Located among longleaf pine and hardwood trees, low ridges, and broad floodplains, Tuskegee, Alabama, is a small town that’s been a big part of American history. Despite a modest population of less than 10,000 people, Tuskegee has been able to boast many notable residents who have made names for themselves in everything from sports to the arts. Among them have been the Tuskegee Airmen, the first African American Air Force unit, which served during World War II, and Rosa Parks, the icon of the civil rights movement, who sparked the Montgomery bus boycott in 1955.

The Tuskegee syphilis experiment, conducted from 1932 to 1972, examined the natural progression of untreated syphilis in poor, rural black men — without their informed consent.

Tuskegee, though, is also remembered for one of the worst chapters in the history of medical research. Forty years ago, in 1972, newspapers revealed the story of a syphilis study that was callous in its deception of research participants, and damaging, even today, in the distrust it sowed among black Americans. The study had started another 40 years prior, in 1932, when the United States Public Health Service (USPHS) needed to rescue a financially troubled syphilis intervention in Macon County, Alabama. The intervention was first established in partnership with a Chicago-based philanthropic organization, but its future was uncertain when the organization’s funds dried up during the Great Depression.

Syphilis, the sexually transmitted disease caused by the bacterium Treponema pallidum, was the subject of conflicting scientific hypotheses at the time, including the hypothesis that the disease behaved differently in blacks and whites. Interested in testing those hypotheses and faced with disappearing funds for treatment, the USPHS turned its project into a study of untreated syphilis. Also influencing the decision was the fact that the USPHS was discouraged by the low cure rate of the treatments at the time, mercury and bismuth. But by the mid-1940s, penicillin was in use as a proven treatment for syphilis. In spite of that medical advance, the USPHS withheld treatment from a total of 399 infected patients by the time the study ended in 1972.

What made the study especially insidious was its benign beginning, evolving from a partnership with an organization that promoted the health and welfare of black Americans. It thus benefited from the cooperation of black leaders at the Tuskegee Institute, as well as local church leaders, even as it turned into a deceptive study that gave syphilis victims the false impression that they were receiving treatment for their illness. When recruiters for the study announced that locals could receive free medical care, the response was overwhelming. Once recruited, those who had syphilis were told they were being treated for “bad blood,” a colloquial term for a variety of ailments. In truth, they received no proper treatment for their illness, so that investigators could study its progression.

In its beginning stages, syphilis causes sores and rashes around the mouth and pubic region, but left untreated, it can cause more serious complications and even death. Some of the participants in the Tuskegee syphilis study went blind. Others went insane. Estimates of the number who died from untreated syphilis range from 28 to 100.

The person who blew the whistle on the study was Peter Buxtun, an epidemiologist employed by the U.S. Public Health Service. Reflecting on the Tuskegee study years later, he said, “I didn’t want to believe it. This was the Public Health Service. We didn’t do things like that.” A front-page headline on the July 26, 1972, issue of the New York Times announced, “Syphilis Victims in U.S. Study Went Untreated for 40 Years.” On November 16, 1972 — 40 years ago tomorrow — a memorandum from Assistant Secretary of Health Merlin DuVal ordered the termination of the Tuskegee study. (Prior to serving as assistant secretary of health, DuVal was also the founding dean, in 1964, of the University of Arizona College of Medicine.)

In addition to terminating the study, the federal government began paying reparations to the victims and their families. In a presidential apology 25 years later, Bill Clinton admitted that “[t]he United States government did something that was wrong — deeply, profoundly, morally wrong.” In spite of those acts, the legacy of the Tuskegee study persists. Although distrust of the medical establishment existed among blacks long before the study, a common view among researchers and health care providers is that revelations of the study’s unethical practices cemented that distrust. Suspicions about childhood vaccines and AIDS research and treatment, among other resistance to medical care and research, have been attributed to the study’s legacy.

Exactly how much distrust the Tuskegee study has generated has been a topic of debate. Uncertainty lurks in sorting out the study itself from what historian Susan Reverby has called “the myriad other experiences of Black America with health care,” including experiences “lacking labels or formal recognition [that] become part of the reference to ‘Tuskegee.’” Reverby cites “day-to-day encounters by Black Americans in the arena of health care [that] reopen old wounds,” rendering the name Tuskegee a sort of shorthand for various causes of suspicion and unease.

Although ethical guidelines now prevent the kind of research that took place in Tuskegee, problems of unequal treatment linger in the medical establishment. Numerous studies have revealed that black, Latina/Latino, and other minority patients commonly receive a lower quality of service from health care providers compared to their white counterparts. Some of the disparities in the services they receive can be explained by differences in insurance coverage and financial resources, but disparities still exist even after accounting for those factors. Examples of lower quality of service include less aggressive treatment for heart conditions and a lower likelihood of receiving kidney transplants and the drug therapy commonly called the “AIDS cocktail.”

Among other possible causes, time constraints while interacting with patients can drive unequal service, leaving health care providers to fall back on stereotypes about a patient’s interest in self-care and willingness to follow a doctor’s recommendations. The resort to stereotypes can be made worse if the patient, lacking trust in the health care provider, withholds information during a check-up or other visit.

This entanglement with so many other issues and experiences, however, can ensure that the lessons from Tuskegee remain relevant as we confront ongoing problems of inequality in health care. Tuskegee can be the moment we remember to consider how far we’ve come and how far we still have to go. In the same way that the Stonewall riots have started conversations about homophobia and the 1973 Wounded Knee incident has started conversations about the grievances of Native Americans, Tuskegee can help us continue the conversation about health disparities.

The good news is that there are solutions. We can address disparities by ensuring that more minorities enter the health professions and more health professionals practice culturally competent health care. And the simple act of helping people become aware of their unconscious racism in a nonthreatening way can prompt them to act on their egalitarian ideals, regulating their interactions with people from other racial and ethnic groups.