It is vitally important for the chief to take an active leadership role in implementing agency-wide strategies to deal with persons coping with mental health issues or intellectual/developmental disabilities.

Police leaders need to focus on data-driven strategies to find effective solutions. There are many questions a chief needs to answer before moving forward, including the number of calls for service involving people with mental illnesses, available resources, training, information-sharing and privacy issues, and more.

To have successful interactions, the chief must be at the forefront as a leader on this issue, along with ensuring successful buy-in from officers throughout the agency, and strong, effective partnerships with mental health professionals. The PMHC program must be incorporated into agency goals and made an operational priority, taking its place on the chief's "dashboard." Support from all staff, top-to-bottom, is necessary for the efficacy and success of the PMHC program.

Issues related to people with mental illness need champions within the police agency, or else they run the risk of falling through the cracks. Some police agencies appoint an officer or commander to oversee the planning and implementation of the initiative. In addition, they serve as the agency's primary liaison with mental health providers and other stakeholders. These liaison officers can be particularly effective for problem-solving location-specific issues to reduce and prevent crimes, disorder, and calls for service at current and potential hot spots.

For additional information, see:

• Mental Health Officer Team Marks One-Year Anniversary with Exciting Additions
• Houston Police Department Mental Health Division
• Loudoun County Sheriff's Office

​Approximately 1 in 5 adults in the U.S.—43.8 million, or 18.5%—experiences mental illness in a given year, and approximately 1 in 25 adults in the U.S.—10 million, or 4.2%—experiences a serious mental illness in a given year that substantially interferes with or limits one or more major life activities (National Alliance on Mental Illness). 

The number of contacts law enforcement has with people with mental illnesses varies by community, and can be hard to document if the calls are not properly identified and coded.  An estimated 7 percent of police contacts in jurisdictions with 100,000 or more people are with individuals with mental illness (Deane, et al.). The majority of these encounters are with individuals suspected of committing low-level, misdemeanor crimes, or who are exhibiting nuisance behavior. Many communities report that the number of contacts has been increasing, sometimes precipitously, in recent years (San Diego Association of Governments).

People with mental illnesses, most of whom have co-occurring substance use disorders, are over-represented at every stage of the criminal justice system. Researchers documented serious mental illnesses in 14.5 percent of males in jail and 31 percent of females in jail (Steadman, et al.); these rates are more than three to six times those found in the general population (Kessler, et al). Generalized to the fact that almost 13 million jail admissions occur annually, more than 2 million bookings of people with serious mental illnesses occur annually (Snyder, et al).

For additional information, see:

• National Alliance on Mental Illness, "Mental Health by the Numbers."
• M. W. Deane, H. J. Steadman, R. Borum, B. M. Veysey, J. P. Morrissey, "Emerging Partnerships between Law Enforcement and Mental Health," Psychiatric Services, January 1999 Vol. 50 No. 1.
• H. J. Steadman, F. C. Osher, P. C. Robbins, B. Case, and S. Samuels, "Prevalence of Serious Mental Illness among Jail Inmates," Psychiatric Services 60, no. 6 (2009): 761-765.
• R. C. Kessler, C. B. Nelson, K. A. McKinagle, M. J. Edlund,  R. G. Frank,  and P. J. Leaf, "The Epidemiology of Co-Occurring Addictive and Mental Disorders: Implications for Prevention and Service Utilization," American Journal of Orthopsychiatry 6 (1996): 17–31.
• H. N. Snyder, W. J. Sabol, T. D. Minton, "Arrest in the United States, 1990–2010," (Washington, DC: Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, 2012).​​
• James D. Livingston, M.A., Ph.D. "Contact Between Police and People With Mental Disorders: A Review of Rates," Psychiatric Services 67, no. 8 (2016): 850-857.

Though tragic and violent incidents involving people with mental illness are rare, they draw intense media and public attention. This creates misperceptions about the relationship of mental illness to violence and unfortunately increased stigma and discrimination. There is no doubt that many individuals with mental illnesses who commit violent crimes must be held responsible for their actions. However, it is important to remember that most violence in this country is not committed by people who have a mental illness, and most people with mental illnesses are not violent.

The risk of violence statistically attributable to serious mental illness is estimated to be 3 to 5 percent; this is comparable to rates among persons without mental illnesses (Friedman). Because serious mental illness affects a small percentage of the population, it makes— at most—a very small impact on the overall level of violence in society. In fact, people with serious mental illnesses are anywhere from 2.5 times to nearly 12 times more likely to be victims rather than perpetrators of violence (Choe, et al; and Hiday, et al.).

For additional information, see:

• Richard A. Friedman, "Violence and Mental Illness—How Strong is the Link?" New England Journal of Medicine 355 no. 20 (2006), 2064–2066.
• J.Y. Choe, L. A. Teplin, and K. M. Abram, "Perpetration of Violence, Violent Victimization, and Severe Mental Illness: Balancing Public Health Concerns," Psychiatric Services 59, no. 2 (2008): 153–164.
• V.A. Hiday, J.W. Swanson, M.S. Swartz, R. Borum, and H.R. Wagner, "Criminal Victimization of Persons with Severe Mental Illness," Psychiatric Services 50, no. 4 (1999): 62–68.

When discussing people with mental illnesses in criminal justice settings, it is important to keep in mind the heterogeneity of this group. They differ in their demographics, seriousness of their mental illnesses, charge levels, access to commu​nity supports, and criminogenic risks (i.e., the factors that affect how likely they are to engage in criminal behavior). There are three primary factors that drive law enforcement encounters with people with mental illnesses: homelessness and visibility, substance use, and limited access to mental healthcare.

First, people with mental illnesses are over-represented in homeless populations and, as such, they are more visible to law enforcement. Their problematic behaviors (e.g., public disturbance, panhandling and public intoxication), which stem from lack of treatment, attract attention. As an indicator of how visibility may play a role in their arrest: incarcerated persons with mental illnesses are much more likely to have been homeless at the time of their arrest than those without mental illnesses (Ditton).

Second, people with mental illnesses are about three times more likely to develop a co-occurring substance use disorder than the general population (Reiger, et al.). This increased prevalence of substance use disorders over the course of their lifetimes, combined with an overall increase in arrests for drug-related offenses, means that more people with mental illnesses will be arrested. Research has found that nearly three-quarters of men and women with mental illnesses in jails also have a co-occurring substance use disorder (Abram and Teplin).

Third, the limited access to over-burdened community-based treatment may make individuals with untreated symptoms more likely to be arrested. Individuals with mental illness who encounter police are too frequently incarcerated—often for misdemeanant or non-violent infractions—rather than connected with treatment services, simply because of a lack of community resources. If there are no alternatives to incarceration for people with a serious mental illness, officers feel that their only option is to book that person into jail to ensure their safety.

For additional information, see:

• Paula Ditton, "Mental Health and Treatment of Inmates and Probationers," (Washington, D.C.: U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, 1999).
• D. Hasin and B. Kilcoyne, “Comorbidity of psychiatric and substance use disorders in the United States: current issues and findings from the NESARC,” Current Opinion in Psychiatry 25 no. 3 (May 2012): 165–171.​
• K. M. Abram and L. A. Teplin, "Co-Occurring Disorders among Mentally Ill Jail Detainees: Implications for Public Policy," American Psychologist 46, no. 10 (1991) 1036-45.
• German Lopez, "How America's Criminal Justice System became America's Mental Health System," Vox.com, March 1, 2016.