1 What is Forensic Pathology Definition investigation of

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What is Forensic Pathology? § Definition: - investigation of sudden, unnatural, unexplained or violent deaths - notice: not all deaths warrant autopsy Ex. Old age, terminal illness - but violent, suspicious deaths in healthy individuals and some accidental deaths warrant the use of an autopsy (post-mortem examination of a body to determine cause of death) 2

Modern Goals of Autopsies § Determine the identity of the decedent § Determine the cause of death § Determine the manner of death § Determine the mechanism of death § Determine time of death 3

Cause and Manner of Death Cause of Death -the injury or disease that initiated death -Ex. cancer Manner of Death -explains how the cause arose; such as natural, accident, homicide, suicide (sometimes undetermined) -Ex. Struck by lightening (accident) 4

The Medical Examiner § Requires a Doctor of Medicine Degree § Responsibilities include autopsy, histology, and forensic photography § Perform around 250 autopsies a year § Review around 1, 400 filed medical examiner cases a year § Provide instruction in Forensic Pathology § Salary: $97, 000 - $170, 000 a year* *Source: The Forensic Casebook pg. 174 -175 5

Examination Protocol § Most ME’s visit the scene § Dental/medical history can be provided if identity of victim is known § Any use of resuscitation, injections, IV or thoracic lines, intubations, or barehanded handling by medical personnel is vital knowledge 6

Examination Protocol § § § Visual inspection Injury inspection Internal examination Presentation to other experts Reconciliation of all exhibits Presentation of findings 7

Three Types of Decomposition Rigor mortis: § medical condition that occurs after death and results in the shortening of muscle tissue and the stiffening of body parts in the position they are when death occurs § Immediately following death, muscles relax and then become rigid § Occurs in the first 24 hours and disappears within 36 hours 8

Three Types of Decomposition Livor mortis: § Medical condition that occurs after death and results in the settling of blood in areas of the body closest to the ground § Skin appears as a dark blue or purple in the areas where the blood has settled due to gravity § Begins immediately following death and lasts up to 12 hours after death 9

Three Types of Decomposition Algor mortis: § Postmortem changes that cause a body to lose heat until it reaches room temperature § Good for determining time of death § Average heat loss: 1 degree F per hour § Affected by clothing, weather conditions, fat content 10

Visual Inspection § Before the visual inspection begins, blood is drawn, X-rays taken, and inspected for sharps § Visual examination can begin with a nude or clothed body § Entire body is photographed 11

Visual Inspection cont… § Clothing is examined for rips, tears, or trace evidence § Clothing is removed, dried, & packaged; descriptions of clothing (including size/brand) recorded for autopsy report § Blood-stained clothing sent out for examination; blood stains on body swabbed for identification § Head combed for trace, foreign hairs, & other evidence 12

Visual Inspection cont… § Rape kit may be included at this stage if warranted § Body openings (ears, vagina, etc. ) examined foreign objects/trace evidence § Hands (bagged at the scene) are examined; fingernail scrapings § Fingerprint/footprint cards taken § Entomological samples taken if needed § Notations of visual injuries are made & photographed; tattoos/body markings noted § General health noted along with hair & eye color 13

Visual Inspection cont… § UV photography used to reveal old bruises or new ones not yet surfaced § Lasers/oblique lighting turn up trace such as hair, pollen, blood, saliva, semen, even fingerprints § Birthmarks, tattoos, & distinguishing scars used as recognizable marks for identification 14

Injury Inspection Penetrating wounds -caused by bullets, knives, bombs, etc. - full extent of these wounds requires more than visual examination Non-penetrating wounds - caused by blunt force trauma, hand/finger impressions, burns, needle marks 15

Injury Inspection cont… § Penetrating wounds such as those caused by bullets draw special attention - presence of gunpowder around wound - long range bullet wounds result in a hole with no other surface information - shots held to the skin give a hole & “rim burn” - short range shot may singe body hair and leave similar marks as a skin-held shot but no burn mark - inches to feet away shots leave “stippling” marks 16

Injury Inspection cont… § Bullet wound can change shape because skin is elastic so gun caliber cannot always be estimated § Gunshot entry wounds are usually smaller than exit wounds § Bullets that hit bone often leave a star pattern on bone surface § Knife wounds are three dimensional; recognizable by experienced examiners without casting; most are by kitchen ware 17

