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A Vision of the Future by Steven I. Friedland  Excerpted from
Steven I. Friedland is a Professor of Law at Nova Southeastern University Law Center in Florida. He studied law at Harvard and Columbia Universities.
The Human Genome Initiative, also called the Human Genome Project, commenced in 1988 with an announcement by Nobel-laureate scientist James D. Watson. It was intended simply as a science project, albeit one on a grand scale. Indeed, the concerted effort to map and sequence the approximately 100,000 genes of human DNA has become "the largest biology project in the history of science." The project was expected to last up to two decades, involve scientists from many countries, and cost approximately three billion dollars.

While the focus of the initiative is to identify, record, and sequence genes,the objectives of the project extend well beyond scientific curiosity. The advancement of genetic knowledge could be used to combat disease, effect human physiology, manipulate psychology, and much more. Some scientists have gone so far as to claim that the project is "the ultimate answer to the commandment, 'Know thyself.'"

Despite an inability to predict the course of the human genome project,tremors from its discoveries are already being felt in the legal system,particularly in the area of criminal law. In some ways, the seeds of a"geneticized" criminal law system already have been sown. For example, many jurisdictions permit the utilization of DNA "fingerprinting" at trial, and genetic disorders are increasingly being offered as defenses in criminal cases. Believing that some people are born with criminal tendencies and therefore cannot be rehabilitated, many jurisdictions have adopted a "three strikes, you're out" approach to sentencing. Laws requiring the detention of sexual predators are grounded on similar beliefs. Indirect genetic links between crime and conditions such as alcoholism and antisocial behaviors have been established, and genetic explanations already have been offered to exculpate the accused at trial. Some knowledgeable observers believe thereal question "is not whether genetic evidence will ever be admitted into court, but when and under what kinds of circumstances."

A genetically based system might have the following features. The new system would shift the focus from a normative, psychological imperative, which determines culpability largely based on an individual's mental state, to a genetic, physiological orientation. Genes would play a larger role in determining the propensities of behavior and the scope of criminal responsibility. For example, people with "aggressiveness genes" might be expected to act more aggressively and therefore would be treated differently than those who do not have such genetic abnormalities. Genetics would be offered as a defense to criminal charges and create forensic work for expert witnesses in the field. Genetic information might serve to predict the future dangerousness of an accused. Finally, genetics would be offered as an exculpatory factor in sentencing decisions and gene therapy would become an option in the rehabilitation of convicted criminals.

A genetically based criminal law system, however, may produce turbulent and troublesome consequences. The traditional formulation of the criminal law has been based on the concept of free will, which presumes that behavior is volitional. People are generally thought to be autonomous and responsible for their own conduct. The notion of free will lies at the core of any criminal "blameworthiness" decision. However, genetic discoveries will impact the presumption of free will. Such discoveries will affect not only general issues of culpability, but also the use of genetics as a defense at trial, the relevance of genetics in predicting dangerousness in pretrial or post-trial release decisions, and the use of genetics as a mitigating factor in sentencing decisions.

Perhaps the most significant product of a system reordered on the basis of genetics would be the resurrection of biological determinism, a theory that attributes much, if not all, of a person's behavior to external causation.This shift in paradigm from free will to some form of determinism - either a "weak" determinism, in which genes play only a factor in behavior, or a "strong" determinism, in which genes are a causal agent of behavior - would create pressure to reinvent the current understanding of criminal responsibility. For example, defendants may claim their genes "caused them" to commit the crime and "blame" would be attributed to unthinking, unknowing cellular DNA. The trend would be exacerbated as public zest for genetics increased.

Genetic determinism could lead to the conviction or acquittal of people based on their physiological status rather than on their actions. Genetic information could be used to classify individuals based on the type of genetic risks they pose, particularly their level of dangerousness. In addition, a new type of discrimination may result from the creation of genetic "minorities" as people are grouped by their genetic propensities. On a broader scale, the emphasis on genetics may serve to diminish traditional functions of the criminal law, especially the provision of a moral baseline of behavior for the community. . .

The Reconstruction of a Genetics-Enhanced Criminal Justice System

If the discoveries of the Human Genome Initiative reveal that genetics play a large role in determining human behavior, the impact will be far-reaching. A genetically reordered system would revolve around a biological basis ofconduct, rather than the psychological basis of the current system. With more than two thousand diseases already shown to have originated from single gene defects, it might well be a logical projection to expand the reliance on genetics as a source for defining behavior. The presumption of free will would dissipate in light of evidence to the contrary.

