Ethical Issues with the Insanity Defense in Criminal Law
This paper examines the ethical dimensions of the insanity defense in criminal law, analyzing the competing interests of defendants, victims, legal professionals, and mental health clinicians. Drawing on case law, scholarly literature, and psychological research, the paper traces the historical origins of the insanity defense from the M'Naughten case through contemporary applications, explores debates over temporary insanity and borderline personality disorder, considers the role of neuroscience in objective assessment, and addresses special circumstances such as medication noncompliance, wartime conduct, and brainwashing defenses. The paper concludes with recommendations for refining ethical and legal standards to better distinguish genuine mental illness from calculated use of the defense.
- Introduction: Core ethical tensions in the insanity defense
- Background and Origins of the Insanity Defense: M'Naughten case and foundational legal principles
- Key Legal and Ethical Debates: Temporary insanity, BPD, competency, and jurisdictional issues
- Special Circumstances and Complex Cases: Release decisions, brainwashing, PTSD, and wartime conduct
- The Role of Neuroscience and Medical Ethics: Objective brain-scan evidence versus psychiatric opinion
- Conclusions and Recommendations: Reform proposals and professional accountability standards
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What makes this paper effective
- The paper synthesizes a broad range of peer-reviewed sources across law, psychiatry, psychology, and neuroscience to build a multi-faceted argument rather than relying on a single disciplinary lens.
- Concrete case examples — M'Naughten, John Hinckley, Patty Hearst, Lorena Bobbitt, and the Aurora shooter — ground abstract ethical arguments in recognizable real-world events.
- The paper consistently acknowledges competing interests (defendants' rights vs. victims' justice) without collapsing into a one-sided polemic, which strengthens its analytical credibility.
Key academic technique demonstrated
The paper demonstrates effective use of synthesized literature review to map an ongoing legal and ethical debate. Rather than summarizing sources one by one, the author weaves together findings from legal journals, psychiatry research, and neuroscience studies to show where consensus exists and where genuine ambiguity remains — a technique central to graduate-level analytical writing on contested policy questions.
Structure breakdown
The paper opens with a problem statement establishing the core ethical tension. It then moves through historical background, contested legal standards (including temporary insanity and BPD), special-circumstance scenarios (war, medication noncompliance, brainwashing), and the promise of neuroscientific evidence. It closes with a recommendations section that calls for clearer professional standards and accountability for legal personnel who exploit the defense. Each section builds logically on the prior one.
Introduction
The insanity defense may seem to have a clear and legitimate place in the legal world. However, defining who is insane, who is not insane, what the definition of insanity is, whether insanity is temporary or permanent, who should be held liable and under what circumstances — all of these are pressing questions that are extremely difficult to answer in a scientific, dispassionate, and objective fashion. This difficulty arises from the competing rights and burdens of everyone involved: defendants, victims, legal counsel, and clinicians. This paper seeks to examine questions about the ethics of the lawyers, defendants, prosecutors, and clinicians involved in the insanity defense process.
There are numerous cases, both current and historical, regarding the insanity defense. In some cases, those convicted of committing heinous crimes were found not guilty by reason of insanity (NGRI). In some instances, the person who committed the crime was not aware or cognizant of his or her actions at the time the crime was committed. In other cases, the perpetrator was not in his or her right mind and was afflicted by some form of mental illness. Even given the fairly basic rationale for the plea, several ethical issues become apparent in its application. The criminal justice system is sworn to protect and serve the community. In many cases, ethical questions arise only when there is a misuse of the insanity defense. This defense can sometimes cause one to question whether the system is working as intended, particularly because victims of a perpetrator are left to process the loss of their loved ones in the wake of a not guilty by reason of insanity verdict. In some situations, criminals are not competent to stand trial, leaving victims' families without closure — especially when no death or life sentence is involved. However, criminals who commit crimes without knowledge of their acts should be entitled to receive proper help and a fair trial, rather than simply being imprisoned and left untreated (Cornell, 2015).
