination is also where toxicological

specimens are taken. These include samples of blood, stomach content, bile, urine, brain, liver, and vitreous humor.

• Blood is often routinely tested to determine the presence and levels of alcohol and drugs. Never collect blood from the body cavity, may be contaminated.



Stomach ContentsStomach Contents



ToxicologyToxicology• Substance abuse is so common, that a forensic pathologist

will routinely order toxicological tests for the presence of drugs in nearly all autopsies.

• Postmortem Redistribution - Some drugs redistribute or reenter the blood after death and thus may complicate the interpretation of postmortem blood levels of these drugs.

• Toxicology results can help determine if the levels present in the body are therapeutic, toxic or fatal.



Cause of DeathCause of Death• A primary objective of the autopsy is to determine the

cause of death.

Definition: Identifies the injury or disease that led to the chain of events resulting in death.

In the case of prolonged death:• The decedent may have actually suffered from adverse

medical conditions brought on by the initial injury then die as a result of those conditions.

• Pathologists job is to determine if the underlying cause of death was the initial injury inflicted.



Cause of DeathCause of DeathCommon causes of death:1.Blunt force injury2.Sharp force injury3.Asphyxia4.Gunshot wound5.Substance abuse



Cause of DeathCause of Death• Blunt force injuries:

Are caused by a non-sharpened object such a bat or pipe.

Can cause lacerations (skin splitting and tearing). Can crush tissue and cause bleeding from tiny ruptured

blood vessels within and beneath the skin, known as a contusion (bruise).

Exhibit abrasions around the open wound, tissue bridging within the open wound, and torn or disturbed tissue beneath the skin surrounding the open portion of the wound.

Bruises can sometimes exhibit the pattern of the weapon used.



Cause of DeathCause of Death• Blunt force injuries:



Cause of DeathCause of Death• Sharp force injuries occur from weapons with sharp

edges, such as knives, blades or glass.1. Cut – is longer than it is deep2. Stab – is deeper than its length

• Tissue is not torn or crushed but sliced.• The scene is usually very bloody.

Note: presence or absence of defensive wounds on the victim.Usually occurs on the forearms and hands as the victims fights

off the attacker.

What do the lack of defense wounds tell you??? Victim tied up or unconscious during the assault.



Defensive WoundsDefensive Wounds



BFT vs. Sharp Force InjuryBFT vs. Sharp Force Injury



Cause of DeathCause of Death• Asphyxia encompasses a variety of conditions that

involve interference with the intake of oxygen. For example, death at a fire scene is caused primarily by the extremely toxic gas, carbon monoxide.

• A physical sign of carbon monoxide poisoning is the cherry-red discoloration of the body.

• Levels of carbon monoxide in the body can determine if an individual was breathing at the time of the fire since it does not continue to build after death. Soot in the airway is another indication.



Carbon Monoxide PoisoningCarbon Monoxide Poisoning

Carboxyhemoglobin



Carbon Monoxide PoisoningCarbon Monoxide Poisoning



Cause of DeathCause of DeathHanging vs. Strangulation

•Hanging is another example of death by asphyxia. Blood flow stops to the brain.

Petechiae (capillaries burst in eyes) is present as an indication (also in strangulations).

Hyoid bone and thyroid cartilage are not fractured in hangings, common in strangulation.

Remember to document how the victim was found and position of noose.

Preserve noose – slip off or cut away from knot. Defense wounds common for strangulations. Smothering can be homicide or accidental.



FIGURE 5–6 Petechial hemorrhages in a victim’s eye.Courtesy Elizabeth A. Laposata, MD, FCAP, FASCP, Forensic Pathology & Legal Medicine, Inc., Providence, RI

A result of capillaries bursting in the tissue

Also present in strangulation and smothering cases



Cause of DeathCause of Death• Gunshot wounds originate from projectiles fired by a

firearm. The distance a weapon was fired from a target is one of the most important factors in characterizing a gunshot wound.

• How you can determine the distance a weapon was fired?:1. Appearance of the wound2. Powder distribution around the wound3. Use powder distribution from test fires if you have a weapon



Cause of DeathCause of Death• Wound track determination

The path the projectile takes through the body Observe the wound externally Follow the track through the body Document its terminus All projectiles are recovered from the body for forensic

analysis



Role of the Pathologist Role of the Pathologist What A Bullet Does To A BodyWhat A Bullet Does To A Body



Bullet Going Through GelatinBullet Going Through Gelatin



Bullet hole in skullBullet hole in skullIs this a photo of the interior or exterior of the skull?



