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Criminal Justice Issues


Society has long recognized the need to distinguish between those defendants charged with a crime who are responsible for their acts and those who are not. The insanity defense exists to make that distinction for people with a mental disability. This defense is currently codified by the American Law Institute (“ALI”) in the Model Penal Code (“MPC”) as the defense of “Mental Disease or Defect Excluding Responsibility,” which MHA supports. But this position statement will use the more traditional name: insanity. By whatever name, the principles behind the insanity defense are clear:

  • Criminal sanctions promote public safety through the deterrent effect of the punishment itself and the stigma of a criminal conviction.
  • Criminal sanctions also punish people who harm others.
  • However, without blameworthiness, deterrence is not effective and punishment is not justified.1 2

When an individual is determined to be not criminally responsible, acquittal through a verdict of “not guilty by reason of insanity” (NGRI) is the appropriate action. Concerns about public safety and the need for treatment usually remain after such an acquittal, but these concerns should be addressed through civil commitment -- involuntary treatment in mental hospitals until the danger has passed -- rather than through confinement in prison. Therefore, the Mental Health America (MHA)’s position is as follows:

  • It is vital that states provide for the ongoing availability of a broadly-defined insanity defense resulting in a verdict of not guilty by reason of insanity (NGRI).
  • MHA supports the ALI-MPC formulation of the insanity defense.
  • When the insanity defense does not apply, the ongoing availability of the mens rea (lack of criminal intent) and diminished capacity defenses remains critically important. The ALI-MPC assures that these defenses remain intact.
  • “Guilty but mentally ill” laws should be abolished as they are unjust, ineffective, and misleading.
  • States should provide individuals who are acquitted by reason of insanity with appropriate, recovery-oriented treatment, preparing them for life after civil commitment.
  • The decision whether to plead the insanity defense must be entirely the defendant’s, but courts must ensure that the defendant is capable of understanding the consequences of the decision, and that juries understand the implications of an NGRI acquittal.
  • Because appreciation of mental health conditions and their effect on decision-making goes to the essence of criminal intent, people with mental illness should have access to specialized courts with mental health expertise and a comprehensive understanding of treatment alternatives in dealing with both criminal and civil justice issues.


Depending on the jurisdiction, courts use one or a combination of the following tests for legal insanity:

  • The "M'Naghten Rule" - Defendant either did not understand what he or she did, or failed to distinguish right from wrong, because of a "disease of mind." This legal test for the insanity defense is purely “cognitive” and was established by British common law in the mid-19th Century. The M'Naghten rule was embraced with almost no modification by American courts and legislatures for more than 100 years, until the mid-20th century. It is used in a majority of U.S. states and other jurisdictions around the world today.
  • The "Irresistible Impulse" Test - As a result of a mental disease, defendant was unable to control his impulses, which led to a criminal act. This is a purely “volitional” test. The “Irresistible Impulse” test is used by a number of states in combination with the M’Naghten rule. Essentially, the test allows for a defendant to be found not guilty by reason of insanity if his or her mental illness was such that, although recognizing the wrongness of the offense, he or she was compelled to commit the offense anyway.
  • The "Durham Rule" - Regardless of clinical diagnosis, the defendant's "mental defect" resulted in a criminal act. In the Durham case, the D.C. Circuit ruled that a defendant is entitled to acquittal if the crime was the product of his mental illness (i.e., the crime would not have been committed but for the disease).3 The test is broader than either the M'Naghten test or the irresistible impulse test. The test has more lenient guidelines for the insanity defense, and it also addressed the issue of convicting mentally ill defendants, which was allowed under the M'Naghten Rule. However, the Durham standard drew much criticism because of its expansive definition of legal insanity.
  • The Model Penal Code (ALI-MPC) Test - Because of a diagnosed mental defect, defendant EITHER failed to understand the criminality of his acts, OR was unable to act within the confines of the law. The MPC thus allows both lack of understanding and lack of control as a basis for pleading the insanity defense. The MPC ALSO codifies a mens rea defense and establishes a limited diminished capacity defense for cases when the insanity defense does not apply, as explained below.

A few states don't allow the insanity defense against criminal charges, including Idaho, Kansas, Montana, and Utah. Three of these states, with the exception of Kansas, allow "guilty but insane" verdicts, which often provide for institutionalization in lieu of prison. Most states that recognize legal insanity use either the M'Naghten Rule (sometimes in combination with the irresistible impulse test) or the ALI-MPC. Only New Hampshire uses the Durham standard. MHA favors the ALI-MPC version of the insanity defense.

