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  • Michael Mullan

Statistics on Mental Illness & the Insanity Defense


· Insanity defense used in less than 1% of felony cases, and only successful in even lesser of a percentage.[1]

· Rate of mental health in prisons: 2006 report by the Department of Justice reported that 15 percent of inmates of state prisons were psychotic.[2]

Rate of mental illness in jails: 24 percent of jail inmates had symptoms of a psychotic disorder. [3]

jails in Maryland and New York in 2002-2006, 16.7 percent of jail inmates exhibited symptoms of serious mental illness (schizophrenia, schizoaffective,

bipolar, major depression, brief psychotic disorder) within the previous month.[4]

“Thus, the total number of prison and jail inmates who were seriously mentally ill in 2012 would total approximately 356,000 inmates. This is equivalent to the population of cities such as Anchorage, Alaska; Montgomery, Alabama; Peoria, Illinois; or Trenton, New Jersey.”[5]

· one in five prisoners were seriously mentally ill[6]

· 7.2 percent of jail inmates appeared to have a serious mental illness[7]

· “On any given day, at least 284,000 schizophrenic and manic depressive individuals are incarcerated, and 547,800 are on probation”[8]

· "Approximately a quarter million individuals with severe mental illnesses are incarcerated at any given moment ..."[9]

· Prevalence of MI “among jail detainees is higher for men by more than three times[10] (1.8 vs. 6.4%;; and almost twice as high as for women (Mw = 10.6 vs. 20.4%;[11]

· " number of people under correctional supervision in the USA recently reached an all-time high of 7.3 million"[12]

· "a meta-analysis of 62 studies suggests that 14% of offenders suffer from a major mental illness.[13] If so, then there are over one million individuals with mental illness in the USA in jail, in prison, on probation, or on parole."

· Prisons and jails “well over 350,000 inmates with serious mental illness compared to approximately 70,000 patients with serious mental illness in hospitals.” [14]

· "up to 20 percent of those incarcerated meet diagnostic criteria for a serious mental disorder, with about 5 percent having psychotic disorders”[15]

· “6.7% of prisoners had experienced symptoms of schizophrenia at some point in their lives.”[16]

· “Canada...DSM-III-R criteria found a 7.7% prevalence of psychotic disorders in a sample of 9,801 inmates”[17]

· "Great Britain found a tenfold higher prevalence of psychotic disorders among prisoners”[18]


· 450 million people world wide suffer from mental or behavioural disorders.[19]

· in any given year one quarter of adults living in the United States are diagnosable for one or more mental disorders.”[20]

· Serious mental illness: 6% of adults (1 in 17) in the United States.[21]

· 1% of globe and US have schizophrenia[22]


· Deinstiutionalization: "from 1955 to 1980, the number of persons institutionalized in mental health facilities declined by 75%." [23]

· “1950 to 2000… the proportion of people with SPMI living in psychiatric institutions dropped by 23%, whereas the proportion living in correctional institutions rose only 4%. The rise in incarceration rates for those with SPMI follows a predictable pattern, remaining at 1% from 1950 to 1970, but rising to 3% by 1990 and 5% by 2000.”[24]

· “in 1960, about 563,000 beds were available in U.S. state and county psychiatric hospitals (314 beds per 100,000 persons), with about 535,400 resident patients. By 1990, the number of beds declined to about 98,800 (40 per 100,000) and the number of residents to 92,059”[25]

· “an overall increase (from 8 percent to 11 percent) in the percentage of prison inmates with prior mental hospitalization between 1968 and 1978”[26]


· 86% of insanity pleas occur in nonviolent crimes[27]

· less than one third of the successful pleas were homicide related offenses[28]


· NGRI acquittees spend almost double the amount of time in confinement (in hospital rather than prison)[29]


· "In an eight-state study involving nearly 9,000 defendants who pleaded NGRI... found an acquittal rate of 25%."[30]

· “acquittal rates of 20% to 25%” [31]

· “10% of insanity acquittals were in relation to misdemeanors.”[32]

· 80% [of successful insanity defenses] “were uncontested by the prosecutor and disposed of informally without trial.” [33]


· Cost of treating serious mentally ill in prison as opposed to hospital: “individuals cost the taxpayers twice as much as individuals with schizophrenia and bipolar disorder who were not involved in the criminal justice system.”[34]


· Prison rule violations: “mentally ill jail inmates were twice as likely (19 percent versus 9 percent) to be charged with facility rule violations…. Washington State prisons, mentally ill inmates accounted for 41 percent of infractions, although they constituted only 19 percent of the prison population. In a county jail in Virginia, 90 percent of assaults on deputies were committed by mentally ill inmates.[35]

