homicide chapter 14. copyright ©2008 the mcgraw-hill companies, inc. all rights reserved. 2...

Homicide

Chapter 14

Copyright ©2008 The McGraw-Hill Companies, Inc. All rights reserved.

2

HOMICIDE AND THE LAW• The types of deaths that confront the police can be

divided into four major categories: – Homicide– Natural causes– Suicide– Accidental causes

• The goal of classifying a death in one of these categories is to assign responsibility in both a moral sense and a legal sense.


3

HOMICIDE AND THE LAW

• Homicide – The intentional or negligent killing of one human

being by another.

• Justifiable homicide– The killing of another in self defense or defense of

others when danger of death or serious bodily harm exits.


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• Excusable homicide– The killing of a human being without intention and

where there is no gross negligence.

• Criminal homicide (felonious homicide) – The wrongful killing of a human being without

justification or excuse in the law. Typically, there are two degrees of the offense:

• Murder• Manslaughter


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• Murder – The unlawful killing of a human being by another

with malice aforethought.• Felony murder

– The killing of a person during the commission or attempted commission of a felony other than murder (e.g., during a robbery).

• Most state statutes provide for varying degrees of murder, such as first-degree and second-degree murder, or “murder one” and “murder two.”


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• Manslaughter – The unlawful killing of another without malice. – It may be:

• voluntary, upon sudden heat of passion• involuntary, in the commission of an unlawful act• negligent, occurring as a result of an action that could

have been avoided


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• Voluntary manslaughter is intentionally killing another in the sudden heat of passion caused by words or actions that provide a provocation.

• Involuntary manslaughter is accidentally killing another as a result of an act of extreme and culpable negligence.


8

Murder and Corpus Delicti

• Corpus delicti is the actual body in a murder case, but corpus delicti also can be used to mean any material evidence of a crime or objective proof in a criminal case.


9

Murder and Corpus Delicti

• One does not always need to produce the body to obtain a conviction of murder.

• It is possible to prove the corpus delicti of a murder case by presenting presumptive (circumstantial) evidence that suggests the defendant’s guilt beyond reasonable doubt.

• The murder trial of John Webster


10

Modes of Death

• Accidental Deaths– May include a backyard pool drowning, an

accidental fall down a flight of stairs, an unintended drug overdose, a hunting accident, and so forth.

• Natural Causes– Heart attacks, strokes, various diseases, and even

simply old age.


11

Modes of Death

• Suicides– Shooting, poisoning, hanging, drug overdose,

carbon monoxide, and wrist cutting are all commonly employed by individuals seeking to kill themselves.

• Criminal Homicides (Murders)– Murder involves an individual intentionally killing

another through any of an assortment of methods.


12

MOTIVES FOR HOMICIDE

• If an underlying motive for the homicide can be determined, a suspect may be identified.

• Motive gives the investigation a kind of focus and helps the investigator better understand why a homicide has occurred.


13

Unplanned or Spontaneous Murders• Use of drugs or alcohol, resulting in a fight that turns

lethal• Reaching for a handgun or rifle during the heat of an

argument• Dispute between a boyfriend and girlfriend• Dispute between friends over a boyfriend or girlfriend• Disagreement over money or a business transaction• Heat of passion when a spouse discovers his or her

partner is cheating with another• Unintentional killing during the commission of another

crime, such as robbery or burglary


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Unplanned or Spontaneous Murders

• Spontaneous murders lack planning and premeditation and are highly related to opportunity.

• Jealousy or emotionally charged disputes are typically at the root of spontaneous murders.

• Spontaneous murders have a high clearance rate because witnesses and evidence are frequently available to the investigator.


15

Murder for Financial Gain

• Often occur between individuals who have a professional or contractual relationship or are linked as beneficiaries of a will or insurance policy.

• Unlike spontaneous homicides, murders for financial gain are carefully planned and generally meticulously carried out.


