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Overrepresentation of People with Mental Illness in the Criminal Justice System
Today, there are approximately 2 million people incarcerated in US prisons or jails[1]; approximately 10 million people are booked into US jails over the course of the year.[2]


Approximately 5 percent of the US population has a serious mental illness.[3] The US Department of Justice reports, however, that about 16 percent of the population in prison or jail has a mental illness.[4]


A study conducted in New York State found that men involved in the public mental health system over a five-year period were four times as likely to be incarcerated as men in the general population; for women the ratio was six to one.[5]


The Los Angeles County Jail, the Cook County Jail (Chicago) and Riker's Island (New York City) each hold more people with mental illness on any given day than any hospital in the United States.[6]


Nearly three-quarters of inmates with mental illness have a co-occurring substance abuse problem.[7]


Inmates with mental illness in state prison were 2.5 times as likely to have been homeless in the year preceding their arrest than inmates without a mental illness.[8]


Nearly half the inmates in prison with a mental illness were incarcerated for committing a nonviolent crime.[9]



Length of Stay Once Incarcerated
On average, inmates with mental illness serve a longer portion of their sentence than inmates without mental illness.[10]


On Riker's Island (New York City's largest jail), the average length of stay for an inmate is 42 days; it is 215 days for an inmate with a serious mental illness.[11]


In 2000 in Pennsylvania, 16 percent of all releasees served their maximum sentence. If an inmate had a mental illness, he/she was twice as likely to serve his/her maximum sentence than other inmates; having a serious mental illness meant the inmate was three times as likely to serve his/her maximum sentence.[12]



Statewide Commissioners/Task Forces Regarding Mental Illness and the Criminal Justice System
Within the last four years, almost half of the states have established special commissions or task forces to look into some aspect of the mental health system. Legislation calling for the establishment of such bodies has been introduced in an additional 5 states.13


Almost half of these commissions are explicitly charged with investigating the criminalization of mental illness.[14]


Officials in King County, Washington, identified 20 people who had been repeatedly hospitalized, jailed or admitted to detoxification centers; in the course of one year, providing these emergency services to these 20 individuals cost the county at least $1.1 million.[15]



Innovative Programs' Impact on Costs and Public Safety
Staff from the Thresholds Jail Program, which provides case management for people with mental illness released from jail in Cook County Illinois, calculated the number of days that 30 people who had been through the program were incarcerated and/or hospitalized in the year after their participation in the program. In total, the 30 individuals spent approximately 2,200 days less in jail (at $70/day) than they had during the year preceding their participation in Thresholds. These same 30 people also spent about 2,100 fewer days (at $500/day) in hospitals.[16]



Using Law Enforcement Resources More Efficiently
In Memphis, Tennessee, before the implementation of their Crisis Intervention Team (CIT) model, officers spent 4-6 hours at the medical center for mental health admissions, which now average about 15 minutes. Shortly after the Memphis CIT was implemented, injuries suffered by individuals with mental illnesses caused by police decreased by nearly 40 percent.[17]


In 1999, the Albuquerque Police Department, which also employs a CIT model, reported that officers arrested, transported to jail, or otherwise took into protective custody fewer than 10 percent of those people with mental illnesses they contacted. Injuries were also reduced to just more than 1 percent of calls after their CIT model was implemented. The decrease in use of SWAT was reported at 58 percent.[18]



Violence, Mental Illness, and Victimization
The results of several, large-scale research projects conclude that only a weak statistical association between mental disorder and violence exists. Serious violence by people with major mental disorders appears concentrated in a small fraction of the total number, and especially among those who use alcohol and other drugs.[19]


When a person with mental illness commits a violent crime, more than half the time, the victim is a family member, a friend, or an acquaintance.[20]


One study in North Carolina found that people with mental illness are almost three times as likely to be victims of violent crime than people without mental illness.[21]



Not-Guilty-by-Reason -of-Insanity
The public and the media often associate mental illness and the criminal justice system with pleas of not guilty by reason of insanity (or under new state laws, a conviction of guilty but insane). A small fraction of defendants with mental illness make such pleas. A 1996 study of the Baltimore Circuit Court estimated that of 60,342 indictments filed during one year, only 8 defendants (.013 percent) ultimately pleaded not criminally responsible. All 8 pleas were uncontested by the state.[22]



[1] Allen J. Beck, Jennifer C. Karberg, Prison and Jail Inmates at Midyear 2000, Washington, DC: U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, 2000.