· Suicides in prison: “A study of 132 suicide attempters in the King County, Washington, jail system reported that 77 percent of them had a ‘chronic psychiatric problem’ ” In Cali, of 154 suicides, “73 percent had a history of mental health treatment.” [36]

· “only about half of all inmates with mental illness receive treatment”[37]

· Of those prisoners who have a mental illness in prison, only 1/3 get any treatment.[38]


· Recidivism & hospitalization: LA County Jail 88 percent of the mentally ill inmates had had a previous psychiatric hospitalization, and 95 percent had had a previous arrest.[39]

· one in five re-arrest within 18 months of jail diversion program starting[40]

· GENERAL RECIDIVISM not related to MI….55% of all felony offenders in the study were not convicted of a subsequent offense during three years following their initial arrest and finding that homicide offenders had one of the lowest recidivism rates[41]


· “nearly three out of every four jail detainees with a serious mental illness have a co-occurring substance abuse disorder”[42]

· “about one-half to three-fourths of persons who had an alcohol, or other substance-related disorder throughout their lifetimes had at least one other mental disorder”[43]


· “one-third of homeless persons meet diagnostic criteria for a major mental illness”[44]


· probability that mental illness caused the offense. Direct and indirect effects were defined as the influence of delusions or hallucinations, or any other symptom (e.g., confusion, depression, irritability etc.),. …8% had been arrested for offenses that their psychiatric symptoms probably-to-definitely caused, either directly (4%) or indirectly (4%). [45]


· “psychotic disorders are arrested more frequently”[46]

· "mentally ill suspects are about 20 percent more likely to be arrested than their counterparts”[47].

· 70% of all people under the control of the criminal justice system are “supervised in the community on probation or parole”[48]


· “schizophrenia are arrested for minor crimes, such as disturbing the peace and public intoxication”[49]

· "used primarily in murder cases... one third of successful insanity pleas."[50]


· Among patients with schizophrenia, there was a “74% medication discontinuation rate”[51]


[1] Lisa A. Callahan, Henry J. Steadman, Margaret A. McGreevy, & Pamela Clark Robbins, The Volume and Characteristics of Insanity Defense Pleas: An Eight-State Study, 19 Bull Am Acad Psychiatry Law (1991) 4, at 333.

[2] Doris J. James and Lauren E. Glaze, Mental Health Problems of Prison and Jail Inmates, September 2006, NCJ 213600).

[3] Doris J. James and Lauren E. Glaze, Mental Health Problems of Prison and Jail Inmates, September 2006, NCJ 213600).

[4] Steadman et al., Prevalence of serious mental illness among jail inmates, Psychiatric Services 2009;60:761–765)

[5] E. Fuller Torrey et al., The Treatment of Persons with Mental Illness in Prisons and Jails: A State Survey (TAC, 2014), at 101.

[6] American Psychiatric Association, Psychiatric Services in Jails and Prisons. (2000) Washington, D.C.: American Psychiatric Association, at xix.

[7] Torrey, E. F., J. Stieber, J. Ezekiel, S. M. Wolfe, J. Sharfstein, J. H. Noble, and L. M. Flynn. 1992. Criminalizing the Seriously Mentally Ill. Washington, D.C.: National Alliance for the Mentally Ill and Public Citizen Health Research Group.

[8] The Impact of the Mentally Ill on the Criminal Justice System: Hearing Before the House Judiciary Subcomm. on Crime, 106th Cong. (2000) (testimony of Congressman Ted Strickland), as cited in Re-Arranging the Deck Chairs, at 2.

[9] Robert Bernstein & Tammy Seltzer, Criminalization of People with Mental Illnesses: The Role of Mental Health Courts in System Reform, 7 UDC L. REV. 143, 145 (2003).