16

Sexually Motivated Murders

• May be planned and intentional or may occur spontaneously as a secondary aspect of a rape or another sex crime.

• Another type of sexually motivated murder is killing a spouse to make way for another mate.

• This is more likely when a large estate is under the control of the murdered spouse or when a divorce might result in the loss of large amounts of money or property.


17

Murder for Revenge

• “Did the deceased have any enemies?”• Drug dealers


18

Elimination Murders

• Elimination murders are committed to remove some obstacle to a desired goal.

• Checking on the background of the victim may provide clues to the reason for the murder.

• In some cases, the victim may have been eliminated because he or she was an informant or potential informant for police authorities.


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Motiveless Murders

• There are at least two forms of what might be called motiveless murders. These include:– stranger-to-stranger murders– mistaken identity murders

• Hate crimes• Mistaken identity murders are not especially

common


20

THE HOMICIDE INVESTIGATION• The responding officer’s first priority is to give

emergency aid to the victim, if he or she is still alive, or to determine that a death has occurred.

• There are a number of ways to determine whether a person is dead:– Appearance

• In death, the face becomes pale or ashen and waxy, the lower jaw drops a bit, and the mouth may sag open.

• The eyes become soft to the touch, and the eyelids may be open slightly but will show no sign of movement or reflex action when touched.


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Determining whether a Person is Dead

• Pupillary reaction: The pupils of a living person’s eyes contract when a bright light, such as a flashlight beam, is shined into the eyes.

• Pulse: A check for a pulse may be made on the wrist, inside the upper arm at the elbow, or under the chin at the neck.

• Visible breathing: Note the movement of the chest or abdominal area; a mirror placed just below the nostrils may also detect breath (as a fogging of the mirror).


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Determining whether a Person is Dead

• Nose– Listen or place hand at nostrils to hear or feel breathing.

• Muscle resistance or muscle reflex– Muscle resistance and reflex are present in the body to some

degree until death.– Note whether limbs can be moved without resistance.

• Cyanosis– In death, the lips become cyanotic, or bluish, as do the nail

beds.


23

Procedures in the Preliminary Investigation

• Record the time they were notified of the death complaint.

• Record the identification information about the complainant. Include the date and the location from which the complainant called.

• En route to the scene (depending on the elapsed time between the call and the alleged death) be alert for possible fleeing suspects, people with fresh wounds, torn or bloody clothing, or any sort of furtive or evasive actions.

• Record the time of arrival at the scene and the exact location.


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Procedures in the Preliminary Investigation

• Determine whether the victim is dead or severely injured. Request medical assistance if necessary.

• Use caution when approaching the victim to avoid disrupting or destroying possible evidence and to protect your safety in case the victim is armed.

• Determine and verify the identities of those present at the scene and anyone who left before the officers’ arrival.

• See full list on page 297


25

Arrival of Investigators and Medical Examiner

• The lead investigator will coordinate and direct all investigative assignments.

• As in any other criminal investigation, the homicide scene must be secured and protected, photographed and sketched, and all evidence must be carefully gathered, identified, preserved, and forwarded to the lab.

• In addition to securing and preserving physical evidence, investigators should identify and interview possible witnesses and suspects, as well as relatives and friends of the deceased.


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Arrival of Investigators and Medical Examiner

• All violent or suspicious deaths require the coroner or medical examiner to determine the time and precise cause of death.

• The determination of criminal responsibility in a death has evolved into a highly specialized field of medical science called forensic pathology.

• Forensic pathology– A specialized field of medicine that studies and

interprets changes in body tissue and fluids in relation to criminal investigation.


27

Identifying the Victim• Fingerprints

– Fingerprint identification is the most efficient way to identify the body of a murder victim.

– However, this technique is effective only if the victim’s prints are on file and if prints can be obtained from the corpse.

• Skeletal Studies– May provide a basis for identification. – This is especially true if the body has any skeletal peculiarities,

such as old fractures, metal plates or pins, or evidence of certain bone diseases.

