Forensics Word

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[FORENSIC PATHOLOGY ] FORENSIC PATHOLOGY • FORENSIC SCIENCE – FORENSIC SEROLOGY – FORENSIC CHEMISTRY – FORENSIC GENETICS – FORENSIC BIOCHEMISTRY/MOLECULAR BIOLOGY – FORENSIC ANTHROPOLOGY – FORENSIC ODONTOLOGY – FORENSIC ENTOMOLOGY – FORENSIC BOTANY FORENSIC PATHOLOGY• FORENSIC MEDICINE – FORENSIC PATHOLOGY – FORENSIC OBSTETRICS – FORENSIC GYNECOLOGY – FORENSIC PEDIATRICS – FORENSIC PSYCHIATRY – FORENSIC PHARMACOLOGY – FORENSIC ENT/OPTHA • MEDICAL JURISPRUDENCE

• Perform autopsies and diagnosecircumstances surrounding the cause and manner of death • Determine whether death was - Accidental - Suicidal - Homicidal MEDICOLEGAL OFFICER’S RESPONSIBILITIES . Identify the deceased . Establish the TOD and DOD . Determine a medical COD —the injury or disease that resulted in the person dying . Determine the MEOD—the physiological reason that the person died . Classify the MOD - Natural - Accidental - Suicide - Homicide - Undetermined . Notify the next of kin

Person of Historical Significance

Autopsy Examination

Edmond Locard (1877-1966) . French professor . Considered the father of criminalistics . Built the world’s first forensic laboratory in France in 1910

• Autopsy means to look at oneself • Necropsy means to look at the dead • Autopsies have been practiced since the middle ages • Term autopsy generally used in Philippines

The Locard Exchange Principle

Purposes of Autopsy

• Every time an object comes into contact with another object, it either leaves a portion of itself or takes a portion of the other object with it – Every contact leaves its trace

1. determine or confirm the cause of death 2. improve the diagnosis of a specific disease 3. advance medical and scientific knowledge 4. aid in the evaluation of new techniques,procedure or medications 5. help clinicians avoid repeating errors in diagnosis and therapy in future cases 6. aid in medical education 7. may absolve guilt and remove concern about possible genetic defects.

CRIME SCENE TEAMCRIME SCENE TEAM ..A group of professional investigators, each trained in a variety of special disciplines. ..Team Members ..First Police Officer on the scene ..Medics (if necessary) ..Investigator(s) ....Medico legal Officer Or Forensic Pathologist (if necessary)(if necessary) ..Photographer and/or Field Evidence Technician ..Lab Experts Processing a body 1. Obtain victim’s clothing for more thorough analysis in lab 2. Fingernail scrapings 3. Hair sample 4. Blood sample 5. Other bio-samples 6. Hand swab (for GSR) Forensic Pathologists

Autopsy Under the Philippine System • MEDICOLEGAL AUTOPSIES • NON-MEDICOLEGAL AUTOPSIES OR HOSPITAL CASES Autopsy Process - Incisions created in chest, abdomen and head; - Removal of organs from those areas - Y or T-shaped incision is typically used, because it facilitates examination of tongue and neck - Brain is removed via incision from behind one ear to behind other ear - Scalp is pulled upward and backward - Skull is sawed circularly or in a tonsorial manner - Brain may be dissected immediately, placed in formaldehyde to preserve

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[FORENSIC PATHOLOGY ] tissue for better examination • Other internal organs are removed and weighed • Organs are also dissected to determine disease or injury • In certain cases such as child abuse, spinal injury, and subtle blunt trauma more extensive dissection and removal may be completed Obtaining Appropriate Specimens • Toxicology requires adequate specimens for testing • Blood is usually taken from aorta • Bile taken from gall bladder • Blood, urine, liver, kidney and brain used to determine presence of drugs • Blood-alcohol or Urine-drugs • Information from medical history, witness statements, scene examination, and autopsy may be used to search for other drugs or poisons Microscopic Examination • Small portions of organs are put into a solution of formaldehyde to preserve them for study • Diseased or injured sections of tissue are taken, as is normal tissue • Tissue is encased in paraffin and mounted on slides with H&E dye for examination under light microscope DNA Analysis • Preserve one specimen of tissue for DNA analysis • If tissue sits in formaldehyde for too long, DNA becomes hydrolyzed and unsuitable for study • DNA embedded in paraffin blocks or cut into sections and made into slides will not further decompose DNA Collection • Methods to accomplish this: – Blood spotted on absorbent paper allowed to dry then stored in envelope – Pull head hairs, including bulbs, and place in envelope – Cut hair has mitochondrial DNA, bulbs include nuclear DNA

