Neuroethics

, Volume 1, Issue 3, pp 205–212

Psychopathy and Criminal Responsibility

Article

DOI: 10.1007/s12152-008-9021-9

Cite this article as:
Morse, S.J. Neuroethics (2008) 1: 205. doi:10.1007/s12152-008-9021-9

Abstract

This article considers whether psychopaths should be held criminally responsible. After describing the positive law of criminal responsibility in general and as it applies to psychopaths, it suggests that psychopaths lack moral rationality and that severe psychopaths should be excused from crimes that violate the moral rights of others. Alternative forms of social control for dangerous psychopaths, such as involuntary civil commitment, are considered, and the potential legal implications of future scientific understanding of psychopathy are addressed.

Keywords

Psychopathy Legal responsibility Criminal responsibility Antisocial personality disorder Rationality Coercion 

Introduction

Psychopathy is a disorder characterized by emotional abnormalities, such as lack of empathy, conscience and concern for others, and by conduct abnormalities, such as repetitive antisocial behavior. It is estimated that 25% of convicts serving prison terms suffer from psychopathy, which is a substantial risk factor for crime. The law’s response to psychopathic criminals is therefore an important moral and practical policy issue. In particular, should the law hold psychopaths criminal responsible? If so, how should psychopathy be taken into account at sentencing. If not, are there sensible alternative means to address the potential harms psychopathy produces?

This article begins by considering the criminal law’s current positive theory of responsibility. It demonstrates that the capacity for rationality and the absence of coercion are the two most generic responsibility criteria and that the lack of rational capacity and coercion are the two most generic excusing conditions. It then turns to the current criminal law response to psychopaths, which is to hold the psychopath entirely criminally responsible and not subject to involuntary civil commitment. Next, it offers an alternative normative account that would excuse psychopaths from criminal responsibility for criminal offenses that are also violations of the moral rights of others. The article then considers alternative mechanisms of social control if some psychopaths were to be excused for criminal conduct. Finally, it addresses the potential contribution scientific discoveries could make to legal policymaking and practice.

Psychopathy must be distinguished from Antisocial Personality Disorder (APD), which, unlike psychopathy, is a diagnostic category included in the American Psychiatric Association’s authoritative Diagnostic and Statistical Manual of Mental Disorders, 4th Ed-Text Revision [DSM-IV-TR]. All but one of the criteria for APD are repetitive antisocial behaviors, and the one psychological criterion, lack of remorse, is not necessary to make the diagnosis. About 40–60% of prisoners have APD and there is substantial overlap with psychopathy. Despite inclusion of APD in DSM-IV, there is great controversy about whether as defined it should be considered a mental disorder. Psychopaths, by contrast, lack psychological attributes that seem central to successful, cooperative life. This paper assumes that criminals with APD are responsible because APD is not inconsistent with current or normatively defensible responsibility criteria. Psychopathy will therefore be the focus of the paper.

Preliminary Observations About Legal Responsibility

The law’s view of the responsible person generally and all its criteria for criminal responsibility specifically are resolutely folk psychological. Mental states and actions are the crux. It is important to understand that free will–understood as metaphysical libertarian freedom–is not a criterion for any criminal law doctrine, and, on a compatibilist interpretation of the metaphysics of responsibility, it is not even foundational for criminal responsibility. Indeed, the law’s positive criteria for criminal responsibility are not inconsistent with the truth of determinism. Moreover, causation per se of criminal behavior, including causation by abnormal variables, such as brain pathology, is not an excusing condition. Various causes might explain why a genuine excusing condition, such as lack of rational capacity, is present, but the law will excuse only if the folk psychological excusing condition is in fact proven. The law also adopts what I have termed “desert-disease” jurisprudence for deciding how to respond to potentially dangerous individuals [1]. With limited exceptions that need not concern us, the law does not permit pure preventive detention of individuals solely on the ground that the agent may pose a risk of harm. But if a person has committed a crime and is responsible, the person may be criminally blamed and punished because the agent deserves such treatment. Further, if the agent is dangerous because he or she is not responsible for the potential dangerousness–say, the person suffers from a delusion that renders him dangerous–then the state may civilly confine the person. In sum, the state can blame and punish a responsible agent who commits a crime and can involuntarily civilly confine a dangerous agent who is not responsible for his or her risk to others.

