In the 1930s, the United States was ravaged by syphilis. This sexually transmitted infection afflicted nearly 1 in 10 Americans, producing painful sores and rashes  that persisted for roughly two years. After these initial symptoms, late-stage syphilis was known to cause organ damage, heart and brain disorders, and even blindness. It was incredibly difficult  to slow the disease’s spread. Experts cautioned against unprotected sex, but the infection could also be passed during childbirth. Worse still, existing treatments like mercury and bismuth were considered unreliable at best and potentially harmful at worst. Today these heavy metals  are classified as toxic, but at the time, doctors were still  uncovering their dangerous side effects. Amidst the uncertainty, health care  professionals had two key questions. Did late-stage syphilis warrant  the risks of existing treatments? And, did the infected individual’s race change how the disease progressed? Many physicians were convinced syphilis affected the neurological systems of white patients and the cardiovascular systems of Black patients. There was little evidence for this theory, but the U.S. Public Health Service  was determined to investigate further. In 1932 they launched a massive experiment in Tuskegee, Alabama. The town had already possessed a small hospital, and the area was home to a large population of potential participants. The PHS collaborated  with local doctors and nurses to recruit roughly 400 Black men presumed  to have noncontagious late-stage syphilis, as well as 200 non-syphilitic Black men  for their control group. But their recruitment plan centered on a lie. While the researchers planned to observe  how syphilis would progress with minimal treatment, participants were told they would receive  free drugs and care for their condition. At first, researchers gave the men existing treatments, but these were soon replaced with placebos. Under the false pretense of providing a special remedy, researchers performed painful and invasive spinal taps to investigate the disease’s  neurological consequences. When patients died, the PHS would swoop in to study the body by funding funerals in exchange for autopsies. In their published studies, they listed  the men as volunteers to obscure the circumstances under which they’d been recruited. Outside Alabama, syphilis treatment  was advancing. A decade after the study began, clinical trials confirmed that penicillin  effectively cured the disease in its early stages. But in Tuskegee, researchers were determined to keep pursuing what they considered vital research. They had yet to confirm their theories about racial difference, and they believed they would never have another opportunity to observe the long-term effects  of untreated syphilis. The study’s leadership decided to withhold knowledge of new treatments from their subjects. During World War II, researchers convinced the local draft board to exempt men from their study, preventing them from enlisting  and potentially accessing penicillin. The study even continued through the 1950s when penicillin was shown to help manage late-stage syphilis. By today’s bioethical standards, withholding treatment in a research study  without a patient’s informed consent is morally abhorrent. But for a large part of the 20th century, this practice was not uncommon. In the 1940s, US led studies  in Guatemala infected numerous prisoners, sex workers, soldiers, and mental health patients with sexually transmitted infections  to study potential treatments. And other studies throughout  the 50s and 60s saw doctors secretly infecting patients with viral hepatitis or even cancer cells. Eventually, researchers began objecting  to these unjust experiments. In the late 1960s, an STI contact tracer  named Peter Buxtun convinced the PHS to consider  ending the study. But after leadership decided against it,  Buxtun sent his concerns to the press. In July of 1972, an exposé of the Tuskegee study made headlines across the country. Following public outcry, a federal investigation, and a lawsuit, the study was finally shut down in 1972— 40 years after it began and 30 after a treatment  for syphilis had been found. No evidence of any racial difference was discovered. When the study ended, only 74  of the original 600 men were alive. 40 of their wives and 19 of their children had contracted syphilis, presumably from their husbands and fathers. In the wake of this tragedy,  and concerns about similar experiments, Congress passed new regulations  for ethical research and informed consent. But systemic racism continues to permeate medical care and research throughout the US. To truly address these issues, the need for structural change,  better access to care, and transparency in research  remains urgent.