[2] Bureau of Justice Statistics, Correctional Populations in the United States 1997, Washington, DC: U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, 1997.

[3] R. C. Kessler et al., "A Methodology for Estimating the 12-Month Prevalence of Serious Mental Illness," In Mental Health United States 1999, edited by R.W. Manderscheid and M.J. Henderson, Rockville, MD, Center for Mental Health Services.

[4] Paula.M. Ditton, Mental Health Treatment of Inmates and Probationers, Washington DC: U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, July 1999.

[5] Judith F. Cox, Pamela C. Morschauser, Steven Banks, James L. Stone, "A Five-Year Population Study of Persons Involved in the Mental Health and Local Correctional Systems," Journal of Behavioral Health Services & Research 28:2, May 2001, pp. 177-87.

[6] E. Fuller Torrey, "Reinventing Mental Health Care," City Journal 9:4, Autumn 1999.

[7] Linda Teplin and Karen Abram, "Co-Occurring Disorders among Mentally Ill Jail Detainees: Implications for Public Policy," American Psychologist 46:10, pp. 1036-45.

[8] Ditton, Mental Health and Treatment.

[9] Ibid.

[10] Ibid.

[11] Fox Butterfield, "Prisons Replace Hospitals fro the Nation's Mentally Ill,"New York Times, March 5, 1998, A1. Refers to testimony of Dr. Arthur Lynch, director of Mental Health Services for the NYC Health and Hospiutals Corporation, before the Subcommittee on Mental Health, Mental Retardation, Alcoholism and Drug Abuse Service (April 22, 1998).

[12] From unpublished description of Forensic Community Re-Entry and Rehabilitation for Female Prison Inmates with Mental Illness, Mental Retardation, and Co-occurring Disorders program, courtesy of Angela Sager, grants manager, May 12, 2002.

[13] See www.csgeast.org/programs/criminal_justice/statewide_commissions.htm

[14] Ibid.

[15] Unpublished data courtesy of Patrick Vanzo, Section Chief, Crisis and Engagement Services, Mental Health, Chemical Abuse and Dependency Services Division, King County Dept.of Community and Human Services

[16] Information available at: www.thresholds.org.

[17] B. Vickers, "Memphis, Tennessee Police Department's Crisis Intervention Team," Bulletin from the Field, Practitioner Perspectives, U.S. Department of Justice, Bureau of Justice Assistance, Available at: www.ncjrs.org/pdffiles1/bja/182501.pdf.

[18] D.L. Bower W. G. and Pettit, "The Albuquerque Police Department's Crisis Intervention Team," FBI Law Enforcement Bulletin, February 2001, available at: www.fbi.gov/publications/leb/2001/feb01leb.pdf.

[19] H. Steadman, E. Mulvey, J. Monahan, P Robbins, P. Applebaum,, T. Grisso, L. Roth, and E. Silver, "Violence by People Discharged From Acute Psychiatric Inpatient Facilities and by Others in the Same Neighborhoods. Archives of General Psychiatry 55, 1998, pp. 393-401. See also K.T. Meuser, et. al., "Trauma and Post-Traumatic Stress Disorder in Severe Mental Illness," Journal of Consulting and Clinical Psychology 66:3, 1998, 493-99.

[20] Ditton, Mental Health and Treatment, 4.

[21] Virginia Hiday, Marvin S. Swartz, Jeffery W. Swanson, Randy Borum, and H. Ryan Wagner, "Criminal Victimization of Persons with Severe Mental Illness," Psychiatric Services 50, 1998, pp. 62-68. This study tracked 331 involuntary mental health outpatients. The rate of nonviolent victimization for the study cohort (22.4 percent) was similar to that in the general population (22.1 percent). The rate of violent criminal victimization, however, was two and a half times greater than in the general population - 8.1 percent compared to 3.1 percent.

[22] Jeffrey S. Janofsky, Mitchell H. Dunn, Erik J. Roskes, Jonathan K. Briskin, Maj-Stina Rudolph Lunstrum, "Insanity Defense Pleas in Baltimore City: An Analysis of Outcome," American Journal of Psychiatry 153:11, November, 1996, pp.1464-68