People with mental health disorders are overrepresented in the justice system, and incarceration can make their symptoms worse. According to the American Psychological Association, 45–64% of incarcerated people have reported mental health concerns, and the World Health Organization says that mental health problems are up to seven times more likely to occur in prisons than in the general public.

Incarceration can have both acute and long-term mental health impacts. For example, incarceration can lead to depression and bipolar disorder, and solitary confinement can be especially harmful for people with severe mental illness. The physical environment of prison can also be stressful, with concrete walls, little natural light, and a lack of stimulation. These factors can lead to boredom, which can be stressful in itself, and frequent staff shortages can mean people don’t get out of their cells as often.

Incarceration can also make it difficult for people to get appropriate treatment for their mental health. According to the Prison Policy Initiative, 66% of people in federal prisons and 74% in state prisons reported not receiving any mental health care while incarcerated.