Stippling Around Bullet WoundStippling Around Bullet WoundCan be used to determine distance shooter was from victim



Stellate TearingStellate Tearing

Close contact Close contact bullet holebullet hole



Shotgun WoundShotgun Wound



Cause of DeathCause of Death• Substance Abuse - Death as a result of substance abuse,

illicit or prescription is an enormous problem in the United States.

• Drug abuse can directly cause death, or it can cause complications that can serve as a contributing factor to death.

• Death as a result of years of abuse is ruled as a natural.

• Drugs can alter a person’s judgement and psychomotor skills and often lead to act’s of violence.



Manner of DeathManner of Death• The manner of death relates to the circumstances that led

to the fatal result and is the culmination of the complete investigation.

• The manner in which death occurred is classified in death certificates as one of five categories: 1. Homicide (intentional death at the hands of another)2. Suicide (intentional lethal act by one person)3. Accidental (ie. traffic accidents, OD’s, drownings)4. Natural (ie. disease & continual environmental abuse)5. Undetermined



Manner of DeathManner of Death• Homicide:

Definition – a nonaccidental death resulting from grossly negligent, reckless, or intentional actions of another person.

• Suicide: Must be demonstrated that they acted alone. Common methods include: hanging, self-inflicted GSW’s, and

drug overdose (intentional act). Check personal history (inc.l psychiatric), threats/past

attempts, suicide note, location of wounds. Common areas for GSW’s – mouth, forehead, temple and

chest. Weapon should be present and bloodstain patterns should be

consistent with event.



Manner of DeathManner of Death• Accidental:

Definition – no intention to cause harm through gross negligence on the part of the perpetrator or the victim.

Types - Traffic accidents, drug overdoses, and drownings. The presence of drugs and/or alcohol in the victim’s system

can potentially affect the determination.

• Natural Causes: Death through disease and continual environmental abuse. Include: chronic drug and alcohol abuse, longtime exposure

to natural toxins or asbestos.



Manner of DeathManner of Death• Undetermined

When a rational classification cannot be established. Mechanism of death cannot be determined by a physical

finding at autopsy or because of the absence of meaningful findings in the toxicological and microscopic examinations.



Estimating Time of DeathEstimating Time of Death• A pathologist can never give an exact time of death.

However, there are many characteristics that the examiner can analyze in order to arrive at an approximate time of death. Algor mortis

• Definition: a process that occurs after death when the body temp cools until it reaches room temperature.

Results in the loss of heat by a body as general rule the body loses heat by 1 to 1 1/2 degrees Fahrenheit per hour until the body reaches the environmental temperature.

Factors that influence this – ambient temp, body size, and victim’s clothing.



Estimating Time of DeathEstimating Time of Death Livor mortis

• Definition: A medical condition that occurs after death and results in the settling of blood in areas of the body closest to the ground.

Results in the settling of blood in areas of the body closest to the ground (begins 20 minutes to three hours on death and continues up to 16 hrs).

At that point the lividity is fixed and tested on scene by applying pressure to blanch the lividity (press it out of the vessels when the skin is pressed).

Different lividity patterns could indicate that the body was moved after death and before it is fixed.



FIGURE 5–10 Livor mortis.Courtesy Elizabeth A. Laposata, MD, FCAP, FASCP, Forensic Pathology & Legal Medicine, Inc., Providence, RI

Lividity patterns in a body may indicate if the body was moved after death



Estimating Time of DeathEstimating Time of Death• Rigor mortis

Definition: A medical condition that occurs after death and results in the shortening of muscle tissue and the stiffening of body parts in the position at death (occurs within the first 24 hrs. and disappears within 36 hrs.).

Subsides and gone after about 36 hours under avg conditions. Hot environment can speed this up.

It will develop in the position that the body was in at the time of death.

Infants, elderly or obese people may not develop rigor b/c oc decrease muscle mass.



FIGURE 5–11 Rigor mortis in the arm of a decedent.Courtesy Elizabeth A. Laposata, MD, FCAP, FASCP, Forensic Pathology & Legal Medicine, Inc., Providence, RI



Estimating Time of DeathEstimating Time of Death• Potassium Eye Levels:

Forensic pathologists can determine the amount of potassium in the vitreous humor and use it to approximate the time of death.