– Also, bones may provide clues about the victim’s age, gender, and ethnicity.


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Identifying the Victim

• Visual Inspection– The victim may be recognized by someone who

knows him or her.– Visual identification combined with another

method, such as fingerprint matching, is a favored method for reliable identification.

• Personal Effects– Drivers license, jewelry, identification cards, or

letters in pockets, a wallet, or a purse.


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• Tattoos and Scars– Alone, these markings provide only tentative or

somewhat unreliable identification, but in conjunction with other, more reliable forms of identification, skin markings can lead to a positive identification.

• Odontology (Dental Evidence)– Teeth, fillings, inlays, bridges, crowns, and so forth is

valuable because teeth are among the most durable parts of the human body.


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• Clothing– Cleaner’s marks, labels, initials, and similar

information.– Articles of clothing in themselves are seldom unique

enough to provide a reliable basis for identification.

• Photographs– Photos of the victim are sometimes published in

local papers or shown on local news programs.


31

Estimating the Time of Death

• It is important to establish the time of death as precisely as possible.

• Typically, both the investigator and the medical examiner are responsible for estimating the time of death.

• Only when a murder has witnesses can investigators pinpoint the time of death with absolute precision.


32

Rigor Mortis• Rigor mortis

– A contracting of muscles of a body after death that disappears over time.

– Warm temperatures accelerate its appearance and disappearance, and cold slows it down.

– Usually begins two to four hours after death and affects the entire body in approximately six to twelve hours.

– Will frequently disappear in twenty-four to thirty-six hours.

– It disappears in about the same sequence as it appears. – The early stages of rigor mortis can be noted in the jaw.


33

Rigor Mortis

• Cadaveric spasm– A rigidity of certain muscles that usually occurs

when the victim is holding something at the time of death and the hand closes tightly around the object.

– Sometimes a sign of suicide.


34

Livor Mortis (Postmortem Lividity)

• Livor mortis– A dark discoloration of the body where blood has

pooled or drained to the lowest level– Also called postmortem lividity.– It is caused by blood draining to the parts of the

body nearest the ground when the heart stops beating and circulating the blood.

– It is especially useful to consider when determining if a body may have been moved after death.


35

Livor Mortis (Postmortem Lividity)

• Lividity usually begins within one hour after death, congeals after three or four hours, and reaches a maximum in ten to twelve hours.


36

Body Temperature

• After death, the body tends to lose heat at about 1 to 1.5 degrees per hour until it reaches room temperature.

• Factors influencing the time required to cool the body include the difference in temperature between the body and the medium in which it is found.


37

Body Decomposition

• Decomposition is the breaking down of a human body due to the effects of temperature, animal and insect attack, and general putrefaction through the softening and liquefaction of tissue and the conversion of soft tissues to liquids and gases.

• The actual rate at which the human body decomposes depends on a number of factors: – air temperature– levels of moisture– the body’s own bacteria and enzyme levels– assaults by animals or insects


38

Body Decomposition• The human body has a greater specific gravity

than water, and a corpse may sink initially when placed in water.

• However, within three days to a week (depending on water temperature) the body will surface because of the formation of gases.

• Adipocere – A whitish-gray, soapy or waxy substance that forms

on the surface of a body left for weeks in a damp location.


39

Carrion Insects

• Forensic entomologist – A person who specializes in the study of insects in

relation to determining the location, time, and cause of death of a human victim.


40

Estimating the Time of Death

Other Indicators• Contents of the stomach• Watches and other timepieces


41

Developing a Suspect

• Suggested investigative procedures for developing a case against a suspect who is in custody:– Administer a polygraph examination if the suspect is

willing and signs a waiver of legal rights.– Have the suspect reenact the crime, and make a

videotape of this reenactment.– Take photographs of the suspect.


42

Developing a Suspect

• Collect fingernail clippings and hair samples from the suspect.

• Examine the suspect for wounds, bite marks, or scratches.

• Take fingerprints of the suspect, and check them against available files.