Necessary Components of a Comprehensive Insanity Defense

Standard for Insanity

In order to effectively distinguish between those who are and those who are not criminally responsible for their acts, the insanity defense must contain both a “cognitive” prong and a “volitional” prong.4 That is, an insanity defense should exculpate both those who are unable to understand that their act is wrong, as well as those who are unable, due to mental disability, to control their actions.

Section 4.01 of the ALI-MPC,5 provides a comprehensive insanity defense. Section 4.01 of the MPC remains substantially unchanged from when it was initially drafted in 1962 and currently provides as follows:

Section 4.01: Mental Disease or Defect Excluding Responsibility.

(1) A person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect he [or she] lacks substantial capacity either to appreciate the criminality/wrongfulness of his [or her] conduct or to conform his [or her] conduct to the requirements of the law.

(2) As used in this Article, the terms “mental disease or defect” do not include an abnormality manifested only by repeated criminal or otherwise anti-social conduct.

This formulation represents the consensus of American legal scholars on the appropriate scope of the insanity defense. § 4.01(1) establishes both “cognitive” and “volitional” prongs, ensuring that the defense is appropriately inclusive, but § 4.01(2) minimizes the risk that the defense will be over inclusive or actually encourage repeated criminal activity.6  Specifically, it requires a clinical basis for insanity that is independent of the criminal act and requires that that the lack of appreciation of wrongfulness of the act the criminal act be caused by a mental disease or defect not just the result of ignorance.  

Mental Health America (MHA) endorses the MPC formulation of the insanity defense and rejects the narrow formulation of the insanity defense adopted by Arizona and upheld by the United States Supreme Court in Clark v. Arizona.7 It is noteworthy that the fundamental gravamen of the Clark case was federalism. The Clark Court, after reviewing the various formulations of the insanity defense adopted by the state, held that precise nature of the insanity defense “is substantially open to state choice.” (emphasis supplied)    But a fair reading of Clark suggests that the Court believed that states must provide some form of an insanity defense. The Clark Court relied on the fact that Arizona provided defendants with the defense of insanity in its second holding. That holding permitted Arizona to restrict the use of psychiatric evidence regarding the defendant’s mens rea because such evidence was admissible to establish insanity.   

Burden of Proof

The ALI-MPC and the vast majority of states place the burden of proving insanity on the defendant. The standard of proof varies from jurisdiction to jurisdiction.8 The defense should have the burden of introducing evidence of cognitive or volitional non-responsibility. In accordance with the ALI-MPC insanity defense, the prosecution should then, in addition to proving beyond a reasonable doubt that an individual committed the crime in question, also have the burden of proving by a preponderance of the evidence that the defendant was not insane.9

An Informed Decision to Plead Insanity

All defendants must be informed of the consequences of any plea. A defendant contesting a case is ordinarily is informed through his or her attorney. But since 1969 in Boykin v. Alabama,10 when a criminal defendant pleads guilty, the accused must be addressed personally and in open court. “Intentional relinquishment or abandonment of a known right or privilege. . . cannot be presumed from a silent record.”11 MHA submits that the same factors which require the court to establish in open court that a guilty plea is voluntary and intelligent should apply to a plea of not guilty by reason of insanity, for the following reasons:

While, unlike a guilty plea, a finding of NGRI is not a conviction and should not result in punishment, it often has substantial long-term consequences.  People found not guilty by reason of insanity will often be confined longer than they would have been had they been found guilty.12  The conditions of their confinement will also be quite restrictive. It is not clear that most persons with serious mental illnesses will be safer and receive better care in a mental hospital than in a prison, where they probably will be segregated from the general prison environment. The treatment and confinement environment is what counts, not the label. Thus, respect for individual autonomy requires that the court have a dialogue with the defendant to establish that an NGRI plea represents an informed and free choice between difficult-to-predict confinement and treatment options. 

