Tuskegee Syphilis Study

Summary

From 1932 to 1972, the United States Public Health Service studied roughly 600 Black men in Macon County, Alabama — 399 with latent syphilis and 201 without — without informing the infected men of their diagnosis, and without offering them effective treatment even after penicillin became the standard cure in the late 1940s, in order to observe the untreated progression of the disease until death.

What Happened

In 1932, the U.S. Public Health Service, working with the Tuskegee Institute, began the “Tuskegee Study of Untreated Syphilis in the Negro Male” in Macon County, Alabama. Researchers enrolled 399 Black men with latent syphilis and 201 without the disease as a comparison group, telling participants they were being treated for “bad blood,” a local term covering various ailments, and offering incentives including free meals, medical exams and burial insurance^[4]. Rather than treating the men’s syphilis, researchers withheld diagnosis and treatment in order to study the disease’s untreated, long-term progression, including through autopsy after death. When penicillin became the standard, effective cure for syphilis in the late 1940s, researchers actively continued withholding it from study participants — including, in documented instances, steering some men away from treatment offered elsewhere — so that the study could continue^[4]. The study ran for 40 years, ending only in 1972 after Public Health Service employee Peter Buxtun’s internal objections were repeatedly rejected and he brought the story to the press, resulting in Associated Press reporter Jean Heller’s exposé^[1].

Who Was Affected

The 600 enrolled men, nearly all poor Black sharecroppers and laborers in rural Alabama, were directly affected; researchers’ own later accounting documented that wives of infected men and children born to them also contracted syphilis as a result of the men remaining untreated and infectious^[5].

Who Was Responsible

The study was designed and conducted by U.S. Public Health Service physicians and researchers (see U.S. Public Health Service), with cooperation from the Tuskegee Institute and local health officials in Macon County. Successive generations of Public Health Service staff maintained the study across four decades and multiple changes in medical standards, including the introduction of penicillin, despite internal objections raised over the years, notably by Peter Buxtun beginning in 1966.

The Justification

Researchers justified the study, in internal reports and publications, as valuable scientific research into the natural history of untreated syphilis, a disease about which detailed long-term progression data was, they argued, otherwise unavailable. This justification did not address, and the study never obtained, informed consent from participants for withholding treatment — a step not legally mandated in U.S. research at the time, but one the study’s own physicians increasingly could not justify to outside reviewers once it became public^[2].

Ideas Behind the File

The study is documented by historians, including James Jones and Susan Reverby, as reflecting scientific racism embedded in early-to-mid-20th-century American medicine — including then-common, since-discredited beliefs among some researchers that syphilis progressed differently in Black versus white patients, a hypothesis the study was partly designed to test using human subjects who were never informed of their diagnosis or the study’s actual purpose^[4].

Institutions

The U.S. Public Health Service directed and staffed the study for its full 40-year duration; the Tuskegee Institute and local Macon County health authorities provided facilities and cooperation.

What Is Certain

That participants were not informed of their syphilis diagnosis, were not offered effective treatment even after penicillin became standard, and that the study continued for 40 years despite this, are all established beyond dispute by the U.S. government’s own 1973 advisory panel investigation and the Public Health Service’s internal study records^[2].

Human Consequences

Participants suffered the untreated progression of a serious, ultimately fatal disease, including neurological and cardiovascular complications; wives and children of participants were infected; and the study’s exposure became a lasting source of documented distrust of the U.S. medical research establishment among Black Americans, a legacy public-health researchers continue to study in relation to later health-engagement disparities.

Accountability

A 1973 class-action lawsuit, supported by the NAACP, resulted in a $10 million settlement and a commitment of lifetime medical and burial benefits for surviving participants and, later, affected wives and children, administered through the Tuskegee Health Benefit Program. President Bill Clinton issued a formal U.S. government apology in 1997, hosting surviving participants at the White House.

What Changed Afterward

The study’s exposure directly led to the National Research Act of 1974 and the creation of Institutional Review Boards to oversee federally funded human-subjects research, and to the 1979 Belmont Report, which established the modern U.S. ethical framework of respect for persons, beneficence and justice that continues to govern biomedical and behavioral research today^[3].

Sources & Evidence

Last reviewed: January 15, 2025. Found an error? See our corrections policy.