Support for a genetic reordering already can be found in empirical studies. Research has indicated the existence of a correlation between biological conditions and criminal behavior, although the linkage is insufficient to show causation. In a recent publication of the journal Science, Dutch researchers claimed to have discovered a genetic link to violent behavior. They studied several generations of a Dutch family that had exhibited significant levels of antisocial and criminal behavior. The researchers found that members of the family were deficient in a particular enzyme, monoamine oxidase A ("MAOA"), associated with levels of the neurotransmitter serotonin in the brain. They concluded that there was a link between this genetic abnormality and the family's antisocial behavior. One of the researchers stated, " 'It was always clear that genetics was involved in behavior. . . . But this is the first example showing a specific gene that changes the behavior of individuals.'"

In another study, researchers examined mice with an MAOA deficiency. Just like the family in the Dutch study, MAOA-deficient adult mice exhibited excessively aggressive behavior. In another study of mice, it was found that males who lacked the gene that produces nitrous oxide were more prone to violence. Several significant studies of twins also have been undertaken. "Twin studies" are significant because twins often are raised in a common environment and generally have the same genetic compositions.

Some researchers suggest that the limbic area of the brain is responsible for violent behavior. The limbic brain houses the amygdala, which is important in the control of such emotions as fear and anger. The "flight or fight" mechanism in animals also marked early humans, and only as civilization has advanced has such a response become "seen as antisocial and maladaptive." Some researchers have concluded that the small group of individuals who commit the majority of crimes have a genetic marker causing them to act in a violent manner.

Taking these studies of the limbic brain one step further, scientists have examined the relationship between biology and human conditions such as addiction, personality disorder, and antisocial behavior. While no specific genes were isolated that proved to be the causal agents of these conditions, the scientists did conclude that genetics influenced an individual's propensity for antisocial behavior. For example, sociopathic, alcoholic fathers were twice as likely to have children exhibiting sociopathic behavior than parents without such attributes, and psychopathic fathers were more likely to have psychopathic children.

Claims of a link between genetics and behavior have been made in many other areas, including "mental illness, homosexuality, aggressive personality, dangerousness, job and educational success, exhibitionism, the tendency to commit arson, stress, risk-taking, shyness, social potency, traditionalism, and even zest for life." Experts have suggested that mental illnesses such as schizophrenia could have genetic origins. As one commentator noted, "Remarkably, schizophrenics who have been deaf from birth claim to 'hear' voices, providing strong evidence that there really is a brain malfunction involved." . . .

Perhaps the most important among the many changes likely to occur in a genetics-based system is a reemergence of determinism as an overarching theme of the criminal law. Determinism can be roughly defined as a philosophical doctrine that suggests that actions can be explained by prior causes. The antithesis of determinism is free will, which is based on the tenet that individuals have the power to determine their own behavior. While few would suggest that genes alone determine a person's behavior, the criminal law would become more like psychiatry, which "purports to be rigorously scientific and therefore takes a determinist position. Its view of human nature is expressed in terms of drives and dispositions which, like mechanical forces, operate in accordance with universal laws of causation. " The real question would be: How much determinism? Whether a strong form of determinism, yielding the conclusion that genes actually cause behavior, or a weaker form, where causation is interdependent on genes and environmental factors, prevails, may prove to be a matter of degree or a question of interpretation. How deterministic human behavior really is could be the focal point of many future debates. . .

Genetic "character evidence" would differ from traditional character evidence in at least one major way: its permanency. Traditional character evidence is transitory, since it is premised on the belief that people can change. Biological explanations, on the other hand, particularly those rooted in genetics, presumably do not change. If genes are "all-powerful," human beings could be reduced to their genetic codes. With the increasing number of discoveries about genetics, it is easy to understand why the populace may be persuaded that "genes control everything." . . .

Propensity determinism would impact many specific areas of the criminal law. The most significant areas, however, would probably be in the areas of defenses to crimes and sentencing decisions. In both contexts, genetic predispositions could serve as mitigating factors in judicial determinations. While such evidence might not stand alone, it could be the most significant of the mitigating factors, particularly in a serious case in which the accused is facing the death penalty. . . The Supreme Court has consistently stated that the prediction of dangerousness is not so random as to be excluded from courts of law. . .

A genetically reordered system would greatly extend this trend toward pre-conviction predictions of dangerousness and the association of mental illness with criminally violent conduct. Under the new system, persons would be classified according to their genetic predispositions to violence. The degree of aggressiveness evidenced in a person's genetic predisposition, coupled with other "abnormal" genetic traits or "mental abnormalities," would play a major role in questions of pre-trial release, character evidence at trial, post-trial release, sentencing, and parole. The perceived dangerousness of a person might be modified by conduct that defied his or her genetic "scorecard," but that "scorecard," much like blood type, would be permanent.