The likely length of confinement after an NGRI verdict, the likely treatment to be received, and the likely conditions of confinement are critical factors in deciding whether or not to invoke the insanity defense. Just as courts must ensure that defendants are competent to plead guilty and are aware of the consequences, so too should courts ensure that defendants are competent to plead NGRI and are informed about the likely consequences of the plea.13

Notice to Jury

MHA recommends that juries be instructed on the consequences of a finding of not guilty by reason of insanity. Currently, most jurisdictions to not mandate that juries be instructed about the effects of an insanity acquittal. The ABA Criminal Justice Mental Health Standards14 recommend that juries be fully instructed in order to level the playing field between different verdicts. Most people are aware of the broad consequences of a criminal guilty verdict and a not guilty verdict. But the consequences of an insanity acquittal are varied and complicated. The average person is not aware of the effects of an NGRI acquittal, and therefore may make a decision based on community safety without being aware that most NGRI acquittees are usually hospitalized. While juries do not need to know the specifics of the hospitalization, knowing that acquittees will not be released until they are no longer a danger to themselves or others can help juries make the best decision based on the facts.

The Consequences of Pleading Insanity

Insanity acquittees are subject to a variety of consequences. Among these are automatic commitment of insanity acquittees and release proceedings which differ from civil commitment.

An individual who is acquitted on the basis of insanity should be treated. However, it is critically important, both out of concern for promoting the public safety and out of concern for the defendant’s rights, that the purpose of this treatment is rehabilitation and recovery, not to serve as a punitive alternative to imprisonment. That is, the aim of the treatment should be to eventually release an individual into the community, not to punish that individual for a crime for which the defendant has been judged not morally culpable.

In U.S. v. Jones, 565 U.S. 400 (2012),15 the Supreme Court found it unconstitutional for states to confine insanity acquittees in a mental health facility for periods longer than they would have been imprisoned had they been found guilty of the crime.16 But this still routinely occurs.17  Setting special release conditions and retaining criminal justice supervision are violations of the fundamental premise of the insanity defense, which is that confinement after an NGRI acquittal is appropriate only for as long as the additional period of confinement is clinically justified and serves a valuable rehabilitative purpose, in accordance with civil commitment laws, outside the criminal justice system. MHA advocates that insanity acquittees be released as soon as a professional assessment shows they have no serious mental illness that makes them dangerous to themselves or others.  NGRI acquittees cannot be presumed to be dangerous or subject to ongoing mental illness under Foucha v. Louisiana (1992)18 and must be released after they are no longer mentally ill AND dangerous to self or others.

Extended treatment periods may very well further legitimate goals, but the policy of long-term treatment after NGRI verdicts without a finding of ongoing mental illness causing danger to self or others increases the risk of treatment being used as a pretext for punishment. In order to protect against this, states should adopt rigorous release standards and procedures. Review boards that are as independent of the criminal justice system are one mechanism to achieve this goal. These boards serve to monitor an insanity acquittee’s clinical progress and evaluate the need for continued treatment. The modern trend in states with a full insanity defense is toward use of such a civil system.19  Independent review boards serve to place the treatment and release decision-making process in the hands of those most qualified to make such determinations, and those who are most likely to act out of public safety and treatment concerns rather than in response to official and political pressure.

Some states opt instead for a criminal justice model, placing procedural barriers to release after an NGRI verdict. MHA opposes these laws and recommends instead that an NGRI acquittee’s ongoing treatment and confinement be adjudicated in the civil rather than the criminal justice system. This is important for three reasons. First, (with the possible exception of mental health courts) because the criminal court is not adequately equipped to handle these psychiatric testimony and treatment alternatives in the way that a civil court is. Second, because once a finding of NGRI is made, acquittees are by definition acquitted and should no longer be involved with the criminal justice system, with all of its biases. Finally, third, by reinforcing the line between an NGRI acquittee and a person subject to civil commitment, it is less likely that NGRI acquittees will be treated punitively, rather than rehabilitated and guided to a recovery path.