The Positive Law of Criminal Responsibility

The structure of the American law of criminal responsibility is facially straightforward. Crimes are defined by their criteria, which lawyers refer to as the “elements” of crime. The most important elements are a prohibited act and an accompanying culpable mental state (mens rea). For example, a traditional definition of murder is the intentional killing of a human being. The act is any form of killing conduct, such as shooting or stabbing. The mens rea is the purpose to kill that accompanies the killing conduct.

The definition of every crime requires an act (or an omission when there is a duty to act). Despite the centrality of this requirement, the law’s definition of an act is somewhat obscure because it does not provide a positive definition of an act. Rather, it tends to define what is not an act. One may infer, however, that the underlying definition is an intentional bodily movement performed in a state of relatively integrated consciousness. The meaning of intentional in this definition is narrow and means nothing more than a “willed bodily movement.” Another way of understanding this requirement is that the movement is “volitional.” It does not mean that the defendant acted for any particular reason. For example, completely habitual movements are considered acts.

The mens rea terms, such as purpose or knowledge, have their ordinary meanings. They do not include the capacity for moral reflection nor a requirement that the defendant acted “whole heartedly.” An ambivalently formed or held intention is nonetheless an intention.

If the prosecution can prove the definitional elements beyond a reasonable doubt, prima facie criminal liability is established. Unless psychopaths suffer from some other abnormal condition, there is no reason to believe that in general they do not act or cannot form the mental states the law requires when they commit crimes. In short, it will seldom be difficult to establish the psychopath’s prima facie criminal liability.

Even if the prosecution can prove all the elements beyond a reasonable doubt, however, the defendant may still be able to establish some other defensive claim that is independent of doubt about the prima facie case requirements of an act and mental state. These defenses are called “affirmative defenses” and may usefully be categorized as justifications and excuses. In cases of justification, conduct that is otherwise criminal is under the specific circumstances considered right or at least permissible. For example, a person who saves his own life by killing a wrongful deadly aggressor properly acts in self-defense although he kills intentionally. Note that in cases of justification there is nothing “wrong” with the agent. He acts rightfully or permissibly under the circumstances. Excuses exist when the defendant’s conduct is undeniably wrongful, but the defendant is not considered a responsible agent. For example, the defense of legal insanity may excuse a defendant who kills an innocent victim because the defendant suffers from a delusional belief that the victim intends to kill the defendant. Psychopathy has nothing to do with justification per se, so the question will be whether evidence of psychopathy will help to support a legal excuse.

The best interpretation of the criminal law’s generic responsibility criteria are that the agent has sufficient rational capacity and does not act under coercion. Correlatively, the law’s generic excusing and mitigating conditions are lack of rational capacity and coercion. The law clearly employs an everyday, common sense notion of rationality, but how much rational capacity and what kind are necessary are thoroughly normative judgments and are seldom clearly specified. For example, one test for legal insanity is whether the defendant knew what she was doing. This is a rationality test, to be sure, but it does not specify how narrowly or broadly knowledge should be understood. Consider Andrea Yates who drowned her five children to save them from Satan’s eternal torments. Did she know what she was doing? Narrowly, it seems that she did because she knew she was killing her children and that it was illegal to do so. But broadly, it seems that she did not because she did not understand that killing the children would not save them from Satan’s eternal torments. At this point, it is sufficient to recognize that lack of rational capacity is the primary excusing condition. It explains why some people with mental disorders, young children, people with dementias, and the like are either excused or mitigated if they commit crimes arising from their impaired practical reasoning.

The second generic excusing condition is coercion, which arises much less frequently. Note that if the defendant does not act at all because someone literally moves the defendant’s body in a prohibited way, the defendant will not be prima facie liable. Assuming that the defendant acted, the most common doctrinal expression of a coercion excuse is “duress.” Duress obtains if, through no fault of his own, the defendant is placed in a threatening, do-it-or-else situation–say, someone threatens to kill the defendant unless the defendant kills an innocent third party–and a person of reasonable firmness would have yielded to such a threat under the circumstances. The defendant need not subjectively feel fear or “irresistible” psychological pressure (although most doubtlessly will). It is sufficient if a reasonable person would have yielded. The interesting, normative question, is what we expect of “reasonable” people under such circumstances. Again, this is a normative question.

