July is Minority Mental Health Month, established to spotlight the flawed diagnosis of mental illness among minorities. Black men, for example, are nearly six times as likely to be given schizophrenia diagnosis as white men. That problem is compounded by minorities, especially African-Americans, often having mental healthcare provided in prison, where the standard of care is so low that lack of treatment has fuelled a suicide epidemic.

States are repeatedly finding themselves in court for this malpractice. Just last month, US District Court Judge Myron Thompson ordered the Alabama Department of Corrections to take immediate steps to improve its mental health services or face a court takeover of the prison system management.

Why is so much mental healthcare provided to African-Americans in prison? First and foremost, because African-Americans are overrepresented in US prisons and jails.

There are also other historical factors that exacerbate the problem. Over the past two centuries, medical and legal professionals mislabelled behaviour such as escaping slavery and advocating for civil rights as a byproduct of psychiatric madness.

Even worse, instead of treating this purported madness, they simply locked patients in facilities with deplorable conditions.

This criminalisation of mental health has strengthened the control of white authorities over African-Americans by simultaneously delegitimising activism and justifying incarceration.

The racial disparities in mental health today have grown from centuries of racism and only by addressing these systemic problems can we adequately provide mental healthcare to minority populations.

Racial disparities in diagnosing conditions such as schizophrenia are sometimes presented as an effect of biology, but they are not. Instead, they are the direct result of racist thinking about African-American psychology that dates to at least the 18th century. Slave owners and their apologist physicians invented psychiatric “disorders” such as “draeptomania” to explain the urge to run away.

In the lead-up to the Civil War, they distorted statistics to argue that freedom would drive the ex-enslaved crazy. They also propagated the idea that African-Americans were more childlike and simplistic, incapable of feeling pain or sorrow, to justify experimentation and exploitation.

After the Civil War, as the South struggled with emancipation and reconstruction, the black psyche was increasingly portrayed as immoral and inherently criminal, justifying both the need for Jim Crow and mass incarceration, in prisons and psychiatric hospitals. Sometimes the line between the two was exceedingly thin, with mental healthcare facilities that functioned more like prisons than places of treatment.

Across the country, but especially in the South during the era of Jim Crow, these hospitals were segregated, with black patients held in separate parts of the institutions or in separate locations entirely. While the Supreme Court’s infamous Plessy v Ferguson decision mandated these facilities be equal to those provided to white patients, in practice, they most certainly were not.

Instead, in many states such as Georgia, Alabama and Mississippi, African-American patients suffered from state-sanctioned confinement and neglect.

In Alabama alone, thousands of people were subjected to decades of substandard housing and nutrition in deathtrap buildings. Hospitals were presided over by white male superintendents who employed unlicensed Cuban refugee doctors, ordered massive amounts of electroshock and chemical “therapies” and put patients to work in the fields as though the hospitals were still plantations. These states were not outliers — they were just the tip of the national iceberg.

In Alabama, these conditions went unchallenged until 1969, when Judge Frank Johnson heard a case brought by civil rights advocates and the federal government after a joint Justice Department and Department of Health, Education and Welfare investigation revealed horrendous conditions and almost no state spending on black patients, including children.

Less than 50 cents per patient per day was allocated for food and clothing. Searcy, the blacks-only hospital in Mobile, had never applied for any federal funds to develop treatment programmes because they did not believe black patients would respond.

Science, however, did not back this claim. Numerous witnesses declared there was no medical justification for segregation and no scientific difference between black and white mental illness. Looking at this evidence, Johnson declared the conditions for African-Americans in Alabama’s mental hospitals unconstitutional and ordered they be fixed.

The state largely avoided enacting such changes, however, and this problem would only be exacerbated because, just as activists were tackling these deplorable conditions, their civil rights activism prompted the psychiatric community to create new justifications for diagnosing mental health issues among African-Americans.

In 1968, the American Psychiatric Association took deliberate steps to change the definition of schizophrenia to include “aggression” where it had previously not. While the APA denied — and has continued to do so — charges that such a definition would target the civil rights activism of black men, the research of historian Jonathan Metzl reveals this claim to be disingenuous. The anger of black men was portrayed as a byproduct of mental illness, rather than a fight against oppression. New drugs intended to target the angry black man were advertised to psychiatrists.

The mislabelling of African-American activism as a pathology and the intertwined history of racism and abuse has had long-lasting consequences. The effort to demonise activism as a mental illness has meant those who are sick may struggle to seek treatment — African-Americans are significantly less likely than white people to trust a psychiatrist. They are also less likely to be covered by insurance that includes mental health services, especially in states such as Alabama that refused to expand Medicaid under the Affordable Care Act. These structural problems often lead to a cycle of lack of care, homelessness and imprisonment.

Rather than receiving treatment for illness, African-Americans end up incarcerated because of its symptoms. As the ongoing Alabama lawsuit demonstrates, the same states that warehoused African-Americans without offering adequate treatment for mental illness more than 50 years ago are still locking people away in the same hideous conditions.

This tendency to incarcerate the mentally ill instead of treating them is not just a Southern problem; it’s a national one. The largest mental health facility in the country is the Los Angeles County Jail. But prisons are not mental healthcare providers, and prison life itself is known to make mental illness worse.

The consequences of a system that overlays race with criminality is a lack of funding for mental health services where people need them and a continued belief that there is something biologically wrong with African-Americans.

We are both overdiagnosing some mental illnesses, such as schizophrenia, and underdiagnosing others, such as depression, mistaking symptoms for criminality that deserves punishment, not treatment.

Instead, we should be making mental health services affordable and accessible and keeping people with mental illness out of prison. We must also be careful not to see mental illness in activism and assertiveness. When we talk about disparities in mental health, we need to look at these systemic issues, and not perpetuate myths about biological difference. The problem in psychiatry is not race — it’s centuries of racism.

• Kylie M. Smith is assistant professor and the Andrew W. Mellon faculty fellow for nursing and the humanities at Emory University. She is the author of the forthcoming Talking Therapy: Knowledge and Power in American Psychiatric Nursing (Rutgers University Press 2019)