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•Complete •Irreversible • The Organ Donation Act of 1991 (RA7170), as amended, defines death as “the irreversible cessation of circulatory and respiratory functions or the irreversible cessation of all functions of the entire brain, including the brain stem.” • Cardiopulmonary Death – there is an absence of natural respiratory and cardiac functions and, attempts at resuscitation would not be successful in restoring those functions. – In this case, death shall be deemed to have occurred at the time these functions ceased; or • Brain Death – there is an irreversible cessation of all brain functions; and considering the absence of such functions, further attempts at resuscitation or continued supportive maintenance would not be successful in resorting such natural functions. – In this case, death shall be deemed to have occurred at the time when these Conditions first appeared. POSTMORTEM CHANGES AND POSTMORTEM CHANGES AND TIME OF DEATH 1. ALGOR MORTIS (BODY COOLING) AND 2. RIGOR MORTIS. Body warm not stiff less than 3 hours Body warm stiff 3-8 hours Body cool stiff 8-36 hours Body cool not stiff more than 36 hours 3. LIVOR MORTIS (HYPOSTASIS, POST MORTEM LIVIDITY, POSTMORTEM SUGGILLATIONS) 4. POSTMORTEM DECOMPOSITION (PUTREFACTION) 5. ADIPOCERE 6. MUMMIFICATION 7. MACERATION 8. AQUEOUS HUMOUR POTASSIUM

Photography 9. STOMACH CONTENTS • Both film and digital photography are used, depending on law enforcement jurisdiction

10. Forensic Entomology

• Multiple photographs must be taken

11. last known activity (last sighting, newspaper/mail)

DEATH

INDIVIDUAL OBSERVATIONS USED TO ESTIMATE TIME OF DEATH

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[FORENSIC PATHOLOGY ] • When used together the following individual observations of a body may be used to estimate the time of death – body temperature – rigor mortis – livor mortis – decomposition changes – stomach contents

Bullet Entry wound – contact range star-shaped laceration Abrasion ring – contact range Bullet Trajectory -Murder

Cause of Death and Manner of Cause of Death and Manner of Death •The Cause and Mechanism of Death physiological incident which started the physical progression of death in the body.

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•The Manner of Death, on the other hand, is which category the death falls into. Manner of Death can be one of five categories: Homicide, Suicide, Natural, Accidental, or Undetermined. EVIDENCE FROM WOUNDS COMMON TYPES OF WOUNDS No blackening around entry; star-shaped, often with flaps directed outward

• CLOSE WOUND – Petechiae – Contusion – Hematoma • OPEN WOUND – Incised – Stab – Punctured – Laceration Contusions color changes a bruise goes through can give rough estimate of time of injury • Dark blue/purple (1-18 hours) •Blue/brown (~1 to 2days) •Green (~ 2 to 3 days) •Yellow (~3 to 7 days) Assumes person is healthy. BLUNT TRAUMA

Blackening around entry; grains of powder and deposits of powder residue None of the above characteristics appear

The blow produces a crushing effect Resulting in contusions, abrasions, lacerations, fractures, or rupture of vital organs.

Firearm: Contact (muzzle against body) Close (less than 18 inches) Distant (18 inches or more)

• Red-blue contusions are always present, but this varies by the weight of the individual (obese people bruise easier than lean people).

Characteristics and Type of Wound

COMMON TYPES OF WOUNDS

GUNSHOT WOUNDS

Strangulation - Ligature and Manual Mark encircling neck in a horizontal plane overlying larynx or upper trachea; sometimes broken at back of neckwhere hand grasped ligature; abrasions and contusions of skin not usually present Abrasions, contusions and fingernail marks on skin.

BULLET WOUNDS •Point of Entry and Exit Point - Bullet is spinning as it hits the body the entry area is usually smaller than the exit wound. • Bullet may ricochet inside the tissue & travels a path which is not a straight line. • Powder burns -near range hits. • contusion ring (abrasion collar) around the bullet wound usually indicates the angle and close range.