A fraught question for the law is how to understand claims that the defendant could not help or control himself in situations in which no one is threatening the defendant. Familiar examples of such one-party “coercion” claims are addictions and untoward sexual desires, such as pedophilia. What does it mean, independent of problems with rational capacity, to say that a person cannot help or control himself? Difficulties conceptualizing and assessing such problems are central reasons why “control” tests for excuse in these one-party cases are less common than tests for lack of rational capacity.

In short, it should be clear from this brief summary of the law that the crucial category for assessing the criminal responsibility of psychopaths will be the excuses, and lack of rationality in particular.

Current Legal Response to Psychopathy

As the introduction indicates, this section will be exceedingly brief. The law does not excuse psychopaths, even those whose psychopathy is clear and severe. Psychopathy is not a legally sufficient basis to raise an insanity defense or any other excuse. Indeed, the influential Model Penal Code specifically excludes psychopathy as a legally sufficient mental abnormality for its version of the insanity defense [2]. To the extent psychopathy is considered at all in sentencing, it will virtually always be considered an aggravating factor, such as using it as a risk factor for dangerousness in capital sentencing. Moreover, psychopathy per se is not considered a legally sufficient mental abnormality to support involuntary civil commitment.

The question for the law is whether these responses are correct, questions that can be asked as a matter of criminal law theory and practice. It is to these questions that this paper now turns.

Psychopathy and Criminal Responsibility

At least in theory, and mostly in practice, our criminal justice system assumes that no one should be blamed and punished unless the agent deserves blame and punishment. The law also has consequential justifications for criminal punishment, such as prevention, but desert is at least a necessary justification.

By definition, an agent who is not morally responsible for behavior does not deserve moral blame and punishment for it. Legal and moral responsibility criteria need not coincide, however, and as a positive matter, they do not. Indeed, the degree to which moral and legal responsibility should be identical is of course controversial. Our criminal law contains numerous instances of strict liability in which punishment, often potentially severe, is imposed without any proof of moral fault. For example, a defendant may be convicted and punished for statutory rape of a completely consenting partner if the partner is under a certain age, even if the defendant thought the partner was older and every reasonable person would agree. For the most part, however, as we have seen, the doctrines that excuse or mitigate criminal responsibility–lack of rational capacity and coercion–closely track the variables commonly thought to create moral excuse or mitigation. I shall therefore assume that the criminal law should not blame and punish agents who commit serious crimes unless those agents are morally at fault because they are responsible.

The justification for the law’s view that psychopaths are responsible may be briefly stated. First, as we have seen, psychopathy does not prevent agents from acting as the law defines action, nor does it prevent psychopaths from forming prohibited mental states. A psychopath who kills another human being intentionally is fully prima facie criminally responsible. Further, psychopaths are not excused because they do possess many rational capacities. They usually know the facts and are generally in touch with reality, they understand that there are rules and consequences for violating them, which they treat as a “pricing” system, and they feel pleasure and pain, the anticipation of which can potentially guide their conduct. This is a relatively thin conception of rational capacity, but the law deems it sufficient to justify punishment on desert and deterrence grounds. Finally, psychopaths do not suffer from lack of self-control as it is traditionally understood. They do not act in response to desires or impulses that are subjectively experienced as overwhelming, uncontrollable or irresistible. Once again, there is no need to excuse according to either a desert or deterrence justification for punishment. In short, the law views the psychopath as bad, and not as mad.

In contrast, I believe the law’s assessment is morally incorrect and should be reformed. Psychopaths are not morally responsible and do not deserve blame and punishment. There are two potential theories for why this should be so: a specific and a general theory concerning the psychopath’s rational capacities.

The specific theory concedes the law’s thin view of the psychopath’s rational capacities, but suggests that the psychopath has particularized deficits of rationality when moral concern and respect for others is in question. As a normative matter, the best reasons people have for not violating the rights of others are that the potential wrongdoer fully understands that it is wrong to do so and has the capacity to empathize with the potential pain of their possible victims and to use that as a reason for refraining. If a person does not understand the point of morality and has no conscience or capacity for empathy, only fear of punishment will give the person good reason not to violate the rights of others. As has been recognized at least since Hobbes, however, social cooperation and safety cannot be secured solely by the fear of state punishment. Internalized conscience and fellow feeling are the best guarantors of right action. The psychopath is not responsive to moral reasons, even if they are responsive to other reasons. Consequently, they do not have the capacity for moral rationality, at least when their behavior implicates moral concerns, and thus they are not responsible. They have no access to the most rational reasons to behave well. This position has been adopted in various forms by many philosophers [3].