Background and Origins of the Insanity Defense
The insanity defense is based on the assumption that at the time of the crime, the defendant was not sound of mind and was therefore incapable of appreciating the nature of the crime or differentiating right from wrong. For those who are deemed insane, treatment rather than imprisonment is the proper protocol (Cornell, 2015).
The insanity defense holds that a criminal should not be found guilty on the basis of mental illness — that is, not guilty by reason of insanity — because he or she could not distinguish between right and wrong, or between good and evil. The insanity defense traces its origins to Daniel M'Naghten, an Englishman who shot and killed the secretary of British Prime Minister Robert Peel in 1843. M'Naghten was subsequently sentenced to a mental institution for the remainder of his life because he was declared mentally ill at the time he committed the crime (Legal Information Institute, 2010; Cornell, 2010).
Some people use "temporary insanity" or "heat of the moment" defenses to justify why a crime occurred while simultaneously arguing that the person who committed the offense should not be incarcerated (Covey, 2011). Much of the medical, psychology, and psychiatry fields strive to be precise and specific, but there is considerable room for interpretation and manipulation when it comes to mental health details surrounding crimes and associated defenses — except where objective tools such as brain scans are employed (Shiels, 2014).
Key Legal and Ethical Debates
The criminal justice system is supposed to protect the lives of its citizens, though this is not always the outcome. Although the laws of the land are designed to protect, the judicial system does not always appear to adhere to that principle because some laws exist for those who are guilty yet have ostensibly justified reasons for their crimes. Many cases and controversies are associated with crimes committed by those pleading not guilty by reason of insanity, even if the final outcome consists of psychiatric confinement. Criminal commitment is a legal procedure by which a person found not guilty of a crime by reason of insanity is confined to a psychiatric hospital. Notably, even persons with mental illnesses have a right to be treated fairly despite the crimes they have committed. Nonetheless, the insanity defense has a long history with both pros and cons, and its effectiveness — as well as the positive and negative impacts it has on those who invoke it — continues to be debated. It is therefore vital to understand when the insanity defense should appropriately be utilized (Cornell, 2015).
The central issue is balancing the right of defendants — even those who are grossly mentally ill — not to be simply imprisoned without treatment, against the right of victims to see clearly lucid criminals face appropriate consequences rather than invoking a legal defense that does not genuinely apply to their actions. There is a rich body of scholarly and legal literature that informs how to strike that balance properly. One treatise on the subject argues that professionals need to use a three-stage process to locate a defendant on the appropriate point of the legal responsibility/mental health spectrum. The authors note that if the three-stage process is not initiated properly, this can directly undermine subsequent choices and assessments as the process continues (Kalis & Meynen, 2014).
One method of clearly distinguishing between truly insane acts and defendants who are "playing insane" is the use of forensic psychiatry. While forensic psychology is fairly well known, forensic psychiatry is less prominent but has become equally important, particularly when defendants are using or likely to use the insanity defense (Meynen, 2012). While some argue that over-analyzing mental dysfunctions can lead to incorrect decisions, there are disorders where the question is extraordinarily complex and requires a psychiatrist to assess it exhaustively. One such disorder is borderline personality disorder (BPD). One study describes BPD as a "complex mental disorder that straddles the line between psychosis and neurosis" (Sisti & Caplan, 2012). That same study holds that even though BPD is a debilitating and serious disorder, the disorder alone does not "by itself provide sufficient grounds for voiding responsibility for criminal acts" (Sisti & Caplan, 2012). This is analogous to being intoxicated and killing someone in an accident: while the intent may not be present, there was enough lucidity and forethought involved that the acts cannot be legally excused by that factor alone. Rather than a black-and-white framework for evaluating extensive mental illnesses like BPD, many scholars propose a sliding scale to identify when someone should be held culpable and when they should not. However, such a "gray area" is certain to frustrate those on both ends of the spectrum — victims seeking justice and defendants seeking relief from criminal liability. A definitive system would be preferable, but is simply not possible given the complexities involved, including the calculated actions of defendants and their counsel (Sisti & Caplan, 2012).