The subsidiary effects of this new system would be plentiful. The police would create new strategies of investigation based on the genetic propensities of suspects. When pulled over for speeding, an individual could be asked for a driver's license, registration, and genetic propensities card. When a fight at a bar occurred, the investigating officers could run a genetics check on the participants. Discovery of an accused's genetic propensities would be sought in a wide variety of criminal cases and be made available through computer files for fast, nationwide referencing. A cadre of "dangerousness" experts, ready to testify about their expertise at trial, would develop. This group would offer a different approach to dangerousness than that of the psychologically oriented psychiatrists and psychologists of today. At sentencing, the length of the defendant's sentence might be affected by his or her "dangerousness quotient." Rehabilitation would be relegated to an official secondary status and would be oriented toward those individuals whose genes indicated they could be most influenced by environmental factors. Incarceration would be recognized for what it has already become in many settings merely a means of separating dangerous individuals from the rest of society. Genetic predispositions would also become increasingly important at the parole stage,while the prisoner's conduct in prison would lessen in importance. . .

Sentencing generally permits consideration of mitigating factors. These factors cover a wide range of possibilities. There is no reason the possibilities ought not include genetics. The "story" of the crime may include genetic syndromes and propensities. If genetic influences affect behavior, genetics may not only provide an explanation, but also offer a means of preventing repeat crimes. In the same vein, family history would gain increasing importance as further evidence of a genetic predisposition. The prosecution and defense would evaluate the family history not only in the context of sentencing, but also for determinations of dangerousness, charging decisions, and genetic defenses at trial. Genetic "reconstructionists," the equivalent to accident reconstructionists, would build a genetic family history to support a biological theory of the defendant's or victim's conduct. These experts could testify at trial about genetic causes and effects.

Deterministic Defences

Another subsidiary effect of propensity determinism is the use of genetics as a defense to a crime. While prosecutors would use genetic information to prove their cases, defense counsel would attack the scientific analyses as flawed. The scientific validity of the genetic information might be questioned based on the currentness or accuracy of the data upon which the calculations are based or the procedures might be attacked if they were performed under poor or imprecise conditions. Further, the credibility of the scientists would be attacked for bias and interest.

The traditional common law presumed that behavior was volitional, but with genetic discoveries, this presumption likely would no longer be valid. Instead, in a genetically focused system, proof of voluntariness by the prosecution may be required. If a prima facie case of voluntariness is made by the prosecutor, a plethora of newly created defenses should be available to defendants based on genetics. Individuals would claim that their genes caused their behavior, so they should be exonerated from criminal liability. Juries would be forced to evaluate how much of a person's behavior was attributable to genetics - and biological determinism - and how much was volitional. Thus, fact issues would be transposed to center on questions of causation. . .

The use of scientific evidence and theory about genetics would promote inefficient short-cuts of several kinds. Eventually, these short-cuts would stimulate the recreation of discretionary, moral approaches to the criminal law. Scientific analysis has credibility with the public because it is reproducible, predictable, and apparently objective. Great deference has been accorded to the scientific method and the scientists who perform it. Yet simply because science can offer an answer to a question does not mean it is the "right" answer. This is especially true in the context of the criminal justice system, where the centerpiece of "justice" has not been reducible to quantitative analysis in the past. While the public may desire formulaic and quick answers to questions about facts and guilt, attempts to generalize scientific evidence may be problematic on several levels. Scientists may be prematurely pressured to produce or generalize their findings, particularly if their research is the subject of considerable publicity. Further, scientific studies often are not ready for generalization. . .

Propensity determinism could be used to assist those who suffer from violent predispositions. Yet, it might also lend itself to racism and discrimination in several pernicious way. . . The alleged nexus [between crime and genetics] appears to offer an invitation to discriminate and to stereotype "genetic minorities." The mere creation of criminally suspect groups has several damaging consequences in addition to the obviously improper criminal "class system" that would develop. Such a biological approach would lead to the failure to closely scrutinize environmental factors such as child-rearing practices, schooling, and cultural influences, and may even overlook differences in genes - from mutations to latency to interactive questions - within the labeled group. As a senior fellow at The Hoover Institution recently noted, even "within every race, there are genetic differences among individuals and families." Extrapolation of any genetic information may include biases and prejudices, rendering "objective" genetic information "subjective."