The broader theory, most ably advanced by Paul Litton, [4] denies that psychopaths are rational at all because they lack any evaluative standards to assess and guide their conduct. The do not even possess evaluative standards related to the pursuit of excitement and pleasure. Psychopaths are like Frankfurt’s concept of the “wanton.” They do not feel regret, remorse, shame, and guilt, feelings that are typically experienced in reaction to our failure to meet the standards we have set for ourselves. They may feel frustration and anger if they fail to get what they want, but these are not reactive emotions. Such frustration or anger does not entail negative self-evaluation. Moreover, severe psychopaths are out of touch with ordinary social reality. They say that they have goals, but act in ways inconsistent with understanding what having and achieving a goal entails. They do not consistently follow life plans and are impulsive. Litton concludes that “it is not surprising that agents with a very weak capacity of internalizing standards act on unevaluated whims and impulses.” [4] Much of their conduct appears unintelligible because we cannot imagine what good reason would motivate it. In brief, psychopaths have a generally diminished capacity for rational self-governance that is not limited to the sphere of morality.

I am unconvinced by the broader view. Many of the broader irrationality characteristics may be present in some psychopaths, but they are not core characteristics. I also believe the argument understates the psychopath’s capacity for some evaluative standards and reactive emotions. In contrast, the moral incapacities appear to be core. These are empirical quibbles, however, and future research may clarify the diagnostic characteristics of psychopathy. The broader view is nonetheless plausible and coherent at present, and it does furnish another rationality-based theory for potentially excusing psychopaths.

On either view, the psychopath is not a member of the moral community, is not a person with whom moral engagement is possible. Again, psychopaths know the facts and the rules and are capable of manipulation of others to achieve their own ends, but they do not get the point of morality. It is as if they are color blind to moral concerns. The rights and interests of others have no purchase on their practical reasoning. Blaming and punishing such people is morally pointless, although it may be instrumentally warranted. Whether psychopaths should be blamed and punished is a question of how we want to live together. Because psychopaths are not members of the moral community, I believe that they should not be held responsible.

If this argument is convincing, the appropriate legal response is to broaden the mental disorder criterion of the insanity defense to include psychopathy as a sufficient mental abnormality to support the defense and to broaden the cognitive criterion to include lack of moral capacity. The excuse would only apply, however, to crimes that prohibit immoral behavior. The law treats strict liability crimes purely as pricing mechanisms and there is no reason to treat the psychopath differently from ordinary people when such crimes are prosecuted. Moral concern plays no role in understanding and obeying such prohibitions. Psychopathy is a continuum concept so all psychopaths would not have to be excused. Severe psychopathy would be excused, however, and individual jurisdictions would have discretion to decide whether less severe psychopathy should also excuse. My preference would be to excuse only severe psychopaths. Those with less severe conditions who retain residual moral capacity, albeit weak, would still be considered members of the moral community and subject to blame and punishment.

An interesting issue is whether psychopaths would also meet the criteria for “control” tests for legal insanity, such as the inability to conform one’s conduct to the requirements of law. As discussed earlier, it is hard to make good sense of control tests, [5] but psychopaths do not feel allegedly “overwhelming urges” or “irresistible impulses.” If they have trouble controlling their desires to act antisocially, I believe it is because they cannot access the good reasons not to. In short, for psychopaths (and others) failures of self-control collapse into rationality deficits. As we will see presently, the problem of control does arise in the involuntary commitment context and will be discussed in somewhat more detail below.

A potential objection concerns people whose acculturation, rather than biological or psychological abnormalities, may deprive them of particularized rather than general moral concern. For example, rabid racists may be genuinely incapable of empathy or conscience towards despised groups, but may retain a general capacity for empathy and conscience. Political fanatics may be similar when dealing with their supposed enemies. Moreover, such people may acquire such attitudes and predispositions when they are children and thus before the age of reason and responsibility. One could claim that they ratify and endorse such predispositions as adults, but that simply avoids the difficult question of how to respond to such people when they victimize the despised “other.” After all, shedding one’s deepest attitudes and predispositions may be beyond the capacity of most people. How does one learn to love or even to have concern for a person an agent believes is “subhuman” or entirely unworthy of concern? I believe that this is a difficult problem for responsibility theory.

