The World of Forensic Medicine in Harris County

By Luis A. Sanchez, M.D.

The Harris County Me-dical Examiner’s Office is located in the Joseph A. Jachimczyk (JAJ) Forensic Center in the Texas Medical Center at 1885 Old Spanish Trail. The Office includes postmortem investigations (pathology service) and the analytical support services provided by a fully accredited laboratory. The Office’s mission is to provide Harris County residents with (1) accurate scientific determinations of the cause and manner of death of individuals dying violently or suddenly and unexpectedly, and (2) accurate scientific analysis of evidence submitted to the forensic crime laboratory. “Quality” has become a priority to ensure that forensic investigation is carried out in an efficient, unbiased, and thorough manner in alignment with national forensic investigation standards. This article provides an overview of the duties and responsibilities of the forensic disciplines, the resources and expertise available at the Office to the legal community, and the Office’s legal responsibility for determining the cause and manner of death.

History
The Harris County Commissioners Court established the office of the Medical Examiner in 1957. Pursuant to article 49.25 of the Texas Code of Criminal Procedure, Commissioners Court appoints the Medical Examiner (“ME”) who serves at its pleasure.
In 1960, Dr. Joseph A. Jachimczyk became Harris County’s first Chief ME. Dr. Jachimczyk’s innovation and foresight in the area of forensic pathology helped to establish the Office’s national reputation. In 1986, the controlled substance laboratory was established for forensic purposes and pre-employment drug testing for Harris County law enforcement. Gunshot residue analysis was added in 1987. In 1988, serology, hairs and fibers, and urine testing were instituted. In 1991, the Office added laboratory facilities to include criminalistics, electron microscopy, teaching, and research, and the DNA laboratory was opened in 1994. Dr. Jachimczyk retired in 1995.
In 1996, Dr. Joye M. Carter became the second Chief ME, and the first woman to head a Texas medical examiner’s office. She served from 1996 to 2002. During her tenure, the DNA laboratory was reorganized and revamped with new technology.
After a few months as interim Chief ME, in 2003, Dr. Luis A. Sanchez became the third Chief ME for Harris County. Dr. Sanchez has expanded the number of Office employees, created standard operating procedures for operations, and ensured accreditation by national boards.1

