The Tuskegee Syphilis Study (1932-1972)

For 40 years, the US Public Health Service studied the progression of untreated syphilis in 399 Black men in Alabama — without informed consent and without providing treatment even after penicillin became the standard cure in 1947. The men were told they were receiving free healthcare. The study, exposed in 1972, became the most infamous example of medical racism in American history and directly led to the creation of modern research ethics regulations.