Today, about 14.5 percent of men and 31 percent of women in jails have a serious mental illness, such as schizophrenia, major depression, or bipolar disorder, compared to 3.2 and 4.9 percent, respectively, in the general population. While estimates vary, the prevalence of serious mental illnesses is at least two to four times higher among state prisoners than in community populations.
The concentration of drug arrests in urban communities of color is a primary driver of pervasive racial disparities in the criminal justice system. African Americans are significantly more likely to be arrested, 13 times more likely than whites to go to prison for a drug conviction, and represent 62 percent of people imprisoned for a drug conviction, despite negligible differences in reported drug use. Today, nearly 68 percent of people in jail overall and more than 50 percent of those in state prisons have a diagnosable substance use disorder, compared to 9 percent of the general population.
Despite this high need, less than 15 percent of people who are incarcerated receive appropriate treatment.
From the Vera Institute.