Duties
Pursuant to the Texas Code of Criminal Procedure, certain categories of death must be reported to the Medical Examiner Office2, including (1) deaths within 24 hours of admission to a hospital, or in jail or prison; (2) deaths from any unnatural cause (except under sentence of the law); (3) when a body is found and the circumstances of death are unknown; (4) when there is a suspicion that a death was from unlawful means; (5) suicides, or suspicion thereof; (6) deaths unattended by a physician and deaths in which the physician is unsure of cause of death; and, (7) a child younger than six years when there is suspicion of abuse and neglect.
The MEs certify the cause and manner of death, performing autopsies when necessary to make such determination. In 2004, the Office investigated 12,270 deaths, accepted jurisdiction in 4,165, and performed 2,923 autopsies and 1,242 external examinations. The Office serves the community by promoting public health and safety, and by educating the public and other professionals about proper death investigation and the principles of forensic medicine and science.
Autopsy. An autopsy is an examination of a dead body. In the course of an autopsy, the body is examined multiple times: as it is received, after it is unclothed, and after being cleaned (any loose dirt, blood, or other foreign substances are removed). At each step, any identifying features, injuries, or other unusual features are documented with multiple modalities (i.e., photographs, dictation, and/or diagram). The body is then opened and each organ is examined, in turn, for the presence of injuries or pre-existing natural disease.
In the course of an autopsy, samples of various organs, tissues and body fluids are retained for additional ancillary studies, if warranted. The ancillary studies include microscopic examination (histology), drug testing (toxicology), and microbiology (bacterial and viral culture). Additionally, depending upon the type of case, other items of evidence may also be retained, such as foreign objects (bullets, knife blades or tips, ligatures, etc.), scalp hair (for comparison to hair on a suspect weapon or vehicle), fingernail scrapings (for analysis of blood and/or foreign DNA), sexual assault swabs, gunshot residue test swabs, and so on. The Office is also very active in the collection of trace evidence from dead bodies (collected under visible and alternate light sources).
External Examination. An “external examination” of the deceased is a postmortem examination limited to external findings and review of available medical records and investigative information to arrive at the cause and manner of death without internal organ examination/evisceration. While fluids (blood and vitreous humor) are typically retained and submitted to the toxicology laboratory, toxicology testing on external examinations is rarely requested except as indicated by the pathologist, who also may request radiographs to assist in evaluation of clinically diagnosed injuries.
Partial autopsies (e.g., “head only,” “thoracic organs only”) are not performed at the Office. Any case requiring invasive examination (i.e., involving incision of the head or thoracoabdominal cavities) must undergo a complete autopsy.
Cause of Death Determination. The determination of the cause of death can be straight-forward or may be more complicated, requiring the assistance of toxicology tests, laboratory reports, hospital records, histology examination of tissues, and other studies. The determination of the cause of death may occasionally take months to complete.
The cause of death is the disease or injury responsible for initiating the lethal sequence of events. When there is a delay between the onset of a disease process or injury and the ultimate death of an individual, the proximate (also known as underlying cause) and the immediate cause of death must be distinguished. The underlying or proximate cause of death is that which, in a natural and continuous sequence unbroken by any efficient intervening cause, produces the fatality and without which the end result would not have occurred. Immediate causes of death are the sequelae (or complications) of the underlying cause that precede death. There may be one or more immediate causes, and they may occur over a prolonged interval, but none absolves the underlying cause of its ultimate responsibility. For example, a man sustains a transabdominal gunshot wound with perforation of the colon. In spite of treatment, over a period of three months he develops peritonitis (localized infection of the abdominal cavity), and septicemia (infection spread into the circulatory system-blood). Because such infection is a reasonable and foreseeable consequence of an abdominal wound, the proximate cause of death is the gunshot wound. In this instance, the infections are regarded as dependent on (i.e., the gunshot wound) as the intervening factor, which, within a reasonable degree of medical probability, caused the death of that person at that time. The importance of this concept is that it allows one to form a conclusion as to the manner of death and, in this instance, allows for criminal prosecution of homicide. When the injury results in immediate death (e.g., gunshot wound to the head), the distinction between proximate and immediate causes of death does not apply, they are essentially the same thing.
Manner of Death Determination. The manner of death as expressed on a death certificate is primarily for vital statistical purposes and refers to a general classification of the nature of the cause. The manner of death can be determined based on probability derived from the preponderance of evidence and available knowledge of the case. If pertinent information or evidence is obtained after the initial determination, the manner of death may be amended, even if the cause of death remains unchanged.
The Office recognizes five classifications of the manner of death, in accordance with the format of the Bureau of Vital Statistics. They are: (1) natural; (2) accident; (3) suicide; (4) homicide; and (5) undetermined (“could not be determined” on form). Natural deaths are defined as those caused exclusively (100 percent) by disease. Deaths involving any trauma are considered “violent” and include accident, suicide or homicide. The “undetermined” classification may apply to violent deaths or to deaths that appear natural, but cannot be confidently classified as non-violent due to circumstances.
The classification of a case as homicide by the ME can be misunderstood. We follow the following rule: when death occurs as the result of the deliberate action of another, the manner of death (for the death certificate) is classified as homicide. The key phrase is “deliberate action” and it must be distinguished from “accidental,” “intentional,” and “unintentional.” Intent is not a prerequisite for classifying a death as a homicide. Rather, intent is the purview of the courts, and the degree of intent will determine if the homicide is excusable or justifiable, or whether it is a murder. Culpability is the province of the courts and will be determined by subsequent criminal and judicial proceedings, not by the ME.
For motor vehicle fatalities, the manner is typically assigned as “accident,” unless clear homicidal or suicidal intent is demonstrated by the driver of the vehicle responsible for the collision. This practice is primarily for uniformity of vital statistical data and has no bearing on criminal actions, nor does it represent an opinion as to the legal responsibility of the offending driver (e.g., driving while intoxicated, failure to stop and render aid).

