States adopted the Guilty but Mentally Ill (GBMI) verdict following concerns about the Not Guilty by Reason of Insanity (NGRI) defense.
Those found GBMI are subject to the same sentences as those found guilty and may or may not receive mental health treatment.
After GBMI was introduced the number of NGRI pleas did not decrease, but they were less likely to lead to insanity acquittals.
In 1981 John Hinkley Jr., shot President Ronald Reagan wounding him and three others. Hinkley was found not guilty by reason of insanity (NGRI). Following a public outcry from the Hinkley case many states modified their insanity plea laws. Reforms included changing the test for legal insanity and moving the burden of proving insanity to the defendant (Callahan et al. 1987). An additional reform was adopting the Guilty but mentally ill (GBMI) verdict. GBMI offers an alternative verdict that acknowledges a defendant's mental illness but does not absolve them of criminal responsibility (National Center for State Courts 1985). GBMI requires the defendant to have been guilty of the offense, and to be mentally ill, but not legally insane when the offense was committed (Woodmansee 1996). There are 13 states with a GBMI verdict option (Palmer & Hazelrigg 2000; Figure 1) GBMI was enacted with the goals of preventing the early release of dangerous offenders, holding them responsible for their crimes, and to get mental health treatment to offenders who needed it (Klofas & Weisheit 1987). AK, GA, IN, SD, and UT adopted this policy following prominent violent crimes, including some committed after the perpetrator had been released from a mental hospital following a NGRI finding (National Center for State Courts 1984).
Figure 1. States with a GBMI verdict. GBMI data is from Palmer & Hazelrigg (2000), NGRI data is from Sanabria (2023)
Most states have an NGRI defense. MT, KS, ID, UT do not (Sanabria 2023) . In a NGRI defense, the defendant admits to committing the act but is not culpable due to mental illness. Insanity defenses vary in their standard for insanity, as well as if the burden of proof falls on the state or the defendant (Sanabria 2023). A common test requires the accused to not know the nature of the act, or to not know that it was wrong (Legal Information Institute 2023).
Despite the defendant being found not guilty, an NGRI acquittal still often results in their confinement (Borum & Fulero 1999). Those found NGRI are usually committed to a psychiatric facility, at least for evaluation, or for a term, which can be as long or longer than those sentenced to prison on equivalent charges (Borum & Fulero 1999). In MO, persons acquitted by reason of insanity are usually hospitalized in a MO Department of Mental Health psychiatric hospital (Linhorst & Dirks-Linhorst 1997). In GA, 98% of those found NGRI were sent to psychiatric hospitals, whereas 80% and 20% of those found GBMI were sent to prison and sentenced to probation, respectively (Callahan et al. 1992).
In contrast to NGRI, a defendant found GBMI is subject to the same punishment as one found guilty. In GA, those found GBMI received harsher punishment, including longer sentences compared to those found guilty (Callahan et. al 1992). For those found guilty of murder, a typical sentence was five years longer. A GBMI verdict does not always guarantee mental health treatment (National Center for State Courts 1985). In MI, prisoners may receive mental health care with the Department of Corrections or the Department of Mental Health following a mental health evaluation (Palmer & Hazelrigg 2000). IL does not require treatment and GA only requires it as appropriated funds permit ( Woodmansee 1996). Three states (AK, KY, and SC) require mental health treatment (Woodmansee 1996). Those found GBMI have similar prison experiences to those found guilty. A study at a women’s prison in MI did not find differences in the number of violent incidents or the amount of time spent in prison inpatient mental health treatment between GBMI and guilty first year prisoners (Naidoo et al. 2018).
Following IL’s introduction of GBMI, the number of NGRI findings did not decrease (Klofas & Weisheit 1987). In GA, the rate of NGRI pleas did not change, however those pleading insanity were less likely to be acquitted, particularly for violent offenders. (Callahan et al. 1992). For those pleading NGRI, the percentage of guilty verdicts and NGRI verdicts declined, indicating that GBMI partially substituted for both (Callahan et al. 1992). Unlike NGRI, the majority of GBMI sentences in IL and MI resulted from plea bargaining (Klofas & Weisheit 1987, Smith & Hall 1982).
The GBMI verdict may not be clearly understood by jurors. In states with both NGRI and GBMI, jurors must decide between a defendant being legally insane or being mentally ill (Cotrone 2016). Jurors may not have a good understanding of the distinction between NGRI and GBMI, in a study of prospective jurors, participants could not correctly identify the definition of GBMI 63% of the time, and NGRI 44% of the time (Sloat & Frierson 2005). Jurors are usually not informed of sentencing consequences and 63% were able to correctly identify the outcome of a GBMI verdict.
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National Center for State Courts (1984) The Guilty but mentally ill verdict: An Empirical Study. U.S. Department of Justice. https://www.ojp.gov/pdffiles1/Digitization/98813NCJRS.pdf
Palmer CA, Hazelrigg M (2000) The guilty but mentally ill verdict: A review and conceptual analysis of intent and impact. The Journal of the American Academy of Psychiatry and the Law (28)1:47-54. https://pubmed.ncbi.nlm.nih.gov/10774841/
Sanabria L (2023) The Insanity Defense Among the States. https://www.findlaw.com/criminal/criminal-procedure/the-insanity-defense-among-the-states.html
Sloat LM, Frierson RL (2005) Juror Knowledge and Attitudes Regarding Mental Illness Verdicts. The Journal of the American Academy of Psychiatry and the Law (33)2: https://jaapl.org/content/33/2/208
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Woodmansee MA (1996) The Guilty but Mentally Ill Verdict: Political Expediency at the Expense of Moral Principle. Notre Dame Journal of Law, Ethics & Public Policy (1)9:341-387. http://scholarship.law.nd.edu/ndjlepp/vol10/iss1/9