“Acculturated psychopaths” should be held responsible because they do have the general capacity for conscience and empathy and they do understand that other people believe that members of the despised groups are worthy of empathy and concern. They do understand the moral point of the prohibition against harming the despised other, even if they cannot feel it. The law may only be a “pricing mechanism” for them when the rights of despised victims are violated, but, unlike pathological psychopaths, acculturated psychopaths are members of the moral community who in principle do understand and can be taught to respond to the good reason to widen their view of humanity. If this approach to acculturated psychopaths is unpersuasive, then such people should also be excused from crimes committed against the despised other. There would be no reason to excuse them from other crimes, however.

Defendants acquitted as legally insane are committed to mental hospitals for evaluation, treatment and incapacitation. They may be held indefinitely until they are no longer either mentally abnormal or no longer dangerous [6]. Moreover, the Supreme Court of the United States has made clear that it is constitutionally acceptable to consider minor property crime as sufficiently dangerous to continue such commitments [7].

At present, psychopathy is not a treatable condition, so all psychopaths who commit non-trivial crimes would be subject to potentially life-long involuntary civil commitment if they are excused by reason of legal insanity. Such a response would clearly be a potential civil liberty and fiscal problem. Psychopathy is a risk factor for crime, but many might not re-offend despite their mental abnormality. The prediction of future antisocial behavior is a difficult enterprise and often creates large numbers of false positive predictions, especially for low base rate behavior. Moreover, the potential extreme loss of liberty seems in many cases disproportionate to the potential risk to society that many psychopaths might pose. Finally, civil commitment is very expensive. In sum, the remedy of civil commitment may seem worse than convicting psychopaths. This is a serious practical problem.

If only severe psychopaths, those with essentially no capacity for conscience and empathy, were excused, the problem would be manageable. The number of excused defendants would be relatively small and many could be released when they “age out” of the stage of life when the risk of violence is high. Psychopaths are deterrable and presumably they would not want to risk further indefinite incarceration. I assume that, like other mentally abnormal defendants, most psychopaths who are charged with minor crimes that carry minimal prison terms would choose not to raise the insanity defense because a minimal prison term would be preferable to indefinite civil confinement. If successful biological or other treatments for psychopathy were developed, the practical problem of how to respond to excused psychopaths would be vastly reduced.

Preventive Civil Confinement of Addicts

The Supreme Court has approved a special form of criminal justice-related civil commitment for so-called mentally abnormal sexually violent predators. The criteria for such commitments are, 1)a criminal charge or conviction; 2)a mental abnormality; 3)predicted dangerousness; and, 4)“serious” difficulty controlling oneself [8]. This type of commitment is different from traditional involuntary civil commitment because it requires at least a charge of criminal behavior, whereas traditional commitment may be triggered simply by a threat of dangerous behavior. The Supreme Court upheld such commitments even when they are imposed after the completion of a prison term for precisely the same type of behavior that now justifies involuntary commitment. Although the standard for responsibility in the criminal justice and involuntary commitment systems need not be the same, these forms of commitment have received withering criticism because the rationality sufficient for criminal blame and punishment should be sufficient to avoid involuntary civil commitment. Nonetheless, this type of commitment is constitutional and its potential application to psychopaths should be considered.

Although psychopathy is not considered a legally sufficient abnormality to support traditional involuntary commitment, it would be sufficient to support this type of commitment if the psychopath were dangerous and had “serious” difficulty controlling himself. The Supreme Court has made it clear that the state is not bound in its legal criteria by psychiatric or psychological definitions of mental disorder. It may define mental abnormality in any way that is minimally rational. Moreover, psychopathy is a recognized abnormality despite its present exclusion from DSM-IV-TR. Further, psychopathy is a prominent risk factor for future violent behavior and would be a rationally-included variable in a violence prediction assessment. The only difficulty would be whether psychopaths are sufficiently non-responsible to qualify for civil confinement on a “disease” theory within desert-disease jurisprudence.