• Check all telephone calls made by the suspect during the recent past, and verify the identities of people called.

• Verify all statements made by the suspect to either corroborate or disprove information given by witnesses or other sources.


43

TYPES OF DEATHS INVESTIGATEDAND WEAPONS USED

Natural Death• In natural deaths, the coroner or the medical

examiner’s office is primarily interested in establishing a cause to: Rule out unnatural causes Determine whether the death was an accident, a

suicide, or a homicide Eliminate dangerous conditions Determine liability


44

TYPES OF DEATHS INVESTIGATEDAND WEAPONS USED

Suicide• Many deaths by suicide have all the outward

appearances of murder to an untrained eye.• As a rule, however, self-inflicted injuries have

certain fairly predictable physical features.• Notes:

– If a note is found, investigators should be careful not to handle it and should learn whether other members of the family or witnesses have already handled it.


45

Procedures in Suicide Investigations

• Examine the victim. If doubt exists about the victim’s being dead, call for an ambulance and administer first aid while awaiting the ambulance.

• If the victim is obviously dead, observe the scene carefully for indications of a struggle, the locations of objects in the room, the positions of chairs, the contents of ashtrays, and any weapons, pills, prescription bottles, glasses, suicide notes, and so on.

• Notify headquarters of findings at the scene and request the coroner.

• Be alert for efforts to make the victim’s death appear accidental.


46


• Ask about the medical history, ailments, medications taken, and prescriptions (type, when filled, amount remaining, etc.).

• Examine any containers of prescription drugs and the accompanying labels. – A prescription drug label should have the name of the drug and the

name of the physician who issued the prescription. – Generally, the name of the pharmacy is also on the label. – The label should also indicate the date the prescription was filled,

the number of tablets or capsules originally in the container, and the recommended dosage.


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• Note the location of the medication and any indication of overdose or recent use. – Also note any containers (glasses or cups) or loose tablets or

capsules near the body.• Check with relatives, friends, and neighbors.

– Before committing suicide, a person may make suicidal statements, give away personal items, or engage in certain other behaviors.

• Check for suicide notes (usually found quite close to the body). – With handwritten notes, compare the handwriting on the

note with known samples of the victim’s writing. • Preserve the note.


48

Poisoning• Poisoning is among the oldest methods of

murder.• Many poisoning attempts are thwarted because

the assailant uses too much poison. – As a result, the victim vomits up most of the toxin

before it can cause lethal damage.

• Toxicological screening– An examination of body tissue or fluids for poisons

or other toxins.


49

Stabbing and Cutting Wounds• Stabbing and cutting wounds differ in depth,

shape, and size.• Incisions are made quickly by the sharp edge of

an instrument, so bruises are usually not present.• As a general rule, incisions are deepest at the

point where the cutting edge of the instrument first cut the skin.

• Thus, the direction of the wound can be determined by examining the cut from its deepest to shallowest points.


50

Stabbing and Cutting Wounds

Cutting wounds produced by a single-edge blade

Penetrating stab wound caused by a sharp object

Lacerations on head from tire iron

Defense stab wound on inside of arm


51

Stabbing and Cutting Wounds

Defense wounds– Injuries on the hand or forearms of a victim who has

attempted to fend off an attack.– Investigators should carefully examine the hands,

arms, and shoulders of victims to identify possible defense wounds.

– Bruises on the knuckles of a victim should also be noted because they may indicate that the victim struck his or her assailant.


52

Gunshot Wounds

• Investigators should note both the entry and exit wounds of a gunshot.– Wipe ring (smudging)

• A gray ring around a gunshot wound resulting from the deposit of gunpowder by a gun blast at close range.

– Tattooing • The burned skin around a gunshot wound resulting from

a gun blast (muzzle flash) when fired at close range.


53

Gunshot Wounds


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Gunshot Wounds• When a gun is fired while being held against the skin of

the victim, a contact wound results.– Contact wound

• A wound created when a gun is fired while being held against the skin of the victim.