• Stomach Contents: Stomach contents may reveal the deceased’s last meal. The

extent of digestion can help with determining the time of death or location.

Can contain partially digested or dissolved pills.



Estimating Time of DeathEstimating Time of Death• Decomposition: once this has set in, all other method

are useless.

Two Decomposition Processes:1. Autolysis – self digestion by the cells’ own enzymes.2. Putrefaction – decomposition by microorganisms such as

bacteria. Physical changes – bloating, discoloration, skin slippage and smell caused by accumulating gases.



Estimating Time of DeathEstimating Time of Death• The rate of both processes are dependent on the

mechanism of death.

Sequence of changes:1. Green discoloration begins in the abdomen.2. Darker green or purple discoloration follows on the face.3. Skin blisters with gas then peels. (slippage).4. Bloating (bulging eyes and

protruding tongue.5. Chest/extremities discolor and

bloat.



Estimating Time of DeathEstimating Time of Death• Decomposition:

Adipocere – a waxy substance that may for during the postmortem period of decomposition.

Typically takes 3 months to develop and adds a white or gray waxlike consistency to fatty tissues in the face and extremities that can take on a yellow to tan color.



Forensic AnthropologyForensic Anthropology• Forensic anthropology is concerned primarily with the

identification and examination of human skeletal remains.

• Skeletal bones are durable and undergo an extremely slow breakdown process that lasts decades or centuries.

• They can provide a multitude of individual characteristics long after a victim’s death including:1. Victim’s Sex2. Approximate Age3. Race4. Height5. Nature of a physical injury



Forensic AnthropologyForensic Anthropology• The gender of a decedent can be determined by the

size and shape of various skeletal features, especially those in the pelvis and skull.

• Female pelvic bones tend to show a wider, more circular than that of a male pelvis because of a woman’s child-bearing capabilities.

• The possible racial ancestry of a decedent can be assessed by the appearance of various cranial features on the skeletal remains.



FIGURE 5–13a Frontal shot of female pelvis and hips. This view shows the wide, circular nature of the pelvic opening and the short, wide nature of the sacrum.Geoff Brightling/Dorling Kindersley Media Library



FIGURE 5–13b Human male pelvis. This view shows the narrow pelvic opening and long, narrow sacrum.Geoff Brightling/Dorling Kindersley Media Library



FIGURE 5–14 Male (left) and female (right) human skulls showing male skull’s larger size and more pronounced brow bone.Corbis



Forensic AnthropologyForensic Anthropology• The height of a victim when alive can be estimated

by measuring the long bones of the skeleton.

• A forensic anthropologist may also help create facial reconstructions to identify skeletal remains.



Forensic AnthropologyForensic Anthropology• The sites where human remains are found must be

treated as a crime scene.

• These scenes must be secured and thoroughly searched to locate all bones if they are scattered or other aspects of evidence such as footwear impressions or discarded items.

• All aspects of evidence must be documented and collected.



Forensic EntomologyForensic Entomology• Forensic entomology is the study of insects and

their relation to a criminal investigation, commonly used to estimate the time of death.

• Forensic entomologists can approximate how long a body a body has been left exposed by examining the stage of development of the fly larvae.



Forensic EntomologyForensic Entomology• By determining the oldest stage of fly found on a

body, entomologists can approximate the postmortem interval (PMI). The sequence of arrival of different insect species can

be used to estimate PMI.

The most common and important is the blowfly recognized by its green or blue color.

Blowfly eggs are laid in human remains and ultimately hatch into maggots, or fly larvae, which consume human tissues and organs.



FIGURE 5–21 Typical blowfly life cycle from egg deposition to adult fly emergence. This cycle is representative of any one of nearly ninety species of blowflies in North America.After E.P. Catts, Entomology and Death: A Procedural Guide. 1990, 2008



Forensic EntomologyForensic Entomology• These determinations are not always straightforward,

however. The time required for stage development is affected by environmental influences such as geographical location, climate, weather conditions, and the presence of drugs.

• If resources allow, all entomological, or insect, evidence should be collected by a forensic entomology expert who will take temperature readings and collect specimens from every area in which they are found.



Forensic EntomologyForensic Entomology

Collection Kits