FORENSIC PATHOLOGY

IZABELA DEMBOWSKA-CZUBATYINTRODUCTION TO FORENSIC SCIENCES

DEATHCAUSE OF DEATHNATURAL no disease, no injury, recently quite uncommonDISEASE out of the interest of forensic medicine and prosecutionINJURY remains in the scope of interest of prosecution (homicidal, accidental and suicidal)

TIME OF DEATHSUDDEN no agony, usually injuriesSLOW with agony, usually diseases, rarely injuries

DEATHMANNER OF DEATHACCIDENTALSUICIDALHOMICIDALNATURAL

DEATHSTAGES OF DEATHFALSE DEATH (vita minima) a person is still alive but living functions remain on a very low levelCLINICAL DEATH a person can be still brought to life (no heart beat, no breathing)BRAIN DEATH allows for the announcement that the person diedINTERLETHAL STAGE brain is damaged but some functions of body can be observed (growth of hair and nails)BIOLOGICAL DEATH inevitable damage to cells

DEATHCONDITIONS OF DEATHRIGOR MORTIS LIVOR MORTISALGOR MORTIS PALLOR MORTIS discoloration (white) of skin

DEATHRIGOR MORTISThe muscles of the body initially become flaccid after death. Within 13 hours following death, the muscles begin to become noticeably increasingly rigid and the joints immobile (freeze) due to a process known as rigor mortis (postmortem rigidity, rigor). When a body stiffens, it remains in that position until rigor passes or it is physically overcome (broken), such as when a joint is forcibly moved. Since the chemical process of rigor is irreversible, fully developed rigor will not recur in an area in which it has been broken or in an area in which it has already passed.

DEATHLIVOR MORTISLivor mortis (postmortem hypostasis, lividity) is the discoloration of the body after death due to the gravitational settling of blood which is no longer being pumped through the body by the heart.Livor mortis is usually noticeable approximately 1 hour after death and is often apparent earlier, within 2030 minutes. The discoloration increases in intensity and usually becomes fixed in about 810 hours. The formation of livor may be hindered or prevented by pressure applied to the bodys surface because the small blood vessels become compressed and blood is prevented from settling into them.

DEATHALGOR MORTIS (body cooling)After death, the body equilibrates with the surrounding environmental temperature. Although this usually involves algor mortis (cooling of the body), in some cases, such as a body laying on a sidewalk in direct sunlight, the body may absorb heat. However, in most cases, the body will progressively lose temperature until it equilibrates with its environment. Many studies have examined this progressive decrease in body temperature to attempt to develop formulae which could be used to calculate the postmortem interval.

DEATHDRYINGdryingautolysis damage of the cell structuresrotting (green discoloration)adipoceremummificationdecomposition in peat bogs

ROTTINGThe environment is a major determinant of the type of decomposition the body undergoes and the rate at which it proceeds. Bodies that are buried in earth, submerged in water, left in the hot sun or placed in a cool basement will not look the same after the same postmortem interval.In general, as rigor passes, green discoloration of the skin becomes evident. The green discoloration typically begins on the abdomen and then spreads to the rest of the body. At room temperature, the right lower abdomen turns green at about 24 hours after death and the entire abdomen is green by 36 hours. As with other postmortem changes, the onset and progression of the green discoloration is quite variable.

ADIPOCEREAdipocere is a term derived from Latin which literally means fat (adipo) wax (cera). It refers to a hard gray-white waxy substance formed during decomposition. It is an uncommon change, occurring particularly in bodies buried for an extended period of time in cool, moist environments and is most commonly seen after bodies have been submerged in water during the winter months. Not all bodies having adipocere are found in water. For example, bodies found in plastic bags which provide a moist environment may also undergo this change.

MUMMIFICATIONMummification occurs in hot dry environments where the body is able to dehydrate and bacterial proliferation is minimal. The skin becomes dark, dry and leathery. The internal organs desiccate and shrink. Most mummification occurs in the summer months but may also occur during the winter if the temperature is warm enough. An entire body can mummify in a few days to weeks. As the skin dries and hardens, the soft tissues decompose. After a few weeks, an entire body may appear preserved with some shrinkage due to dehydration.

DEATHDETERMINATION OF DEATHconditions of deathinterlethal signsgastric contentsbleeding level

EXAMINATION OF BODYEXTERNAL EXAMINATION OF BODY at the crime scene

INTERNAL EXAMINATION OF BODY autopsy

EXTERNAL BODY EXAMINATION

order of eventspeople involved in examinationa scope of activities that may be conductedpreservation of evidence at the crime scene

INTERNAL BODY EXAMINATIONTYPES OF AUTOPSY (legal reasons)scientific forensicTYPES OF AUTOPSY (time)before body is burriedafter exhumationTYPES OF AUTOPSY (purpose)determination of the cause and manner of deathgrafting of internal organs

INTERNAL BODY EXAMINATIONAUTOPSY PURPOSESdetermination of the cause and manner of deathdetermination of the time of deathdetermination of injuriesdetermination of tools that may have caused injuriesdetermination of the circumstances of death

THANK YOUMaterials prepared basing on: Jay Dix, Michael Graham, Time of Death, Decomposition and Identification. An Atlas, CRC Press 2000.

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