Forensic Psychopharmacology
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Introduction to Forensic Psychopharmacology
Forensic psychopharmacology is in the simplest vernacular the merger of two disciplines: forensics and psychopharmacology. Forensics is the application of scientific knowledge and principles, from a number of disciplines, to a matter of law including criminal investigation and prosecution or civil litigation in which evidence is collected, analyzed and interpreted to ultimately render an opinion to assist in the interpretation of law. Psychopharmacology is the merger of two separate but interconnected disciplines: psychology and pharmacology. Psychology is the study of behavior and the multitude of components that ultimately lead to an action or inaction in a particular situation including psychosocial antecedents, the diagnosis of mental illness or preexisting medical conditions that contribute to or explain a behavior. Pharmacology in its generic form is the study of drugs and their actions whereas psychopharmacology is a sub-specialty focusing on psychoactive drugs, defined as drugs that change the brain to change behavior.
For nearly five decades, my professional career has focused on the interrelationship between drugs, the brain and behavior with an academic specialization in the field of alcohol studies. As an Independent Consultant in Forensic Psychopharmacology, I applied my laboratory and clinical training and experience to assist in legal matters to determine the role, if any, of alcohol (or other psychoactive drugs). For example, was the person under the influence of alcohol, either as defined by a legal statute or as defined clinically? Was the analytical methodology used in a lab to report intoxication reliable and could the analytical results or behavioral observations be affected by some physiological or premorbid psychological or medical condition? Was the cause of some event (e.g., an injury) due to intoxication or better explained by something else (e.g., mechanical failure of a vehicle, structure or machine)? The range of scientific disciplines that can be encompassed in this field of study is almost as large as the number of applications to which those fields of study can be applied. For example, the interpretation of forensic alcohol test evidence may include anatomy, biochemistry, biomechanics, chemistry, neuropharmacology, neurophysiology, physiology, psychology and toxicology to answer questions about the role, if any, of alcohol in pedestrian, bicycle, boating, drowning or motor vehicle accident, fall-down injury, overdose, or in crimes ranging from first degree murder to vehicular homicide to simple assault to medical consequences from chronic or acute high doses of alcohol that may cause organ damage or developmental changes.
Historically, the study of effects of alcohol has its earliest roots in the study of intoxicating poisons. In the most basic sense, alcohol is a poison although that definition is often lost on the general public. The term “intoxication” derived from the Greek toxikon and the Latin, toxikom, means poison. Hence, the derivation of the word intoxicated. Toxicology is the study of a wide range of poisons (e.g., from arsenic to zinc) including alcohol as a chemical toxin.
A Short History of Alcohol Use and Related Biopsychosocial Problems*
The poisonous effects of alcohol have been known at least since Biblical times. The pernicious relationship between alcohol use in pregnancy is clearly documented in the Book of Judges (13:7) which states “... behold, thou shalt conceive and bear a son; and now drink no wine nor strong drink...” It was not until the 1970s that the toxicological basis for this warning began to develop with the first reports of Fetal Alcohol Syndrome (FAS). FAS (now also called Fetal Alcohol Spectrum Disorder) results in anatomical (e.g., craniofacial dysmorphology, incomplete organ development and psychological (e.g., developmental delay, impulse control, boundary and emotional attachment) problems. Alcohol abuse during pregnancy may result in criminal prosecution of the mother who exposed her unborn child to a poison (child endangerment).
The physician-alchemist Paracelsus (1493-1541) is credited with some of the most basic concepts in toxicology and pharmacology and which are directly relevant to the forensic psychopharmacology of alcohol and other drugs. Paracelsus believed that experimentation was essential in understanding the response to toxic agents (the “toxicon”). He further proposed that there is an important distinction between the therapeutic and toxic effects of agents and that it is the dose of the toxic agents that often determines its helpful or harmful properties.
“All substances are poisons; there is none which is not a poison. The right dose differentiates a poison from a remedy.” The views put forth by Paracelsus are believed to have set the foundation for the dose-response relation, which is the basis of most studies in pharmacology and toxicology and many other services (Pachter, 1961).
In the late 18th and early 19th century, American Surgeon General Dr. Benjamin Rush put forth the somewhat radical view that alcohol intoxication, or “inebriety,” was an illness. (Jellinek, 1960). This view, and many other social and historical events eventually led to a US Constitutional Amendment that prohibited the manufacture, sale or use of alcohol. Prohibition of alcohol did not work and eventually was repealed but had an interesting consequence: it generated studies on the neurotoxic effects of a variety of toxic agents in bootleg liquor which were probably used by some advocates as further evidence to support prohibition. One such toxin was the organophosphate triorthocresyl phosphate (TOCP).
In the 19th century TOCP was an additive to Ginger Beer, a high alcohol patentmedicine that circumvented Prohibition laws. When ingested through bootleg liquor, TOCP causes a neurological syndrome commonly referred to as a “ginger-jake”, a spastic gait that’s caused by drinking TOCP adulterated ginger beer. Today TOCP is a gasoline additive (Pachter, 1961).
