Massachusetts Criminal Lawyer Explains: Autopsy Basics
A medico-legal autopsy – an examination of the body after death – is conducted in cases in which the circumstances of the death suggest that the death was caused by homicide, suicide or accident. No consent from the family is required to perform a medico-legal autopsy. To defend a client charged with murder, a criminal defense lawyer needs to fully understand how an autopsy is performed and how a medical examiner reaches his conclusions.
The terms medical examiner, pathologist, and coroner – although not necessarily synonymous – usually refer to a physician charged with determining the cause of death. The autopsy ideally includes both a thorough external examination of the body and a probing examination of the internal organs of the body. During the external examination, the pathologist combs the body searching for wounds and injuries, noting deformities, absence of limbs, state of nutrition, and unusual features. The pathologist will examine the hands, fingers, fingernails, feet, teeth, scalp, tattoos, scars, hair, skeleton remains, hair fibers, jewelry, and clothing. While conducting the internal examination, the pathologist will remove the deceased’s chest plate, lungs, heart, liver, intestines, etc. and, with the use of a scalpel, examine these organs for wounds, disease, and deformities.
The medical examiner’s office may videotape the autopsy and will release a report detailing its findings, including the cause of death. Autopsies, as well as the reports released by the medical examiner, vary in quality. Some medical examiners take little care in their work. A small percentage are outright incompetent. For the Massachusetts criminal defense lawyer representing a client charged with murder, the autopsy may prove pivitol to the defense. If there is any reason to suspect that the deceased died from something other than the alleged actions of the defendant (i.e., natural causes) or in a manner incompatible with the theory of the prosecution, the lawyer should retain the services of a medical examiner to carefully review the autopsy results and, if necessary, perform a second autopsy. While it is the prosecutor’s obligation to prove how the alleged victim died, a competent criminal defense attorney recognizes that he must thoroughly review the autopsy findings for mistakes, errors in judgment, and faulty conclusions.
What Might an Autopsy Reveal?
Determining the Time of Death
Especially where a client charged with murder has an alibi, an accurate estimate of the time of the death may prove critical to the defense. An experienced criminal defense attorney will direct his forensic expert to independently approximate the time of death.
The time of death can, with variable accuracy, be estimated by determining:
1. the temperature of the body and the rate of cooling;
2. the degree of postmortem lividity (hypostasis);
3. the degree of rigor mortis;
5. insect activity; and,
6. analyzing stomach contents
Rate of Cooling: The normal temperature of a living person is 98.6°. During first hour following death, the body temperature will drop 2° to 3° F. Thereafter, the body temperature will fall 1° to 1.5° per hour, for up to 18 hours. Naturally, the rate of cooling will be influenced by many factors, including the temperature of the air surrounding the body, the amount and weight of the clothing worn by the deceased, and the age and size of the deceased.
Hypostasis is the gravitational pooling of blood into the dependent areas of the body. The distributional pooling of the blood is determined by the position of the body following death. Once the blood has pooled, blood clots form preventing the blood from re-pooling elsewhere if the body is moved. Therefore, lividity or discoloration caused by the pooled blood may reveal whether a body has been moved following hypostasis. Because the rate of lividity or hypostasis varies from body to body, it not considered, by most medical examiners, as an accurate methodology for calculating the time of death.
Rigor Mortis is the stiffening of the muscles caused by chemical changes occurring in the body following death; Every muscle in the body undergoes rigor mortis. Stiffening begins within two to five hours after death. The entire body will be rigid within 12 to 18 hours of death. Thereafter, rigor mortis begins to dissipate and, within another 18 hours, the rigor mortis will disappear and the body will, again, resume a relaxed state. Rigor mortis should not be confused with cadaver spasms, which may cause stiffening of the body immediately following death.
Putrefaction: Once the respirations cease and the cells of the body are no longer being nourished, the cells die and so begins the process of decomposition. Microorganisms, the temperature surrounding the body (particularly heat), and the exposure of the body to air and moisture (water, humidity) contribute to decomposition. Bacteria, always present in the body, will invade the cells following death. Autolysis, the softening and liquification of tissue, is caused by the digestive action of enzymes released from dead cells. Both bacteria and autolysis convert the soft tissues of the body into fluids and gases.
Insect Activity can accelerate the rate of decomposition. Insects not only eat the flesh of the deceased, but often lay eggs on the body. Because entomologists are familiar with the time that it takes for a particular insect to emerge from its egg and develop into an adult, an entomologist can assist the medical examiner in estimating the time of death by collecting and examining the eggs, larvae, pupae and adult insects present on or about the body.
Insect activity, together with warm and moist conditions, can rapidly destroy the body of the deseased. In Commonwealth vs. Ronald Allard: Massachusetts Criminal Defense Attorney Kevin J. Mahoney’s client was accused of murdering the man who had stolen his fiancé away. Following the alleged deadly encounter, the client allegedly hid the body beneath some leaves, etc., in the woods during a hot, humid summer. When the body was recovered only 11 days after the victim had been last seen, most of the internal organs of the body – including the heart, lungs, and brain – had already disappeared in the decompositional process.
Stomach Contents: Estimating the time of death by examining the stomach contents is not, because of the variability in the digestion process, regarded as a very reliable method for estimating the time of death by knowledgeable forensic experts. Criminal defense attorneys should be prepared to vigorously challenge “time of death” estimates based on the digested remains of the deceased’s last meal.
Autopsy: Searching for a Suspected Poison
Murder by poisoning is rare and often difficult to prove. If the medical examiner suspects murder by poisoning, he will collect several specimens from the body of the deceased. These biological specimens will be forwarded to the State Crime Laboratory and, if results are needed immediately, to a private laboratory for testing. Laboratory technicians, chemists, or toxicologists will subject the specimens to various toxicology testing methodologies. If poisoning is suspected, but the poison is unknown, the lab will test the specimens for a wide variety of poisons. The labs will often use quick, inexpensive, unreliable screening tests to determine the possible presence of the particular chemical/poison in the specimen. Screening tests, such as radio immunoassay, enzyme immunoassay and thin-layer chromatography are often very sensitive, but not very specific. Because they are very sensitive, they will very likely detect the chemical/poison if it is, indeed, present in the sample. Unfortunately, because they lack specificity, they are given to false-positives – mistaking a substance with a similar chemical make-up for the suspected poison. Unless the results of these screening tests are confirmed with a reliable testing methodology, such as gas-chromatography/mass-spectrometry, the results of these screening tests do not satisfy the evidentiary standards for admissibility.
Embalming, obviously, interferes with the ability of the medical examiner to identify the cause of death. The embalmer, after removing blood and other fluids from body, pumps embalming fluid – principally formaldehyde – into the body cavity and circulatory system. The embalming fluid slows down the decomposition process.
Even where the State Crime Laboratory has detected the suspected poison, the medical examiner can often do no more than estimate the quantity of the poison from the toxicology testing results. Because post-mortem decomposition can artificially elevate the quantity of the suspected poison detected, an inexperienced, irresponsible, or untutored medical examiner may mistakenly characterize a non-fatal dose of “poison” as the cause of death.
Commonwealth vs. Christina Martin: Attorney Mahoney overturned Ms. Martin’s conviction for first-degree murder by demonstrating that the toxicology methodologies utilized by the Massachusetts Crime Laboratory and the Medical Examiner’s Office had detected not LSD – the suspected cause of death – but an ingredient in the embalming fluid.