The Office’s Divisions
Forensic Pathology Service. The pathology service is staffed by nine full-time physicians who are specially trained in the field of forensic pathology and two physicians (fellows) who are in training in forensic pathology. Their duties include performing autopsies to determine the cause of death and manner of death. However, their most challenging task is to identify, document, and preserve everything of a potentially evidentiary nature. In addition to their work in the autopsy room, they juggle a busy schedule that includes traveling to the scene of some deaths; teaching at the forensic center, medical schools, law schools and hospitals; and testifying in court.
Forensic Investigative Division. The Office’s investigative unit is comprised of forensic investigators, forensic nurse investigators, and administrative assistants. Forensic investigators conduct death investigations by developing organized, concise, and accurate death reports.3 Forensic investigators may respond to the scene of a death and document the scene with photographs, measurements, temperature readings, and written documentation. While in the field, forensic investigators may also conduct a preliminary physical examination of the body, including collecting and preserving physical and biological material at the scene for evidence, or for further forensic investigation. The forensic investigator prepares and submits all specified reports and may testify in court regarding scene investigation, observations, and investigative reports.
Forensic Nursing. In 2003, the Office incorporated forensic nursing as a new area of expertise for the investigative division. The Office has the first and only team of forensic nurses in Texas who are specialized in death investigation. Forensic nurses are specially trained to combine the forensic aspects of health care with practical nursing and apply that knowledge in the scientific death investigation of victims and/or perpetrators of violence, criminal activities, and traumatic accidents. The forensic nurse complements the forensic investigator, resulting in an improved investigative process while enhancing interaction among community agencies. The forensic nurse also provides a vital link between the investigative staff and the pathologist.4

Harris County Crime Laboratory
The crime laboratory is nationally accredited, and all current testing capabilities and methodologies are approved by the accrediting boards.5 The forensic laboratory provides analytical support for the Harris County MEs and law enforcement agencies. In 2004 the forensic laboratory completed approximately 41,000 cases and provided over 400 hours of expert testimony. The crime lab is comprised of the following disciplines: quality assurance/quality control; biology (serology and DNA); toxicology; controlled substance; trace evidence; and, histology.
QualityAssurance/QualityControl. The quality assurance/quality control staff ensures that the Office maintains accreditation standards and ensures that the DNA section complies with appropriate accreditation standards.6 The laboratory and its personnel are regularly evaluated for analytical capability and proficiency in the different areas in which forensic examinations are performed, and also for compliance with the policies and procedures specific to each section. To remain current with the latest advances in forensic science, laboratory staff members participate in regional and national professional organizations and meetings.
Forensic Biology Division (Serology and DNA). The biology section screens evidence for the presence of body fluids such as blood, semen, saliva and, sometimes, urine and feces. Positive samples identified by serological methods are then retained for DNA testing. The DNA section extracts DNA from evidentiary samples and conducts a DNA analysis. The biology section helps solve crimes by comparing the DNA profile of evidence samples collected from crime scenes to that of known individuals. This DNA information is also used for body identification and for establishing paternity.
Toxicology. Members of the toxicology section combine expertise in chemical analysis with their knowledge of drug pharmacology, metabolism, and pharmacokinetics to analyze and interpret the effects of drugs found in forensic specimens. The activities of the toxicology section can be divided among four principal areas:
Postmortem toxicology analyzes the presence and amounts of alcohol, drugs, and other potential poisons in postmortem tissues. These analyses help MEs to determine the cause and manner of death under investigation and assist law enforcement agencies in the investigation of drug- or alcohol-related crimes.
Toxicology analyzes beverages and blood or urine specimens that are submitted after DUI or DUID arrests to determine alcohol and/or drug content. These analyses are applied to the prosecution of these offenses.
Toxicology analyzes specimens submitted during the investigation of drug-facilitated sexual assaults. Specimens such as blood, urine, or beverages are tested for common or uncommon “date rape” drugs such as gamma hydroxy butyric acid (GHB) and flunitrazepam (Rohypnol).
Forensic urine drug testing analyzes urine specimens for drugs of abuse such as alcohol, amphetamines, cocaine, opiates, marijuana and phencyclidine (PCP). These tests are provided to Harris County law enforcement agencies as employee screens and to Harris County Court Services.
Controlled Substance. The controlled substance section performs analysis and identification of any suspected controlled substances that are submitted to the forensic laboratory from Harris County and federal law enforcement agencies Drugs can be submitted in the form of powders, liquids, plant-like materials such as mushrooms, and illicit pharmaceuticals such as tablets, capsules, liquids, and injectables.
Trace Evidence. The trace evidence section analyzes gunshot primer residue by scanning electron microscopy (SEM)/electron dispersive analysis by x-ray. Ascertaining the presence of gunshot primer residue is based on detecting the presence of antimony, barium, and lead found in most gunshot primer residues. Gunshot residue analysis using the scanning electron microscope provides state of the art automated analysis. This section also performs hair screening for DNA, and examines unknown samples submitted by the controlled substance section using the SEM to determine the elements (i.g., potassium, biodine, etc.) present. Finally, the trace evidence section collects trace evidence from bodies in the morgue and at a crime scene, and collects trace evidence from items submitted to the laboratory.
Histology. At the time of autopsy, the effects of many disease processes, injuries, and toxic effects are readily recognizable with the naked eye. However, some pathological changes will require microscopic examination for recognition or to provide adequate documentation. For organs to be examined under the microscope, a small sample (“biopsy”) of each organ must be chemically processed, mounted on a glass slide, and appropriately stained. The Office employs histotechnologists to process these tissue samples for microscopic examination by the pathologists. The histotechnologists also play an active role in the archiving of glass slides, “wet tissue” samples, and other anatomical specimens as may be deemed necessary for civil or criminal litigation.