Throughout history, people have been aware of the potential harmful effects of drugs like alcohol but it was not until the middle of the 19th century that scientific and public interest in alcohol really began to take off. In part, this interest was precipitated by two events: the development and wide spread use of the automobile and the development of quantitative methods of analysis for alcohol.
Certainly by the mid 1800s, concerns about safety and alcohol intoxication were already forcing changes in law and public policies. For example, the New York Central Railroad prohibited employees from drinking on the job as early as 1843. Apparently the problem of intoxicated railroad employees was so great that in North America “Rule G” was adapted by the American Railway Association in 1899. Rule G prohibited drinking by railway crewmembers while on duty. By the turn of the last century, research using quantitative methods of analysis of alcohol and the effects of alcohol on the body was gaining momentum. But it was not until the early 1900s there was enough data to correlate measured amounts of alcohol in the body with impaired behavior. E.M.P. Widmark, a Swedish physician, was probably the first person to develop a protocol to evaluate suspected drunk drivers. Some of Widmark’s “diagnostic factors” are still used today by police and clinicians to assist in determining if someone is intoxicated.
In the United States, a U.S. Army physician, Dr. Herman Heise, was responsible for performing autopsies of soldiers who died in automobile crashes “after a night on the town”. Heise observed that the majority of soldiers were “heavily loaded with alcohol.” After finishing his tour of duty in the Army, Heise returned to Uniontown, Pennsylvania where he worked with Pennsylvania State Police to develop a drinking-driving protocol much like the one developed by Widmark in Sweden. Some elements of their early protocols are still used by police today.
For the most part, forensic alcohol test evidence will be collected at the request of law enforcement. The collection of intoxication test begins with observations of motor vehicle operation or of alcohol containers in a vehicle that has been stopped or that has been involved in an accident and continues with observations of individual witnesses or suspects.
The Necessary Merger of Multiple Scientific Disciplines
Forensic alcohol evidence relies upon contributions that follow the merger of various disciplines to provide the most accurate and comprehensive evaluation of test evidence. For example, a chemist or toxicologist is often involved in quantifying the amount of alcohol in a sample of blood or other tissue. A law enforcement officer, or clinician (psychologist or psychiatrist), is often required to make observations and interpret behavior to determine if someone is intoxicated and impaired by alcohol. A chemist or toxicologist who measures alcohol (or other drugs in tissues or bodily fluids) and interprets those findings without consideration and training in behavioral sciences or physiology may not recognize exculpatory symptoms or review medical evidence of impairment produced by factors unrelated to alcohol intoxication. For example, endocrine, neurological disorders or hepatic diseases may produce behaviors that mimic intoxication and may explain a discrepancy between objective and subjective evidence. Similarly an expert in medical physiology or behavioral sciences may not recognize a problem in the analytical measurement of alcohol before attempting to interpret other evidence. Consideration of many factors from different disciplines provides the most accurate reconstruction and interpretation of forensic alcohol evidence.
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Since alcohol is overwhelming represented in fatal and serious bodily injuries secondary to motor vehicle crashes, both criminal investigations as well as civil litigation often require a reconstruction of the accident to determine the cause of a vehicle leaving the roadway and crashing, for example. At the very least, accident reconstructionists, usually engineers or police with highly specified training in automotive mechanics and in the application of Newtonian physics to answer the question, would a crash have occurred regardless of intoxication or did intoxication affect perception and reaction time and other human factors that are required to reconstruct an accident. Let’s take a closer look at how knowledge from specific disciplines can be merged to understand the effects of alcohol.
Anatomy, Histology, Pathology
Alcohol use can have both acute and chronic effects, depending on dose and duration of use as well as individual anthropometrics. Although acute alcohol use and intoxication does not appear to permanently affect cell structure, chronic alcohol use can produce long term changes in cells that form organs or glands. How does this relate to the forensic examiner’s investigations? The chronic effects of alcohol may be of interest to the examiner seeking to determine any pre-morbid factors that would aid in the interpretation of both behavior and in some cases, physiology. For example, it is well known that heavy consumption of alcohol during pregnancy increases the risk for a constellation of behavioral and morphological symptoms (Fetal Alcohol Spectrum Disorder – FASD). There is now evidence suggesting that the impulsive, sometimes uninhibited behavior exhibited by children and adults with FASD may be due to specific structural changes in the brain areas such as the corpus callosum, a bundle of fibers that connect the left and right hemispheres of the brain. In a case in which alcohol intoxication was established in a person with FASD, was the behavior due to intoxication, changes in brain structure due to FASD or both?
Chronic heavy alcohol abuse can also produce structure changes in the central and peripheral nervous system. For example, alcohol can damage the cerebellum resulting in permanent ataxia. Since the cerebellum is an important brain structure in smoothing out motor movement commands from the cortex, similarly chronic alcohol abuse can affect the peripheral nervous system (peripheral neuropathies) that also affect gait. Therefore, consideration must be given to determine if the impaired motor movement detected in a person who consumed alcohol is due to intoxication or nervous system damaged due to chronic heavy alcohol abuse?