Contusion: 1 week. (Yellow green)

Defenses Commonly found on palms of hands, fingers, forearms

A BULLET PENETRATING THE SKIN

Lacerations

• When a bullet penetrates the skin: – the skin is pressed inward – the skin is stretched and perforated – the skin then returns to its original position

Open, irregularly shaped wounds, caused by clubs, pipes, pistols and other blunt instrument wounds accompanied by bruising or bleeding

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[FORENSIC PATHOLOGY ] Puncture Can be caused by ice picks, leather punches, and screwdrivers; result in small wounds with little or no blood

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Stab As above; manner in which knife is thrust into and pulled out of body can result in wounds of different shapes made with same knife

SMOTHERING

Incised Cutting wound inflicted with sharp-edged instrument, wound typically narrow at ends and gaping in middle with a great deal of blood

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Holding breath -while struggling Pink foam – exhalation of fluid. Respiratory arrest -Pupils dilate. Final struggle -3-4 quick attempts to breath.

• Obstruction of airway. If soft object e.g. pillow or blanket. No trauma. • Injury on the inner lips. • Cyanosis may or may not. • Petechial hemorrhage on the face, typically around the area of the eyes. BURN wounds

STAB WOUNDS • may be cased by heat, a chemical or electricity. • Slash wounds: cuts are as wide and they are long. look like superficial bullet wounds. Other types of slash wounds are called "hesitation marks" commonly found in suicide cases. • Incision wounds: lengths greater than their depth, greater amount of subsurface tissue is exposed in an almost oval fashion. • Puncture wound: Stab or shive wound. distinguishable by its clean-cut edges. INCISED WOUNDS • Typically bleed a lot • Are inflicted with knives or razors • Are narrow at the edges and gaping in the middle STRANGULATION • Homicidal, suicidal and accidental • PM Features: – Intensive heart congestion (enlarged heart; right side ventricle) – venous engorgement (enlarged veins above point of injury) – cyanosis (blue discoloration of lips and fingertips).

• Fire victims are often found in a “pugilistic” position with a clenched fist, resembling the pose of a boxer. • Heat generally causes the protein in the body to contract. • Blood and lung samples are often taken for various reasons. RAPE • Art. 266-A. Rape is committed – – 1. By a man who shall have knowledge of a woman under any of the following circumstances: a. through force, threat or intimidation; b. when the offended party is deprived of reason or is otherwise unconscious; c. by means of fraudulent machination or grave abuse of authority d. when the offended party is less than (12) years of age or is demented. 2. By any person who, under any of the circumstances mentioned in para (1) hereof, shall commit an act of sexual assault be inserting his penis into another person’s mouth or anal orifice, or any instrument or object, into the genital or anal orifice of another person. History and Physical Examination

AUTOEROTIC DEATH • In autoerotic death cases the investigator will typically find: – a white male partially suspended and nude – dressed in women's clothing or undergarments - or with his penis exposed. DROWNING • Rapid formation of mucus block -Bronchi. – "foam cone" covering the mouth and nostrils. – "dry drowning" -edema of Larynx -no fluid • Stages in drowning: – Surprise -Inhales water.

• A brief description of the assault indicates areas for medical investigation and treatment; recounting the events is often frightening for the patient, and a complete description may have to be deferred until immediate needs have been met. • The reasons for the questions and for the examination procedure are not always clear to patients; eg, the female patient may need to be told that knowing when her last menstrual period was or if she uses a contraceptive helps determine the risk of pregnancy or that information about the time of the previous coitus helps establish the validity of sperm testing.

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[FORENSIC PATHOLOGY ]

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• Because these patients have experienced coercion, enlisting their cooperation and requesting permission for the examination are important.

• An analysis must be performed on a stain to determine whether or not it is actually blood. If the sample is blood, the species must then be determined.

• Details of the pelvic examination should be described and explained as it proceeds, and the results should be reviewed with the patient. Because being examined by a physician of the opposite sex may make the patient feel anxious, a nurse or volunteer of the patient's sex should be present to give support and to corroborate the procedures.

• Conventional serological analysis analyzes the proteins, enzymes, and antigens that are found in blood.

• The slide demonstrates one of the best positions to examine younger children. This child is sitting on the mothers lap with the mother holding her.

• If the blood sample is human, it goes on to further identification and then individualization. • Blood analysis is a comparison analysis. The victim’s blood and the suspect’s blood must be compared to the blood found at the crime scene. • Restriction fragment length polymorphism (RFLP) DNA analysis directly analyzes certain DNA sequences found in white blood cells.