Final Comment
During the last two and half years, the Office’s current administration has undertaken a comprehensive effort to improve the effectiveness and efficiency of the forensic center. The Office has succeeded in acquiring the very best in physicians, scientists, laboratory personnel, cutting-edge equipment, trained investigators, administrative staff, and support staff. The Office has maintained and gained new accreditations to validate that the services provided to the residents of Harris County are in alignment with the national standards for death investigation. The Office has strong academic affiliations with local medical schools, reflecting Dr. Sanchez’s philosophy that the Office must maintain a level of academia to guarantee that our practice is cutting-edge, up-to-date, and grounded in unbiased science. The new administration has demonstrated its commitment to maintaining the neutrality of the Office in its role of criminal investigation and civil litigation by encouraging prosecutors and defense attorneys to consult with our experts before trial. The Office has also taken an active role as a teaching center by creating unique learning opportunities for the entire legal community, both prosecution and defense. Thanks to the professionalism of the Office personnel and the steadfast support of Commissioners Court, Harris County has an academically-oriented forensic center delivering first-rate service to the community.

Endnotes
1. The Office is currently accredited by the American Society of Crime Laboratory Directors/ Laboratory Accreditation Board (ASCLD/LAB), Department of Public Safety (DPS), American Board of Forensic Toxicology (ABFT), and the Accreditation Council for Graduate Medical Education (ACGME). 2. Texas Code of Criminal Procedure article 49.25, section 6. 3. Texas Code of Criminal Procedure article 49.25. 4. Some of the duties of the Office’s forensic nurses are to:  (1) conduct death scene investigations with emphasis on infant deaths; (2) collect evidence in cases of suspected sexual assault and child abuse; (3) review medical records and obtain additional test results required by the pathologist; (4) provide case management for complicated cases; and, (5) collaborate with organ and tissue procurement agencies in order to determine appropriate release of organs and tissue. 5. The lab is accredited by the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB) and the American Board of Forensic Toxicology (ABFT). 6. The DNA lab is accredited by the FBI Quality Assurance Standards for Forensic DNA Testing and Convicted Offender DNA Databasing laboratories.

Dr. Luis A. Sanchez is the Chief Medical Examiner for Harris County. Dr. Sanchez received his medical degree from The University of Massachusetts in 1988.  He then specialized in anatomic pathology at Columbia University College of Physicians and Surgeons in New York City and in forensic pathology at the Dade County Medical Examiner’s Office in Miami, Florida. He is board certified in both disciplines.

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