[10] Teplin, L. (1990). The prevalence of severe mental disorder among urban male jail detainees: Comparison with the epidemiologic catchment area program. American Journal of Public Health, 80, 663–669. doi:10.2105/AJPH.80.6.663

[11] Teplin, L. A., Abram, K. M., & McClelland, G. M. (1996). Prevalence of psychiatric disorders among incarcerated women: Pretrial jail detainees. Archives of General Psychiatry, 53(6), 050–512. Retrieved from

[12] Bureau of Justice Assistance. (2009). Improving responses to people with mental illness: The essentials of a mental health court. Retrieved on February 3, 2009 from

[13] Fazel, S., & Danesh, J. (2002). Serious mental disorder in 23,000 prisoners: A systematic review of 62 surveys. Lancet, 359, 545–550. doi:10.1016/S0140-6736(02)07740-1.; see also Steadman, H., Osher, F., Robbins, P., Case, B., & Samuels, S. (2009). Prevalence of serious mental illness among jail inmates. Psychiatric Services, 60, 761–765. doi:10.1176/

[14] State Advocacy, NAMI, Section=state_Advocacy&Template=/ ContentManagement/ContentDisplay.cfm&ContentID=93161

[15] Roth, L. H. 1980. Correctional psychiatry. In W. Curran, A. McGarry, and C. Petty (eds.), Modern Legal Medicine, Psychiatry, and Forensic Science. Philadelphia: Davis.

[16] Robins LN, Regier DA: Psychiatric Disorders of America: The Epidemiologic Catchment Area Study. New York, Free Press, 1991.

[17] Motiuk LL, Porporino FJ: The Prevalence, Nature and Severity of Mental Health Problems Among Federal Male Inmates in Canadian Penitentiaries. Ottawa, Ontario, Canada, Correctional Service of Canada, 1991

[18] Brugha T, Singleton N, Meltzer H, et al: Psychosis in the community and in prisons: a report from the British national survey of psychiatric morbidity. American Journal of Psychiatry 162:774–780, 2005 ).

[19] World Health Report 2001: Mental Health: New Understanding, New Hope. Geneva, World Health Organization.

[20] Any Disorder Among Adults, Nat’l Inst. Mental Health (NIMH),

[21] Any Disorder Among Adults, Nat’l Inst. Mental Health (NIMH),

[22] Schizophrenia, NIMH, http://

[23] William Gronfein, Incentives and Intentions in Mental Health Policy: A Comparison of Medicaid and Community Mental Health Programs, 26 J. Health & Soc. Behav. 192, 196 (1985) at 192.

[24] Frank, R., & Glied, S. (2006). Mental health policy in the United States since 1950: Better but not well. Baltimore, MD: The Johns Hopkins University Press.)

[25] National Institute of Mental Health. 1990. Mental Health, United States. Washington, DC: U.S. Government Printing Office.

[26] Steadman, Henry J., and Richard B. Felson. 1984. Self-reports of violence: Ex-mental patients, ex-offenders, and the general population. Criminology 22:321-342.

[27]Elizabeth Nevins-Saunders, Not Guilty as Charged: The Myth of Mens Rea for Defendants with Mental Retardation, 45 U.C. Davis L. Rev. 1419 (2012) , at 1454 n. 172 (discussing NAT'L MENTAL HEALTH ASS'N, MYTHS & REALITIES: A REPORT OF THE NATIONAL COMMISSION ON THE INSANITY DEFENSE 20-21 (1983).

[28] Rodriguez, LeWinn & Perlin, supra note 20, at 402; Anne Singer, Insanity Acquittal in the Seventies: Observations and Empirical Analysis of One Jurisdiction, 2 MENT. DIS. L. REP. 407 (1977)

[29] Joseph Rodriguez, Laura LeWinn & Michael L. Perlin, , The Insanity Defense Under Siege: Legislative Assaults and Legal Rejoinders, 14 RUTGERS L.J. 397, 400 (1983), at 403–04. See also Grant T. Harris et al., Length of Detention in Matched Groups of Insanity Acquittees and Convicted Offenders, 14 INT’ L J.L. & PSYCHIATRY 223 (1991).

[30] Callahan, L. A., Steadman, H. J., McGreevy, M. A. & Robbins, P. C. 1991 The volume and characteristics of insanity defense pleas: An eight-state study. Bulletin of Psychiatry and the Law 19. QUOTE FROM and Referred to by Curt R. Bartol & Anne M. Bartol ], Psychology and Law: research and practice. SAGE publications 2015, at 119.

[31] Cirincione, C., Steadman, H., McGreevy, M. 1995 Rates of insanity acquittals and the factors associated with successful insanity pleas. Bulletin of the American academy of Psychiatry and Law 23; Pasewark, R. & McGinley, H. 1986 Insanity Plea: National survey of frequency and success. journal of Psychiatry and Law 13; Callahan, L. A., Steadman, H. J., McGreevy, M. A. & Robbins, P. C. 1991 The volume and characteristics of insanity defense pleas: An eight-state study. Bulletin of Psychiatry and the Law 19.

[32] Cirincione, C. & Jacobs, c. 1999 identifying insanity acquittals: is it any easier? Law and human behavior 23.