NGRI acquittees are no more dangerous than civil committees, yet, according to a 2017 survey conducted by the New York Times, they are held for on average 73 times as long as a person subject to civil commitment for the same mental illness. The Times also reported that – in a contrary trend -- some states, like Tennessee, have opted not to automatically civilly commit insanity acquitees. Tennessee requires post-acquittal evaluation of dangerousness on an outpatient basis. Now, only 55 percent of Tennessee’s NGRIs are committed after acquittal, without any difference in recidivism.20

The Insanity Defense in Practice

Despite public fears, defendants do not abuse the insanity defense. In felony cases, the defense is invoked less than 1% of the time, and even when it is employed, it is only successful 25% of the time. Further, in approximately 70% of the cases in which the defense has been successfully employed, the prosecution and defense have agreed on the appropriateness of the insanity plea before the trial.21  Thus, a contested NGRI plea is a long shot. Finally, even after Foucha, there is a high likelihood of court-mandated confinement and involuntary treatment following an insanity acquittal, often lasting a substantial length of time, which serves protect the public from defendants who may be dangerous and also to discourage people from inappropriately using the defense.22  These realities all refute public suspicion that the insanity defense creates a loophole to avoid deserved criminal liability, especially in notorious death penalty cases, like the attempted assassination of President Reagan (where an NGRI defense prevailed) or the subsequent Aurora, CO theater shooting (where it did not).

The insanity defense is under-utilized due to the general failure to fully fund criminal defense lawyers for persons who are indigent.  Over-worked and under-paid public defenders may not have the time, or sometimes the training, which would lead them to fully investigate whether an insanity defense is warranted and may lack the resources to retain a mental health expert whose opinion is essential to support the defense.

Although the wariness with which the public often views the insanity defense is unmerited, some states’ insanity laws nonetheless reflect this suspicion. After the MPC was first promulgated, most states initially incorporated identical or substantially similar defenses into their laws. Since the late 1970s, however, many states have taken action to limit their insanity defense laws and to bring them back toward pre-MPC formulations.23 As of 2004, only 20 states still had insanity defense laws that incorporated the MPC formulation in its entirety or in a substantially similar fashion.24

The two-pronged protection of § 4.01 is necessary in order to comply with two different constitutional requirements: due process and the prohibition against cruel and unusual punishment.25 In considering these issues, however, the Supreme Court has left considerable discretion to state courts. The Court has indicated that states may be required to provide at least some minimal defense based on mental illness, but has not yet found a state’s law to be below that minimum and has declined to specify exactly what that minimum entails. The Court upheld Arizona’s limited insanity defense in Clark v. Arizona,26 and denied certiorari in Delling v. Idaho,27 a case alleging that Idaho’s replacement of the insanity defense with a “guilty but mentally ill” verdict constitutes a due process violation. Still, three justices dissented from the Court’s denial of certiorari in Delling, arguing that Idaho’s practice does violate the constitution. MHA agrees with this dissenting position. 

MHA strongly opposes the popular, scientifically-unfounded belief that mental illness predisposes a person to act violently. See MHA Position Statement 72, Violence: Community Mental Health Response,28 Thus, restricting the insanity defense would not enhance public safety.

Alternatives to the Insanity Defense

The Mens Rea and Diminished Capacity Defenses

To be guilty of a crime, a person must intend to do the act that the state seeks to punish. This “mens rea” – criminal intent, translated as “guilty mind” --  is a constitutional requirement, although courts have allowed states to limit it in certain ways. Thus far, the Supreme Court has held that a diminished capacity defense is not constitutionally guaranteed. But Mental Health America believes that people accused of crimes should be able to assert both mens rea and diminished capacity defenses at trial using expert psychological evidence. This is the position endorsed by the MPC.

Defining the Defenses

In anything more than trivial offenses, a finding of guilt in a criminal trial generally requires some form of mens rea, or “guilty mind,” often expressed as knowledge or intent.29 A defendant that does not have the required mens rea is not guilty of the crime.30 This is the mens rea defense.

A diminished capacity defense is different from a mens rea defense, but the two overlap considerably and there is not always a clear distinction between the two. A diminished capacity defense allows for mitigation of a criminal conviction based on the defendant’s mental impairment, even if the insanity and mens rea defenses have both failed.31  The diminished capacity defense reflects the notion that a defendant, while guilty, may, nevertheless, be guilty of a less serious crime due to mental impairment.