An individual inclined to crime because of his or her genes could be tracked by methods similar to the current computer software programs police use to track arrest and bench warrants, criminal records, stolen cars, and the like. The genetic basis for the grouping would suggest that the organizational scheme is objective, without human biases and prejudice. Yet, the selection of individuals for tracking and investigating would still retain the human element, and there may be a greater degree of reliance on rounding up "the usual (genetic) suspects." . . .

DNA fingerprinting is often used by prosecutors or defense attorneys in establishing the guilt or innocence of a defendant accused of a crime. This most often occurs in sexual batteries. For example, in March 1990, a conviction was overturned because genetic fingerprinting showed that the defendant was not the perpetrator. . . In the reordered system, DNA fingerprinting would occur as a matter of course, and the procedures used in the testing would be more difficult to challenge given the frequency of use and the probable standardization of methods. DNA data would still be challenged on statistical grounds, given that the fingerprinting does not provide an absolute identification. However, this undoubtedly would not deter prosecutors, jurors, and the public from relying on the information. Thus, several important byproducts might result. For example, trials would appear to become scientific endeavors, dominated by scientific witnesses and terminology. Jurors might defer to these experts more than they already defer to experts and would perhaps even abdicate their responsibility to review the evidence and determine the facts. Most significantly, eyewitness testimony may be accorded less importance, particularly if DNA evidence offers fewer doubts about its accuracy. Individuals who proclaim their innocence, and even those who offer their guilt, can be tested almost immediately to avoid miscarriages of justice. DNA identification cards may be developed along with "genetic propensity" cards and may be as common as Social Security numbers in identification endeavors. .

The Public Backlash

Even an administrable genetically reordered criminal justice system likely would suffer from a backlash. Unrealistic expectations by the public would be vetted by some scientists making unsupported claims and others who expose such claims. Conversely, public outrage may be kindled by the commission of morally reprehensible acts by individuals who are excused due to genetic defenses. These occurrences are likely to foster a revival of the social construction of the criminal law.

Public reaction would demand increasing scrutiny of the processes used by labs in their genetic research, including DNA research. While convictions have been overturned based on DNA testing, the trend is for prosecutors to proceed with a case despite DNA tests that indicate the accused did not commit the crime charged. Some prosecutors deny DNA tests are dispositive of guilt or innocence, especially since the science is still evolving and not fully understood.

Additionally, just as the backlash after the John Hinckley trial triggered a reworking of the insanity defense in many jurisdictions, so too would the acquittal of a person charged with a particularly heinous crime based on a genetics defense or the conviction of a person with a high propensity to violence who later was shown to be innocent. The reworking would involve a narrowing of the genetic attribution of criminal behavior.

This backlash would increase the level of skepticism surrounding the use of statistical probabilities to predict behavior, and provoke a renewed examination of environmental variables or simply a greater adherence to a belief in free will. The most explosive area in the free will debate, however, may involve "the alcohol factor." Scientists have found that the risk of alcoholism is linked to genetic make-up, and that some individuals, "because of inherited factors, are biologically and behaviorally different from individuals who have few or no inherited factors that predispose them to alcoholism." Instead of excusing or even explaining criminal conduct caused or promoted by the consumption of alcohol, society's intolerance with alcohol-related conduct may spur a revised responsibility for avoiding the first drink, thereby reintroducing free will even though part of the conduct may be "genetically involuntary."


The criminal justice implications of the Human Genome Project are significant. From a revision of the definition of criminal responsibility, to predictions of dangerousness, to expert testimony on genetically caused behavior, many areas of the criminal justice system will be influenced by the Human Genome Initiative. Through a process of reimagining a genetically reordered system, the true extent of the changes that might occur are revealed. In the end, such a system would not necessarily perform better, and deference to genetics discoveries and scientific "short-cuts" would be counterproductive. It becomes clear that the criminal law is socially constructed to serve society as a democratic institutional tool, and that moral blameworthiness is its yardstick. The scientific approach would try to hide this moral yardstick without offering an acceptable substitute. Thus, a genetically reordered system would create different problems rather than solve existing ones. The lesson to be learned is that science may be appropriate in certain contexts and circumstances, but it is not the panacea for the legal system's ills. Eventually, even the new genetically reordered system would be transformed and recreated to once again embrace the concepts of free will and moral blameworthiness. By exploring the ramifications of a genetically reordered system, however, it becomes apparent that only through the criminal law's own evolution will it avoid falling inexorably behind in creating a coherent and suitable approach to useful and dangerous genetics advances and evade the temptation to use genetics and science as a substitute for the necessary and imprecise social aspect of the criminal law.

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