Download presentation
Presentation is loading. Please wait.
Published byRandolph Rose Modified over 6 years ago
1
Chapter 8 Autopsy © 2012 Cengage Learning. All Rights Reserved
2
Introduction—Objectives
Discuss the history of coroners and medical examiners. Describe the steps of a death investigation. Discuss how laboratory tests are used to determine the contributing factors that led to someone’s death. Compare and contrast collection of biological and nonbiological evidence during an autopsy. Describe the organization and structure of the autopsy report. Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
3
Madison Rutherford In 1998, Rutherford drove his car off the road.
The car caught fire and Rutherford died. A $7 million life insurance policy would go to his wife, but only after an investigation. An autopsy revealed: the skull fragments were in an unlikely position the bones indicated arthritis the dentures records didn’t match Rutherford faked his death. Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
4
Introduction—Vocabulary
algor mortis - postmortem (after death) cooling of the body livor mortis- the pooling of the blood in tissues after death resulting in a reddish color to the skin rigor mortis- the stiffening of the skeletal muscles after death autopsy - a postmortem examination of the body, including dissection to determine cause of death cluster - a group of wounds
5
Introduction—Vocabulary
postmortem interval (PMI) – the interval of time between when death occurs and the body is discovered forensic pathologist- a medical doctor who is trained to identify why and how someone died and to present those findings in court.
6
Introduction When the cause of death is unclear or suspicious:
the government requires a death investigation performed by the medical examiner or the coroner One must sign the death certificate By law, deaths occurring under these circumstances must be investigated: Violent crime, suicide, or accident Within 24 hours of entering a hospital or having surgery A natural death when a doctor is not present or the patient is not under the care of a medical facility Occurs in police custody or in a correctional facility Results from a communicable disease that may pose a threat to public health.
7
Manner of Death Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
8
Historical Events (Obj 8.1)
Two systems of death investigation exist in the US The coroner system dates to 12th century England; sometimes the position: is an elected official requires a medical doctor requires a forensic pathologist. The medical examiner system dates back to 1870 1st medical examiner appointed in Massachusetts the first true medical examiner system was not developed until 1918 in New York an experienced physician with advanced training in pathology
9
A Death Investigation (Obj 8.2, 8.3, 8.4)
When there is a suspicious death, investigators conduct a death investigation. The purpose of the investigation is to determine the cause, mechanism, and manner of death. Three major phases of the death investigation: A preliminary investigation is conducted at the death scene. The body is transported to the morgue, where the medical examiner examines the body and performs an autopsy. The medical examiner orders lab tests on biological evidence collected during the autopsy.
10
At the Death Scene Draw sketches of the body at the scene
Take photographs of the scene position of the body the victim’s face for identification purposes the underside of the body and the surface beneath the body to make a visual record of lividity, blood, and trace evidence and any other characteristics that could provide clues to the medical examiner. Document signs of trauma Estimate time of death Postmortem Interval (PMI)
11
Postmortem Interval The time between the death and the discovery of the body Evaluate livor mortis and rigor mortis Look for scene markers Nonbiological evidence that provides clues about the time of death Example: unopened mail or newspaper near the body; dated sales receipts in victim’s pockets Collect evidence Establish a chain of custody Interview the victim’s family Check medical records and police reports
12
Estimating Time of Death
The degree of decomposition also helps death investigators estimate the time of death. Death investigators look for obvious signs of decomposition and for evidence called scene markers that provides clues about the time of death. Scene markers are especially helpful if the body is severely decomposed.
13
Livor and Rigor Mortis Livor mortis Rigor mortis
is first apparent 30 minutes to 2 hours after death. It becomes fixed between 8-12 hours after death. Rigor mortis Stiffening of the body due to lack of ATP in muscle cells Occurs 2-4 hours after death Usually subsides after 36 hours This helps investigators estimate time of death Lighter areas indicate that this person’s shoulders were touching a hard surface
14
Medical Examination Arrival at the morgue Cause of death
Update the chain of custody: when the body arrives, who transported the body, and who received the body Cause of death Mechanism of death Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
15
External Examination Investigate clothing and body Order X-rays
Biological evidence—material from living or once-living sources Nonbiological evidence—material from nonliving sources Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
16
Autopsy Temperature generally falls 1.5ºF every hour until the body reaches ambient temperature Determine body temperature At the crime scene—rectally At the crime lab—in the liver Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
17
Autopsy Time since death (in hours) =
Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
18
Autopsy Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
19
Collecting Evidence Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
20
Collecting Evidence Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
21
Collecting Evidence Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
22
Evidence Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
23
Laboratory Analysis Toxicology—the science related to the detection of drugs, alcohol, and poisons Histology—the study of tissues Neuropathology—the study of disease and trauma associated with the nervous system Serology—the study of blood, semen, and other body fluids (for legal matters) Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
24
Toxicology Alcohol—gas chromatography Barbiturates and narcotics
Presumptive screening—urine immunoassay Confirmatory test—gas chromatography-mass spectrometry Tranquilizers—gas chromatography Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
25
Histology Slice tissue into very thin sheets Stain the tissue samples
Eosin (acidic)—for basic structures; Cytoplasm appears pink Red blood cells appear bright red Hematoxylin—binds to structures (e.g., ribosomes and the nucleus) Together—detect cancers Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
26
Histology Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
27
Neuropathology More than half of all deaths encountered by medical examiners are associated with the nervous system Common examinations: Brain trauma Brain cancer Alzheimer’s Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
28
Serology A forensic serologist may investigate:
Infections caused by blood-borne pathogens Blood-typing DNA profiles Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
29
The Autopsy Report (Obj 8.5)
Heading External Examination Evidence of Injury Internal Examination Findings and Opinion Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
30
Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
31
Autopsy Report Forensic Science II: Autopsy, Chapter 8
© 2012 Cengage Learning. All Rights Reserved
32
Chapter Summary In the US, the coroner or the medical examiner leads the death investigation when the cause of death is unclear or suspicious. Manner of death is classified as: natural, accidental, suicide, homicide, or undetermined. Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
33
Chapter Summary The three steps of a death investigation include:
determination of the events that surrounded and led to the death, internal and external examination, and laboratory analysis. Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
34
Chapter Summary An autopsy is performed if the cause of death is not known in order to: document injuries, exclude other causes of death, and determine factors that contributed to death. Biological evidence is material from sources that are living or were once living. Nonbiological evidence is material from nonliving sources. Forensic Science II: Autopsy, Chapter 8 © 2012 Cengage Learning. All Rights Reserved
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.