A crime’s required mens rea is a critical element of the offense, and without it a defendant cannot be found guilty. However, some courts have upheld state laws that interfere with this requirement. The Supreme Court in Clark upheld Arizona’s rule that effectively precludes the use of most psychological evidence in making a mens rea or diminished capacity defense at trial, and instead relegated it to use only in pleading insanity.32  In so holding, the Court simultaneously limited the defendant’s ability to establish a mens rea defense and declared that neither the mens rea nor the diminished capacity defenses are constitutionally required. As of 2007, only three states still allowed a diminished capacity defense.33

As the dissent in that case noted, the practical effect of this rule is that “a person would be guilty of first-degree murder if he knowingly or intentionally …committed the killing under circumstances that would show knowledge or intent but for the defendant’s mental illness.”34 MHA joins the dissent in arguing that such a rule is unconstitutional because it results in a guilty verdict even when the defendant did not satisfy a critical element of the crime. Moreover, even if the defendant possessed the required mens rea, the mental illness may remain relevant to determining the extent of his or her blameworthiness, thus necessitating recognition of a diminished capacity defense as well.

The ALI-MPC Approach

The MPC both assures a mens rea defense and establishes a limited diminished capacity defense in the same section, which provides as follows:

Section 4.02: Evidence of Mental Disease or Defect Admissible When Relevant to Element of the Offense; Mental Disease or Defect Impairing Capacity as Ground for Mitigation of Punishment in Capital Cases.

(1) Evidence that the defendant suffered from a mental disease or defect is admissible whenever it is relevant to prove that the defendant did or did not have a state of mind that is an element of the defense.

(2) Whenever the jury or the Court is authorized to determine or to recommend whether or not the defendant shall be sentenced to death or imprisonment upon conviction, evidence that the capacity of the defendant to appreciate the criminality [wrongfulness] of his [or her] conduct or to conform his [or her] conduct to the requirements of law was impaired as a result of mental disease or defect is admissible in favor of a sentence of imprisonment.

Viewed in light of ALI-MPC § 4.01, § 4.02 indicates that mens rea and diminished capacity defenses are to be available independently of the insanity defense. § 4.02(2) provides a diminished capacity defense only in capital cases. While this formulation is more protective than the current law in the vast majority of states, the diminished capacity defense should not be limited to capital cases. A broader, but still sufficiently limited, defense would allow diminished capacity mitigation in all specific intent crimes, not only in capital crimes.

Guilty but Mentally Ill Laws and Lack of Constitutional Requirement for the Insanity Defense

A few states do not allow the insanity defense against criminal charges, including Idaho, Kansas, Montana, and Utah.  In 2020, the United States Supreme Court rejected a challenge to Kansas’ decision to abolish the insanity defense. 35  The Court found that the states were free to formulate any version of the insanity defense they thought appropriate or none at all.  In doing so the Court emphasized that, under Kansas law, a defendant was (a) entitled to introduce evidence of mental illness to establish that she or he lacked the mental state required to be convicted of the crime and, therefore, to be acquitted; and (b) entitled to introduce evidence of a mental illness in sentencing which could result in a commitment to a mental health facility rather than a prison.  

Idaho, Montana and Utah allow "guilty but insane" verdicts, which provide for institutionalization in lieu of prison, and, as noted above, Kansas law also permits, but does not require, this result.  Most states that recognize legal insanity use either the M'Naghten Rule (sometimes in combination with the irresistible impulse test) or the ALI-MPC. Only New Hampshire uses the Durham standard. MHA favors the ALI-MPC version of the insanity defense.

Laws establishing a “guilty but mentally ill” (GBMI) verdict are inappropriate for two reasons. First, they are inappropriate because the GBMI verdict is no different in practice from a finding of guilty. Second, they are inappropriate because this alternative to the insanity defense may confuse jurors. These fundamental problems persist whether the GBMI verdict is provided in addition to, or as a replacement for, the NGRI verdict.

A GBMI verdict provides no benefit to society or to criminal defendants because it has the same consequences as a guilty verdict.  Someone found GBMI may be given any sentence that she or he could have been given if found guilty.  That includes a sentence of death.36  Virtually every person found GBMI is sent to prison.   Persons found GBMI are entitled to mental health services while imprisoned.  However, they have no greater right to mental health services in prison than those simply found guilty, since all persons confined in prison have a constitutional right to mental health services.37  While GBMI statutes typical permit defendants to be transferred to mental hospitals, these provisions are permissive rather than mandatory and are rarely utilized.38