Microscopic examination of liver samples taken at autopsy and properly stained, may reveal stenosis (fatty infiltration), or cirrhosis (cell death) offering a clue regarding the decedent’s previous history of alcohol use or justifying the need for pharmacokinetic assumptions outside any “average” (e.g., rate of alcohol elimination). Similarly, the identification of non-alcohol related hepatitis would preclude conclusion about prior alcohol use.
Chemistry
Analytical chemistry plays a significant role in forensic alcohol analyses by providing the foundation for the identification and quantification of alcohol in body fluids and tissues. Beginning with the pioneering work of Nicloux (circa 1896) in France, Widmark (circa 1912) in Sweden, Borkenstein (circa 1950s) in the US, and continuing through the modern era, analytical chemistry has been particularly helpful in quantifying breath and blood alcohol and allowing scientists to correlate these findings with behavior, risk, injuries and other areas of interest to the general well being and safety to the public.
Hospital enzyme tests, police breath testing, laboratory gas chromatography are all based on different chemical principles and are used daily in the measurement of alcohol to assist in diagnosis, treatment of clinical observations.
Physiology
Principles in biology and physiology are important in accounting for differences in absorption, distribution, elimination and pharmacokinetic analyses of alcohol. For example, liver damage from disease may affect alcohol metabolism, whereas a diabetic in medical distress may appear intoxicated and have an alcohol-like odor on their breath due to the release of ketones (ketoacidosis). Differences in the respective water contents of blood, serum or plasma may similarly affect alcohol concentrations in those samples. Such physiological changes must be considered to avoid misinterpreting forensic evidence.
Physics and Engineering
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The use of basic principles in physics is invaluable in the reconstruction of many accidents. For example, when a vehicle crashes, it brings with it into that collision elements of speed, momentum and energy. The use of Newtonian physics helps determine the speed, momentum, energy and path of the vehicle, along with other factors that can reconstruct the point at and the manner by which a vehicle lost control. When human factors (including perception and reaction time) and mechanical factors (including stopping distances and time to stop) are combined with biobehavioral effects of alcohol such as changes in attention, reaction time, and proprioception, the manner the events that immediately preceded the crash can be better determined.
Psychology
Psychology is the study of behavior, its causes, diagnosis, treatment and understanding of internal and external factors that ultimately affect and predict human behavior. There are many subspecialties within the field of psychology, relevant to forensic aspects of alcohol intoxication. For example, clinical psychologists (and psychiatrists) engaged in the treatment of behavioral disorders are trained in the diagnosis of general mental illnesses and may also have specialized training in the diagnosis of alcohol intoxication, abuse or alcohol dependence. Their diagnoses also includes consideration of different Axis as described in the Diagnostic and Statistical Manual of the American Psychiatric Association. Experimental psychologists have contributed to various areas of understanding with regard to the effects of alcohol through the design and execution of various psychophysical tests involving perception and reactin time. In fact, the first psychology laboratory in the world founded by Wilhelm Wundt (1832-1920) in Leipzig Germany (1879) was devoted to sensory processing and mental processing through the study of reaction time, which is a key component of motor vehicle operation and accident reconstruction. Reaction time is the time that passes between a stimulus and a response and is an important part of accident reconstruction. Biological or physiological psychologists have multidisciplinary training in pharmacology, neurochemistry, and other neurosciences as well as psychology. Psychologists are also trained in learning and motivation that is important in understanding non-pharmacological forms of alcohol tolerance. A biological psychologist may apply all of the above training to study the biological basis for changes in the nervous system result in various behaviors, including those produced by alcohol intoxication or the interaction of alcohol and other psychoactive drugs.
Pharmacology and Toxicology
General principles in pharmacology and toxicology also play an important role in forensic alcohol analyses. When applied to forensic alcohol test evidence, these principles allow for accurate estimates of blood alcohol concentrations, how much alcohol was consumed, determining the distribution and elimination of alcohol and bringing objectivity to the often variable evidence that comes from subjective reporting. In recent years, training in toxicology has included topics such as “performance” toxicology incorporating findings from other disciplines (e.g., psychology) to relate behavior to objective chemical or toxicological test results.
In the last few decades our understanding of the mechanisms through which the drug alcohol changes the brain to change behavior has come largely from neuroscience and neuropharmacological research. Thus, it is apparent that understanding and interpreting alcohol intoxication evidence involves education and training in a number of overlapping disciplines, not one specific field. When possible, practical clinical experience combined with laboratory training will be particularly useful in the forensic examination of alcohol intoxication evidence.
The above discussion is derived from several publications, including:
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Brick, J., (2017) What is Forensic Alcohol Test Evidence? In: Forensic Alcohol Test Evidence, (pgs 3-9) Charles Thomas Publishing
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Brick, J. and Erickson, C. (2009) Identification of Alcohol Intoxication: A Prevention Challenge, Alcoholism: Clinical and Experimental Research 33(9) 1489-1507