• Typically found in self-inflicted wounds and in some execution-type murders.

– The difference between entry and exit wounds is observable. Exit wounds are:

• generally larger than entry wounds• are likely to bleed more profusely than entry wounds• are often irregularly shaped


55

Asphyxia

• Asphyxiation– Death due to a lack of oxygen and an excess of carbon

dioxide in the blood.– Body discoloration

• Usually quite pronounced and is characteristically blue.– In cases of asphyxiation from strangulation, one frequently

finds hemorrhaging in the eyes (broken blood vessels in the white portion, which appear as red blotches, known as petechiae.


56

Asphyxia• Strangulation

– External pressure closes the airway or compresses the main arteries in the neck

– Oxygen is withheld from the lungs– Blood supply to the brain is drastically curtailed– Death occurs

• Hanging– Most hangings are suicides, but some are accidental. – Victims are found in sitting, standing, and lying positions.– Belts, towels, bandages, wire, fabric strips, rope, and

assorted other tying materials are used.


57

Characteristic Bruise Patterns in Homicide and Suicide Strangulation


58

Asphyxia

• Hanging– Hanging does not require that the body drop or

swing freely, because only pressure is required to cause death.

– In hangings, ligature marks typically start below the chin and travel up diagonally toward the ears or the top of the head.


59

Asphyxia

• Smothering– A fairly uncommon mode of murder.– People under the influence of drugs and alcohol, invalids, the

aged, and infants are much more likely to be victims of accidental smotherings.

– In each of these cases, the victim is likely to turn face down onto a pillow or to become tangled in blankets and, owing to an intoxicated or weakened condition, accidentally smother to death.

• Infanticide


60

Asphyxia

• Choking– Choking involves a foreign substance or object

blocking the throat and airway and generally is accidental.


61

Asphyxia

• Carbon Monoxide Poisoning– Death from carbon monoxide may be an accident, a

suicide, or occasionally a homicide.– Perhaps the most frequent source of carbon

monoxide poisoning is the exhaust of a car.

• Volatile Intoxicant Sniffing– Volatile intoxicants include all substances that when

inhaled produce altered states of consciousness.– “Huffing”


62

Asphyxia• Drug Overdoses

– The respiratory center of the central nervous system is depressed by certain drugs.

– Muscle paralysis, including paralysis of the muscles of respiration.

• Autoerotic Asphyxiation– Seeking sexual gratification by near asphyxia.– A rope or other ligature around the neck reduces

the flow of air and oxygen to the brain, and at the same time, the individual may masturbate.


63

AsphyxiaAutoerotic Asphyxiation • Typically, the body of the victim is found nude or with

genitalia exposed. • In some cases, men are found dressed in women’s underwear

or clothing. • There is often evidence of masturbation.• There may be sexually stimulating paraphernalia, such as

vibrators, sexual aids, or pornographic photos or magazines. • Protective measures may have been taken, such as placing

padding between the ligature and the neck to prevent marking.

• Mirrors, intended to allow the victim to observe the ritual, may be found near the body.


64

Asphyxia

Drowning• Death by drowning results when any liquid

enters the breathing passages and prevents the access of air to the lungs.

• A person can drown when only the mouth and nose are under the surface.

• Most drownings are accidents.


65

Vehicular Manslaughter

• Vehicular manslaughter may involve:– one or more cars– a collision with a pedestrian, or the death of one or

more passengers – may result from gross negligent behavior– reckless driving– driving while under the influence of alcohol or other

mind-altering substances


66

Vehicular Manslaughter

• See investigative procedures on page 296.


67

Suspicious Circumstances

• The criminal codes of many states provide for various circumstances in which a physician, funeral director, or other person shall notify the coroner’s office of a death that may have occurred under suspicious circumstances.

• May order the Autopsy.

homicide chapter 14. copyright ©2008 the mcgraw-hill companies, inc. all rights reserved. 2...

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