Why Determine the Prevalence of Mental Illnesses in Jails and Prisons?

To the Editor

Draine and Muñoz-Laboy’s (1) commentary on my review (2) in the July issue raises a point that is crucial (although they misattribute a motivating logic to my analysis): targeting an individual risk factor for incarceration, such as mental illness, will likely not reduce incarceration rates. This is because the causes of individual “cases” of incarceration are almost certainly not the same as the causes of changes in incidence rates of incarceration (3). This is true of any individual-level intervention for a population (social) phenomenon. Furthermore, research has shown that incarceration rates for people with mental illness have remained relatively stable (4). So why obtain better prevalence estimates of mental illness in prisons?

Researchers should not abandon basic descriptive statistics on carceral institutions for at least three reasons. Such data document the differential consequences of social policy for marginalized groups, form the foundation for understanding how people move through institutions and systems within evolving policy contexts, and quantitatively inform what are ultimately qualitative decisions about triaging inadequate resources.

Regarding documentation of differential consequences, an analogy is instructive: we document racial disparities in incarceration rates because we believe institutional racism in corrections policy is wrong. The question of intervention is secondary. Likewise, we document overrepresentation of people with mental illness in prison as another metric of justice in the justice system.

Regarding the flow of people through systems, most of the U.S. corrections population has resided in the community for decades. Draine and Muñoz-Laboy may be thinking wishfully about recent declines in prison incarceration rates relative to community corrections—small blips on the charts of mass incarceration and mass corrections supervision. And while jail and prison populations are shrinking in some jurisdictions, the prevalence of mental illness may not be. At Rikers Island, for example, the average daily population dropped 12% from 2005 to 2012, but the prevalence of mental illness rose 32%, due in part to limited community-based options (unpublished data, Council of State Governments Justice Center, 2013). Jail and prison statistics tell us when action in the community is failing.

From a systems perspective, it seems self-evident that policy and programmatic reforms will suffer if these efforts do not track the number of people with mental illness encountered by law enforcement, cycling through courts, awaiting adjudication in jails, entering prisons, being supervised in the community, and returning to jail or prison. Ignoring one component of this complex and dynamic process is at the peril of any preferred focal point. Furthermore, discounting rates of mental illnesses in corrections facilities neglects the pathogenic consequences of incarceration itself (5).

Regarding quantitatively informing decision about resources, justice-involved individuals have numerous needs, and with zero-sum public services, data can only inform, not determine, value-laden and political decisions about priorities. Researchers must be clear about which questions their research addresses. Questions about reducing mass incarceration rates have different answers than questions about reducing recidivism. But if the question is what people with mental illness need for a humane and marginally just experience in the justice system, then surely one answer is attention to mental health—and not merely criminal justice—outcomes.