[33] Rogers, R., Cavanaugh, J. L., Seman, W. & Harris, M. 1984 Legal outcome and clinical findings: a study of insanity evaluations. bulletin of the American academy of psychiatry and law 12..

[34] J. W. Swanson, L. K. Frisman, A. G. Robertson et al., Costs of criminal justice involvement among persons with serious mental illness in Connecticut, Psychiatric Services 2013;64:630–637

[35] Criminal Justice / Mental Health Consensus Project, Fact Sheet: Mental illness and jails; C. Turner, Ethical issues in criminal justice administration, American Jails 2007;20:49–53;

[36] R. F. Patterson and K. Hughes, Review of completed suicides in the California Department of Corrections and Rehabilitation, 1999–2004, Psychiatric Services 2008;59:676–82.; Goss, J.R., Peterson, K., Smith, L.W., Kalb, K., Brodey, B.B. (2002). Characteristics of suicide attempts in a large urban jail system with an established suicide prevention program. Psychiatric Services, 53, 574–579.

[37] Ditton PM: Mental Health and Treatment of Inmates and Probationers. Washington, DC, US Department of Justice, Office of Justice Programs, 1999.

[38] Campaign for the Fair Sentencing of Youth et al., Criminal and Juvenile Justice 5-6 (2010), available at http:// Criminal%20Justice%C20Joint%C20Report%20USA.pdf

[39] H. R. Lamb, L. E. Weinberger, J. S. Marsh et al., Treatment prospects for persons with severe mental illness in an urban county jail, Psychiatric Services 2007;58:782–86.,

[40] Boccaccini, M., Christy, A., Poythress, N., & Kershaw, D. (2005). Rediversion in two postbooking jail diversion programs in Florida. Psychiatric Services, 56, 835–839. doi:10.1176/

[41] Office of the Legislative Auditor, State of Minnesota, Recidivism of Adult Felons, available at

[42] Abram, K., & Teplin, L. (1991). Co-occurring disorders among mentally ill jail detainees: Implications for public policy. American Psychologist, 46, 1036–1045. doi:10.1037/0003-066X.46.10.1036.; Abram, K., Teplin, L., & McClelland, G. (2003). Co-morbidity of severe psychiatric disorders and substance use disorders among women in jail. American Journal of Psychiatry, 150, 1007–1010. doi:10.1176/appi.ajp.160.5.1007.

[43] Kessler, Ronald C., Katherine A. McGonagle, Shanyang Zhao, Christopher B. Nelson, Michael Hughes, Suzann Eshleman, Hans- Ulrich Wittchen, and Kenneth S. Kendler. 1994. Lifetime and 12-month prevalence of DSM-III-R psychiatric disorders in the United States: Results from the National Comorbidity Survey. Archives of General Psychiatry 51:8-19

[44] Jencks, Christopher. 1994. The Homeless. Cambridge, MA: Harvard University Press. ; Lamb, H. Richard. 1992a. Deinstituionalization in the nineties. In Richard Lamb, Leona Bachrach, and Frederic Kass (eds.), Treating the Homeless Mentally Ill. Washington, DC: American Psychiatric Association. Shlay, Anne B., and Peter H. Rossi. 1992. Social science research and contemporary studies of homelessness. Annual Review of Sociology 18:129-160.

[45] Junginger, J., Claypoole, K., Laygo, R., & Cristiani, A. (2006). Effects of serious mental illness and substance abuse on criminaloffenses. Psychiatric Services, 57, 879–882. doi:10.1176/

[46] Teplin LA: Criminalizing mental disorder: the comparative arrest rate of the mentally ill. American

Psychologist 39:794–803, 1984.

[47] Teplin, Linda A. 1984. Criminalizing mental disorder: The comparative arrest rate of the mentally ill. American Psychologist 39:794-803

[48] Glaze, L., & Bonczar, T. (2007). Probation and parole in the United States, 2006. Washington, D.C.: U.S. Department of Justice, Bureau of Justice Statistics

[49] Valdiserri E, Carroll K, Hartl A: A study of offenses committed by psychotic inmates in a county jail. Hospital and Community Psychiatry 37:163–166, 1986.

[50] Mackay, Mental condition Defences in Criminal Law (1995), at 112.

[51] Lieberman J, Stroup T, McEvoy J, et al: Efectiveness of antipsychotic drugs in patients with chronic schizophrenia. New England Journal of Medicine 353:1209– 1223, 2005.

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Jerome CAGE
Jerome CAGE
Feb 23


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