Because the GBMI verdict is indistinguishable from the guilty verdict, GBMI laws serve no purpose other than to confuse jurors. Jurors may understandably believe that the GBMI verdict is a compromise between the NGRI and guilty verdicts, and thus the availability of a GBMI verdict may cause them to find a defendant GBMI when they would not have been willing to give a guilty verdict. This issue is compounded by the fact that jurors are often wary of the NGRI verdict.39  Although empirical evidence from actual trials is not yet available, researchers have considered, in the mock trial setting, the impact on jury preferences of the simultaneous availability of NGRI and GBMI verdicts. Research indicates that juries may use GBMI as a mechanism for “avoiding the difficult moral and social issues raised by an insanity defense.”40

Defendants’ challenges of the GBMI verdict as a due process violation have yet to succeed.41  As of 2009, over 20 states provided for a GBMI verdict.42  Four of these states had eliminated the NGRI verdict entirely and replaced it with GBMI. The remaining 16 states with GBMI laws allow for both an NGRI verdict and a GBMI verdict.  In either context, the GBMI verdict is inappropriate and seriously undermines the important policies that require maintaining the insanity, mens rea, and diminished capacity defenses, discussed above.

Call to Action

MHA encourages policy and legal changes as necessary in order to achieve the following goals:

  • States should provide a full insanity defense. When defendants’ mental illnesses prevent them from understanding the wrongfulness of the act or prevent them from controlling their behavior, they should be acquitted by reason of insanity. Criminal liability in these instances is unfair. Inappropriate, and ineffective.
  • Even if a defendant does not qualify for an insanity acquittal, the mental illness may remain critically relevant to the criminal proceedings. States should therefore also provide for separate, albeit related, mens rea and diminished capacity defenses.
  • “Guilty but mentally ill” verdicts are ineffective and unjust.  States should neither replace the insanity defense with this disposition nor offer it as an alternative to judges and jurors considering an insanity defense.
  • People acquitted because of a finding of insanity should be treated in an appropriate clinical setting, identically to civil committees, and governed only by civil mental health codes. The purpose of this treatment should be rehabilitative, not punitive.
  • Because of the weighty implications of the decision to plead insanity, the defendant must be the one to decide whether to use the insanity defense.  However, courts should act to ensure that the defendant is capable of understanding the consequences of the decision, and inform them in open court of those consequences.
  • Because appreciation of mental health conditions and their effect on decision-making goes to the essence of criminal intent, people with mental illness should have access to specialized courts with mental health expertise and a comprehensive understanding of treatment alternatives in dealing with both criminal and civil justice issues.

The Mental Health America Board of Directors approved this policy on June __, 2020. It will remain in effect for five (5) years and is reviewed as required by the Mental Health America Public Policy Committee.


Expiration: December 31, 2025

1 Livermore, Joseph and Paul Meehl, “The Virtues of M’Naghten,” Minnesota Law Review Vol. 51, pages 789-856: 790-793 (1967), .

2 Winkel, Susan. “Free Fill, Responsibility & Forensic Psychiatry: An Exploration of Justifications for the Insanity Defense.”  GGzet Wetenschappelijk, Vol. 17: 1: 36, 44 (2013), no PubMed citation found.

3 Durham v. United States, 214 F.2d 862 (D.C. Cir. 1954),

4 Bonnie, Richard. “The Moral Basis of the Insanity Defense,” American Bar Association Journal, Vol. 69, No. 2: 794, 795 (1983),


6 Robinson, Paul, “An Overview of Mental Illness under U.S. Criminal Law,” University of Pennsylvania Law School, Public Research Paper, 2 (2013), unpublished.

7 548 U.S. 735 (2006),


9, standard 7-6.9

10 395 U.S. 238,

11 Boykin, 395 US at 243

12 Ellis, James, “The Consequences of the Insanity Defense: Proposals to Reform Post-Acquittal Commitment Laws,” Catholic University Law Review, Vol. 35: 961, 1019 (1986), available at .

13 Reisner, Andrew, et al., “Competency to Stand Trial and Defendants Who Lack Insight into Their Mental Illness,” American Academy Psychiatry Law Journal, Vol. 41: 85, 86 (2013), .

14 American Bar Association mental health standards


16 See Jones v. U.S., 463 U.S. 354, 370 (1983),,+463+U.S.+354&hl=en&as_sdt=4006&as_vis=1 .

17 Silver, Eric. “Demythologizing Inaccurate Perceptions of the Insanity Defense,” American Psychiatric Association Journals, Law and Human Behavior, Vol. 18, No. 1: 63, 63 (1994), .