The previous section of this paper argued that severe psychopaths should be excused from criminal responsibility on cognitive or cognitive-affective grounds. This would satisfy the disease justification for civil confinement and would distinguish psychopaths from sexual predators who are considered criminally responsible. But the Supreme Court imposed a disease-based non-responsibility requirement of serious difficulty controlling one’s behavior, which does not appear to be a cognitive or cognitive-affective criterion. A jurisdiction almost certainly could constitutionally adopt a cognitive-affective test for this type of commitment rather than a control test, but the Court’s holding in Crane concerning control requires attention.

As suggested above, control tests are notoriously difficult to conceptualize and measuring control difficulties independently is well nigh impossible. I also suggested, however, that control tests can ultimately be assimilated to cognitive tests because the reason people have difficulty controlling themselves is that they cannot bring good reason to bear to guide their behavior. In the cases of people with impulse control disorders, paraphilias (disorders marked by abnormal sexual desires that cause distress) and the like, there is no general rationality impairment. Instead, they have difficulty accessing good reason when they are in the throes of peak desire or craving. In contrast, psychopaths have no such allegedly “overwhelming” desires, but when they want to violate the rights of others, they lack the capacity to access the best reasons–conscience and empathy–not to do so. Consequently, they are unable to control their behavior because they cannot guide it by reason. In sum, the control criterion would not exclude psychopaths from this form of commitment.

This type of special commitment would avoid some of the most unsettling problems associated with general involuntary civil commitment. Widespread traditional involuntary commitment of psychopaths might raise various civil liberties problems. Although psychopathy is a strong risk factor for violence, serious violent conduct is still an infrequent event in this population and there would be substantial numbers of unnecessary commitments based on false positive predictions. The best predictor of future behavior is past behavior, however, and tying quasi-criminal commitment to a charge or conviction for serious crime would reduce the risk of false positives.

I conclude that this form of commitment would be justified for severe psychopaths and would provide an alternative to criminal justice resolution.

Science, Psychopathy and Law

Scientific advances in neuroscience, psychology and other disciplines might well change the justifiable legal response to psychopaths because they may alter our view of psychopaths’ capacities and may contribute to greater predictability of future behavior.

Before considering these possibilities, however, first note a methodological point. Psychopathy is defined behaviorally by cognitive and emotional impairments and persistent antisocial conduct. Anything further we learn about the genetics, neurobiology, or psychology of psychopaths depends on our ability already to identify psychopaths reliably. If we cannot be sure that the subject population of a study is psychopaths, we cannot know if genetic, neurobiological or psychological discoveries are really about psychopathy. Now, it is of course true that various discoveries may cause us to rethink the behavioral diagnostic criteria. For example, if behaviorally similar psychopaths have vastly dissimilar neurobiology or genetics, it may cast doubt on whether there is a unitary disorder rather than discrete disorders with a similar presentation. This would be especially true if there were prognostic or treatment differences between the two groups. But making any progress does depend at the outset on studying a reliably identified population.

Whatever scientific investigation may disclose, for the purposes of the law, the agent’s behavior will be the touchstone of responsibility because all responsibility criteria are behavioral.

If the defendant is behaviorally rational, the defendant will be considered responsible, no matter what his brain scan may indicate. And vice versa. Actions speak louder than images. It is possible, however, that future discoveries may persuade lawmakers that psychopaths should continue to be held responsible or the opposite, depending on what we learn. For example, if the broad view of psychopathic irrationality were supported by further study, a case for excuse would be strengthened. Further, if psychopathy were deemed to be a legally-sufficient basis for an insanity defense, then new scientific techniques might help us more accurately diagnose psychopathy, especially in cases in which the behavioral evidence is not entirely clear.

New techniques may also help us predict future dangerous behavior far more accurately than we do today. If some psychopaths were excused or if they were subject to involuntary civil confinement, this would represent a major advance in both fairness to the psychopath and in the ability to protect society from them in appropriate cases.

Finally, as mentioned above, if successful treatments for psychopathy were discovered, this might solve many of the civil libertarian concerns that wide-scale involuntary commitment would pose.

Conclusion

At present, the law holds psychopaths criminally responsible and does not involuntarily hospitalize them if their only abnormality is psychopathy. This paper argues, however, that severe psychopathy should be a basis for non-responsibility in appropriate cases because psychopathy deprives people of rational capacities that are fundamental for fair ascriptions of blame and punishment.

Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.University of Pennsylvania Law SchoolPhiladelphiaUSA

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