The C.D.C. was recently in the spotlight when Mr. Azar said he believed the agency should resume research on gun violence, which it drastically cut more than 20 years ago. Dr. Redfield’s views on gun violence research and other contentious issues such as access to abortion and sexual health education are not yet known.

His work in AIDS research and policy has generated concern over the years, in particular for his call in the mid-1980s to late 1980s for widespread AIDS testing and screening of military recruits for H.I.V.

While pushing for broader AIDS testing during routine exams as a means to contain the epidemic, Dr. Redfield also called for reducing the stigma associated with the disease. At a congressional hearing in August 1987, Dr. Redfield recommended regular testing, at doctor’s appointments and hospitalizations, as well as for marriage license applicants, and incorporating the test into the practice of medicine, according to news reports. But he also said, “We have to tell people it’s anti-American to discriminate against people who have the AIDS virus.”

In the early 1990s, Dr. Redfield was the subject of a military investigation after colleagues suspected that he overstated the therapeutic effects of an experimental AIDS vaccine at presentations and in a report. The investigation led to a correction in some published data, according to documents.

Several high-level colleagues, however, felt the military should have been tougher on Dr. Redfield, who they felt raised false hopes about the efficacy of a treatment vaccine he was developing. At the time, Public Citizen’s Health Research Group sued to gain the records, and made them public.

In a 1992 letter to Col. Donald Burke, the director of the division of retrovirology, Major Craig W. Hendrix, director of the Air Force HIV program, wrote that the credibility of the military’s efforts on retroviral research was at risk and under scrutiny. “Severe, painful steps must be taken less we dishonor the honest labors of so many colleagues and patients within our research consortium. We cannot continue to deceive.”

In an interview Tuesday, Dr. Hendrix, now a professor at Johns Hopkins University School of Medicine, recalled the incident, which he now uses as a case study in ethics.