18 504 U.S. 71 (1992),

19 Hafemeister, Thomas and Petrila, John, “Treating the Mentally Disordered Offender: Society’s Uncertain, Conflicted, and Changing Views,” Florida State University Law Review, Vol. 21: 729, 749-750 (1993), ; Shaefer, Michele and Bloom, Joseph, “The Use of the Insanity Defense as a Jail Diversion Mechanism for Mentally Ill Persons Charged with Misdemeanors,” American Academy of Psychiatry Law Journal, Vol. 33: 79, 81 (2005), .


21 Costanzo, Mike and Daniel Krauss. Forensic and Legal Psychology, Worth Publishers, 206 (2012).

22 Braff, Jeraldine, et al., “Detention Patterns of Successful and Unsuccessful Insanity Defendants,” Criminology, Vol. 21, No. 3: 439-446 (1983), available at .

23 Robinson, Paul and Markus Dubber. An Introduction to the Model Penal Code. University of Pennsylvania Law School. Available at    

24 State Court Organization, The Defense of Insanity: Standards and Procedures. Department of Justice. Table 35, 209-212 (2004). Available at ;  Lillienfeld, Scott and Hal Arkowitz. The Insanity Verdict on Trial, Scientific American, Dec. 23, 2010,

25 Robitscher, Jonas and Andrew Haynes, “In Defense of the Insanity Defense,” Emory Law Review, Vol. 31: 9, 59 (1982), .

26 See Clark v. Arizona, 548 U.S. 735, 755 (2006), .

27 See Delling v. Idaho, 133 S.Ct. 504, 504 (2012), .


29 Arenella, Peter. The Diminished Capacity and Diminished Responsibility Defenses: Two Children of a Doomed Marriage, Columbia Law Review, Vol. 77, No. 6: 827, 829 (1977), .

30 Parry, John and Eric Drogin, “Mental Disability Law, Evidence, and Testimony,” American Bar Association, 207 (2007), .

31 Id. at 208.

32 Clark v. Arizona, 548 U.S. 735 (2006), 779, .

33 Parry, op. cit., at 209.

34 Clark v. Arizona, 548 U.S. 797 (Kennedy, J., dissenting) (emphasis added), .

35 Kahler v. Kansas, 140 S.Ct. 1021, 206 L.Ed. 2d 312, 2020 LEXIS 1910 (2020)

36 See People v. Crews, 122 Ill.2d 266, 294 (1988); State v. Anderson, 966 So.2d 973, 984 (2008).

37 See Estelle v. Gamble, 97 S.Ct. 285, 291 (1976),   (holding that deliberate indifference to prisoner’s serious medical needs constitutes a violation of the 8th Amendment’s prohibition against cruel and unusual punishment). See also Brown v. Plata, 131 S.Ct 1910, 1947 (2011)  (Reaffirming that the 8th Amendment requires the state to provide medical treatment, specifically mental health treatment, to prisoners).

38 See, e.g., 730 ILCS 5/5-2-6,

39 Smith, S “Neuroscience, Ethics, and Legal Responsibility: The Problem of the Insanity Defense.” Journal of Science and Engineering Ethics, Vol 18(3): 475-481, 478 (2012), .

40 Melville, John and David Naimark. “Punishing the Insane: The Verdict of Guilty but Mentally Ill, American Academy of Psychiatry Law Journal, Vol. 30: 553, 553 (2002), 

41 See, e.g., People v. Lantz, 186 Ill.2d 243, 255,   (Reversing an appellate court decision that held that Illinois’s GBMI law violates due process).

42 Kutys, Jennifer and Jennifer Esterman. Guilty but Mentally Ill (GBMI) vs. Not Guilty by Reason of Insanity (NGRI): An Annotated Bibliography. The American Society of Trial Consultants. The Jury Expert, 28, .


Note: 36, 37, and 38 are missing


[36] Ellis, James. “The Consequences of the Insanity Defense: Proposals to Reform Post-Acquittal Commitment Laws. Catholic University Law Review,” Vol. 35: 961, 1019 (1986), no PubMed citation available.

[37] Reisner, Andrew, et al., “Competency to Stand Trial and Defendants Who Lack Insight into Their Mental Illness,” American Academy Psychiatry Law Journal, Vol. 41: 85, 86 (2013), .

[38] See, e.g. Ross v. Inslee, __ U.S. __ (E.D. Wash 2014), , .