Injury Inspection cont… § Non-penetrating wounds - blunt-force trauma leaves marks - hand & finger impressions on skin are measured for finger span and size - bite marks can be photographed and cast made - burns; frost bite; rope marks from hangings appear with an upward angle (fake ones have a horiz. line) - needle marks indicate drug use 18

Internal Inspection (Autopsy) § Most dissections begin with a “Y” incision over the torso § One cut - arc across chest from shoulder to shoulder § Second cut - long cut that extends from base of the breast bone to the pubic bone (curves around navel) 19

Internal Inspection (Autopsy) cont… § Organs are removed from the top down; each is massed out on a scale § Rib cutters and spreaders open the chest § Lungs are examined for damage and heart tissue will be sampled 20

Internal Inspection (Autopsy) cont… § Throat, esophagus, trachea, and upper spine examined; broken hyoid bone indicates strangulation § Stomach contents are examined and help determine time of death; tie victim to a specific place & time; intestines examined as well § Liver, spleen, & pancreas are sectioned for histology & drug presence 21

Internal Inspection (Autopsy) cont… § Bladder sample taken (urine) for testing of drugs § Presence of blood in urine can mean blunt force trauma over the kidneys § Women are examined for pregnancy, sexual interference, & semen § Once the internal examination is complete, the organs are replaced inside the body & the body is sewn up 22

Internal Inspection (Autopsy) cont… § Head is examined last; eyes are first § Hemorrhages to the eyes or lids (petechiae) indicate lack of circulation to the head (strangulation) § Single incision made - arch from one ear, over forehead, to other ear; face is flipped forward § Face area is examined for bruising beneath the skin § Skull is opened with a saw; brain examined and weighed 23

Other Autopsy Facts § Exhumations - body that has been buried is dug up for examination § Partial bodies/Amputations - ME sometimes must “reconstruct” a victim from their body parts - body parts can sometimes help police reconstruct the crime or profile the killer 24

Presentation to Other Experts § Medical examiners are NOT expected to see EVERY trauma ever inflicted on a victim § ME must rely on histology, toxicology, and other fields to help with cause of death ex. Scuba deaths, animal bites, pharmacy 25

Reconciliation of All Exhibits § Prior to the completion of the autopsy, all samples, reports, and exhibits are accounted for and checked for accuracy § All evidence (ex. bullets) is returned 26

Presentation of Findings § Final presentation is the autopsy report § Describes all findings, steps taken, and opinion of the examiner on the cause, method, and manner of death 27

Forensic Odontology § Definition: the application of dental science to help identify individuals and the study of teeth in bite mark analysis § Job title: Forensic odontologist 28

Identifying Remains § Victims can be identified by using a complete jaw, fragment of a jaw, or even just a few teeth § Dental x-rays best source for identification § Show relative positions of teeth, fillings, and other materials contained in the tooth § Forensic odontologist may also assist in the autopsy (take notes on teeth and cranial features) § Police use these dental findings, enter them into a computer and look for a close comparison 29

Example of Dental filling 30

Identifying Unknown Remains cont. § Often called to mass disaster sites (such as airplane crashes, fires, bombings, terrorist attacks, etc. ) § May be called to mass graves after political crimes of massacres have been committed (ex. Rwanda and Guatemala) 31

Analyzing Bite marks § Criminals (and victims) sometimes leave bite marks § Can link a suspect to a victim and vice versa § Dental impressions often left in food too (chewing gum; also a good DNA sample) 32

Computer Imaging with Dental Records § Computer imaging technology can generate an outline of teeth § It is laid over top a digital photograph of the human bite mark on the victim § Called “compound overlay” 33

Computer Imaging continued § Image can be zoomed in for a close up § Look at edges of suspect’s teeth and compared with the injury pattern § In court, forensic odontologist would then testify to the strong association between the victim’s injury marks and the dental impressions of the suspect 34

How to Become a Forensic Odontologist? § First become a dentist § Need bachelor of science degree § Go to dental school (Doctor of Dental Science) § Gain experience in the field of dentistry § Take courses on forensic odontology supported by the American Board of Forensic Odontology 35