According to the Bureau of Justice Statistics, nearly 44% of jail inmates and 37% of prison inmates in the U.S. have a diagnosed mental illness (BJS.gov). This sobering figure highlights an urgent problem: prisons are now the largest mental health institutions in America.
Prisons weren’t built to be hospitals, yet across the world—and especially in the U.S.—they now hold more individuals with mental illnesses than any mental health institution. The justice system, overwhelmed and under-resourced, has unintentionally created a cycle of incarceration and neglect. Once inside, inmates with mental illness often receive inadequate or inappropriate care, and many deteriorate further.
According to a 2021 report by the Treatment Advocacy Center, more than 356,000 individuals with severe mental illness are incarcerated in jails and prisons, compared to only 35,000 who are in state psychiatric hospitals.
Why Are So Many Inmates Mentally Ill?
To answer this, we’ve got to peel back the layers of the criminal justice onion.
1. Deinstitutionalization
In the 1960s and 70s, state psychiatric hospitals across the U.S. were closed in a wave of deinstitutionalization. While the intention was noble—treat people in the community rather than in institutions—the promised community mental health systems were never fully funded.
Result? People with serious mental illness were left without support, leading to homelessness, addiction, and eventually jail time.
2. Criminalization of Mental Illness
Instead of treatment, many individuals are arrested for minor infractions like loitering, trespassing, or disturbing the peace. These are symptoms of untreated mental illness, not crimes.
3. Lack of Access to Care
In low-income communities, mental health services are scarce. Wait times can stretch for months, and insurance coverage is spotty at best. That means problems escalate—and often end in an arrest.
Most Common Mental Illnesses in Prisons
Mental illnesses vary in severity, but here are the top 6 conditions affecting inmates:
- Major Depressive Disorder
- Schizophrenia and Psychotic Disorders
- Bipolar Disorder
- Post-Traumatic Stress Disorder (PTSD)
- Borderline Personality Disorder (BPD)
- Substance Use Disorders (co-occurring with other conditions)
Each of these conditions, if left untreated, increases the risk of violence (to self or others), disciplinary infractions, and repeat incarceration.
How to Improve Mental Health in Prisons?
Improving mental health care in prisons isn’t just a moral responsibility—it’s a practical necessity. Here’s how it can be done:
🔹 1. Early and Thorough Screening
- Conduct comprehensive mental health evaluations during intake.
- Use evidence-based tools to identify signs of PTSD, depression, schizophrenia, bipolar disorder, etc.
🔹 2. Increase Qualified Mental Health Staff
- Hire licensed psychologists, counselors, and psychiatric nurses.
- Ensure that therapists are available on-site, not just visiting periodically.
🔹 3. Develop Specialized Treatment Units
- Create separate wings or pods for inmates with mental illnesses where care is the focus—not punishment.
- Example: Cook County Jail in Chicago has a special mental health ward staffed with professionals.
🔹 4. Train Correctional Officers
- Train all staff in mental health first aid, trauma-informed care, and de-escalation techniques.
- Officers should know the difference between non-compliance and symptoms of a disorder.
🔹 5. End Solitary Confinement for the Mentally Ill
- Solitary confinement often worsens mental illness.
- Replace it with therapeutic alternatives, such as calming rooms or temporary observation units.
🔹 6. Offer Regular Therapy and Counseling
- Provide individual therapy, group therapy, and substance abuse treatment.
- Use evidence-based practices like CBT (Cognitive Behavioral Therapy) and DBT (Dialectical Behavior Therapy).
🔹 7. Create Reentry Support Programs
- Mental illness doesn’t stop at the prison gate.
- Offer post-release care plans, help with housing, job placement, and continued mental health services to reduce recidivism.
Where Do Mentally Ill Prisoners Go?
The destination of mentally ill prisoners varies depending on severity, the facility, and state laws.

Here’s What Usually Happens:
- General Population
Most inmates with mental illness remain in general population, even if they struggle to adapt. This is common when facilities lack designated mental health units. - Mental Health Units Within Prisons
Some larger prisons have dedicated mental health units, where treatment is available, and inmates are separated from the general population for safety and therapeutic reasons. - Segregation or Solitary Confinement
When symptoms lead to behavioral issues, mentally ill inmates are often sent to segregation, even if it’s harmful to their condition. This is a controversial and dangerous practice. - State Psychiatric Hospitals (in rare cases)
If an inmate is found incompetent to stand trial or is gravely disabled, a judge may order a transfer to a forensic psychiatric facility. However, waitlists can be months long, and beds are limited. - Diversion Programs (Alternative)
In some counties or states, inmates with mental illness may be diverted from jail entirely, going instead to a treatment facility through mental health courts or pre-booking diversion programs.
More Opportunities: Hardship Grants for Felons
Life Inside: What Happens When Mental Illness Goes Untreated?
It’s not just hard. It’s brutal. Here’s what inmates with untreated mental illness often face:
- Solitary confinement used as punishment for “bad behavior” that’s actually symptomatic (like talking to oneself or refusing orders).
- Physical abuse from staff or other inmates.
- Self-harm or suicide, due to hopelessness, hallucinations, or trauma.
- Loss of parole opportunities, since behavioral infractions impact eligibility.111111111111`
“The hole made me crazier. I was in there for 23 hours a day. My mind broke.” — Former inmate with schizophrenia, anonymous testimonial via The Marshall Project.
Prison vs. Psychiatric Hospital: A Costly Mistake
You might think locking someone up is cheaper than long-term treatment. But that’s a myth.
- Prisons cost the U.S. $80 billion per year.
- Inmates with mental illness cost more—up to 3x as much due to medical needs, staff interventions, and frequent hospitalizations.
- Jail stays are longer, especially for those who can’t understand the legal process due to mental illness.
Compare that to early intervention and outpatient therapy, which costs a fraction—and leads to better outcomes.
The Impact on Staff
Correctional officers aren’t trained as mental health workers, yet they’re on the front lines.
- High burnout rates and secondary trauma are common.
- Staff are 10 times more likely to suffer PTSD than the general public.
- Many officers admit to feeling helpless or resentful, which impacts how they treat inmates.
Solutions That Work: Programs and Reforms
Some models do work—but they’re few and far between.
1. Mental Health Courts
Divert individuals into treatment, not prison.
2. Crisis Intervention Teams (CIT)
Train police officers to de-escalate mental health crises without violence or arrest.
3. Jail-Based Treatment Units
Facilities like Rikers Island and Cook County Jail have developed specialized units for inmates with serious mental illness.
4. Peer Support Programs
Inmates help each other through structured mentorship, reducing violence and relapse.
Policy Recommendations
We’re not just pointing out problems—we’ve got to push for change.
- Ban solitary confinement for inmates with serious mental illness.
- Fully fund community mental health centers.
- Provide mandatory mental health screenings during intake.
- Train prison staff on trauma-informed care and de-escalation.
- Expand Medicaid and insurance access post-release.
What We Must Do Now
This isn’t just a prison problem—it’s a public health and human rights issue. Ignoring mental illness behind bars costs more money, ruins more lives, and feeds mass incarceration. We can—and must—do better.
Invest in people, not punishment. Treat mental illness with care, not cuffs.
FAQs
What percentage of prisoners have mental illness?
About 37% of prison inmates and 44% of jail inmates have a diagnosed mental health condition.
Can inmates get therapy in prison?
It depends on the facility. In many prisons, only 1 in 3 inmates with a diagnosed mental illness receive treatment.
What is being done to improve mental health care in prisons?
Some states have launched diversion programs, mental health courts, and in-jail therapy units, but systemic reform is still lacking.