DRUG FACILITATED SEXUAL ASSAULTS • Rohypnol (street name Roofies), known as the drug flunitrazepam, belongs to a class of drugs called benzodiazepines – It produces a spectrum of effects including skeletal muscle relaxation, sedation, and reductions in anxiety • GHB. Gamma hydroxybutyrate or GHB (also known as Gamma-OH, Liquid Ecstasy, Georgia Home Boy, or Goop) – It is another central nervous system depressant that is used to perpetrate sexual assaults ROHYPNOL • Drug used by sex offenders at: – parties – bars – clubs – social drinking locations COLLECTION OF EVIDENCE DURINGCOLLECTION OF EVIDENCE DURING THE MEDICAL EXAMINATION OF RAPE VICTIM • Physical evidence to be collected: – vaginal swabs, – oral and anal swabs, – pubic combing, – head and pubic hair controls, – saliva sample, – blood sample, – fingerprint scrapings, – all clothing.

ITEMS ROUTINELY COLLECTED FROM SUSPECTS • • • •

All clothing, pubic hair combing, forcibly removed head and pubic hair controls, saliva and blood samples.

FORENSIC SEROLOGY

• Polymerase Chain Reaction (PCR) DNA analysis analyzes DNA sequences that have been replicated numerous times. This procedure works well with small samples of blood. It, however, cannot individualize a blood sample. IS THE RED STAIN BLOOD? – Benzidine color test, – Phenophthalein test, – Leukomylokite test, – Luminol test, – Microcrystalline test. SEMINAL STAINS • Seminal stains found at a crime scene are collected with cotton swab and placed in an airtight container so that they may not be contaminated. • A spermatozoa search is a microscopic analysis where sperm cells are visually observed. • The acid phospatase is a presumptive analysis that test for the general existence of semen. • Anti P-30 is a quantitative and qualitative test that identifies the presence of protein P-30 (found only in human semen). This test may also serve to individualize seminal evidence. • DNA analysis to determine if the DNA pattern extracted from a crime scene semen stain matches the DNA pattern of the suspect: – RFLP, – PCR. Maximum Reported Time Intervals For Sperm Recovery in Living Sexual Assault Victims (a) Vagina: 6-28h (motile sperm); 14h-10d (nonmotile sperm) (b) Cervix: 3-7.5d (motile sperm); 7.5-19d (nonmotile sperm) (c) Mouth: 2-31h (non-motile sperm)

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[FORENSIC PATHOLOGY ] (d) Rectum: 4-113h(non-motile sperm) (e) Anus: 2-44h(non-motile sperm) Sources of Biological Evidence Blood Semen Saliva Urine Hair Teeth Bone Tissue Perspiration Vaginal secretions

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DNA Detection • Amplified DNA fragments are labeled with a fluorescent tag • DNA fragments are separated by electrophoresis (electric current) • The size of the fluorescent DNA fragment is determined by a machine which displays the information graphically. • Analysts read the graph to determine the DNA type

The Cell

DNA Analysis

• Smallest unit of life • Compose all living things • The “nucleus” (one of many organelles) contains genetic information the cell needs to exist and reproduce -most cells organize genetic information into chromosomes

•Short Tandem Repeats (STRs) are short stretches of DNA that are repeated several times at a particular location on a chromosome

Steps in DNA Analysis collection→specimen storage→extraction→quantitation→ genotyping→interpretation of the result→ database (storage and searching)

• The number of repeats and, therefore, the length of the Short Tandem Repeat DNA varies from person to person • Each individual has two different (or two equal) length repeats at the same location on a chromosome • STR DNA testing determines the length of the STR DNA at 13 different chromosomal locations • STR DNA testing analysis is the most commonly used forensic DNA analysis method

DNA Extraction Statistics • DNA analysis begins with DNA extraction from biological evidence • DNA extraction is: – A chemical process by which DNA is released from cell(s) – Other cellular components are removed leaving a pure sample of DNA in an aqueous (liquid) solution DNA Amplification • After DNA extraction DNA is amplified using the Polymerase Chain Reaction (PCR)

• The 13 STR DNA tests produce exceedingly rare DNA profiles • A STR DNA profile might be found in 1 person out of a quadrillion (that is, a billion million) people • A match between two DNA samples, say, a crime scene stain and the DNA of a suspect, can link a subject to a crime • A non-match may shift the focus away from a particular suspect

• PCR amplification makes many copies of the DNA to allow for detection (think photocopies)

Philippine Cases -DNA

Gel Electrophoresis

• • • •

• Gel with different sized pores agarose and acrylamide are common materials

People vs. Vallejo. 2002 People vs. Yatar, 2004 Agustin vs. CA, 2005 Herrera vs. Alba, 2005

• Load DNA samples into wells at top of gel • Run electric current through the gel • DNA moves due to negative charge • Smaller bands run “faster”

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