The propensity of defendants to do whatever it takes to avoid conviction is not, however, always the pattern observed. Whether because they genuinely are insane or because they wish to challenge the system, some defendants who probably should claim insanity choose not to, raising the question of whether such a person is even competent to stand trial. Such a situation arose in New York roughly two decades ago, when a criminal defendant refused counsel's advice to claim an insanity defense. The question became whether the defendant was sufficiently lucid to aid in his own defense and whether he should stand trial given competency concerns. Among those surveyed on the matter, opinions were nearly evenly split between those who believed he should immediately stand trial and those who believed he should not stand trial in his current state. Notably, most mental health professionals agreed that he was competent, while prosecutors tended to disagree. Regardless, it was found that New York law at that time was far from clear regarding how such situations could or should be handled (Cheatham & Litwack, 2003).
Some have reacted to the perceived overuse and misuse of the insanity defense by seeking to restrict when it can be invoked — a move that, while potentially harmful to defendants who genuinely need it, is driven by understandable concerns. Many politicians and media commentators have publicly contemplated whether restricting the insanity plea is appropriate to prevent its misuse. However, the data that would support or contradict such a restriction is simply not sufficient, in the view of many legal and political scholars. What should be avoided, one treatise argues, is excessive deference to the "whims of what may be called 'public opinion.'" This article, which references the New York test case, also examines the actions of M'Naghten and would-be Reagan assassin John Hinckley when arguing that the insanity defense and its definition are frequently misunderstood and misapplied (Blau, McGinley, & Pasewark, 1993).
Jurisdictional complications also arise when it comes to the insanity defense. In areas such as Australia, forensic mental health orders — whether related to an insanity defense or other proceedings — raise pertinent questions about patient movement, defendants' rights during trial and sentencing, and related concerns (Carroll et al., 2009). Some scholars take things further still and question how insanity defenses came to be at all. The historical starting point for this line of analysis is the 1867 murder case of Alexander Dingwall in the United Kingdom. At that time, insanity defense murder cases were referred to by Lord Deas as "murder with extenuating circumstances." Around the same period, the last public execution in Scotland took place in 1868. Consistent with earlier examples, the analysis holds that intoxication alone — as a means of losing one's reason and self-control — is insufficient to prevent criminal liability, though matters grow considerably murkier beyond that point. "Alienation of reason" was identified as the primary metric, regardless of the cause of such alienation. The question of alcohol consumption is directly relevant in the Dingwall case, as he was apparently severely intoxicated when he murdered his wife. One question during trial was whether Dingwall was "quite right otherwise," beyond his propensity to drink. As testimony unfolded, it appeared that while alcohol certainly affected Dingwall's mindset and actions, he did not seem to technically qualify as mentally ill. However, an advocate for the accused argued that several of Dingwall's close relatives had been committed to an asylum, and that this hereditary history should be considered relevant. While the precise outcome involved considerable legal debate, the general principle that emerged was that although alcoholics cannot use their vice as a defense, those who are truly mentally ill through no fault or choice of their own can invoke the insanity defense — provided their inability to act logically and normally is impaired beyond a certain threshold (Shiels, 2014).
References
Blau, G. L., McGinley, H., & Pasewark, R. (1993). Understanding the use of the insanity defense. Journal of Clinical Psychology, 49(3), 435–440.
Carroll, A., Scott, R., Green, B., Dalton, T., Brett, A., & McVie, N. (2009). Forensic mental health orders: Orders without borders. Australasian Psychiatry: Bulletin of the Royal Australian and New Zealand College of Psychiatrists, 17(1), 34–37. doi:10.1080/10398560802311193
Cheatham, C. S., & Litwack, T. R. (2003). Professionals' attitudes regarding whether a New York defendant who delusionally refuses a viable, counsel-recommended insanity defense should be found competent or incompetent to stand trial. Journal of Psychiatry & Law, 31(4), 433–460.
Cornell. (2015, February 10). Insanity defense. Retrieved February 10, 2015, from http://www.law.cornell.edu/wex/insanity_defense
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