Publisher’s Note: Good to see university professors speaking out in the Wall Street Journal about these gross violations of the Nuremberg Code. College students are not guinea pigs. Vermonters! If you haven’t signed the Vermonters for Health Choice petition to preserve Informed Consent and Health Freedom, now would be a good time.

Some 450 U.S. colleges and universities—including our institutions—have announced policies mandating that all students be fully vaccinated against Covid-19 before the fall semester, with some requiring vaccination now for the summer term. Schools have for decades required vaccination against infectious diseases, but these mandates are unprecedented—and unethical. Never before have colleges insisted that students or employees receive an experimental vaccine as a condition of attendance or employment.

Even soldiers, whose rights are constrained when they join the service, aren’t being compelled to take a Covid vaccine. In a case involving a vaccine against anthrax, a federal district judge held in 2004 that “the United States cannot demand that members of the armed forces also serve as guinea pigs for experimental drugs” absent informed consent or a presidential waiver of service members’ legal protections. The following year the judge held that an emergency-use authorization from the Food and Drug Administration was insufficient to meet the legal test.

The FDA has issued such authorizations for three Covid vaccines, but it hasn’t fully approved any of them. Students at Notre Dame (for example) resume classes on Aug. 23, and freshmen arrive on campus Aug. 18. The Pfizer vaccine—first in line for approval—requires three weeks before the booster shot, so it would have to be approved by July 28 for students to meet the school’s deadline without making themselves experimental subjects. Pfizer applied to the FDA May 7 for “priority review,” a process that usually takes six months.

Universities might counter that—as with elementary schools requiring pediatric vaccinations—immunization is for students’ own good. But children can be at significant medical risks from the illnesses that we vaccinate them against, particularly when community vaccination rates are low. Not so with Covid. For those under 30, the risks of serious morbidity and mortality are close to zero. By contrast, early indications from passive surveillance systems (which call for follow-up investigation) and a June 10 review by the FDA’s Vaccines and Related Biological Products Advisory Committee indicated an excess risk for heart inflammation, especially in men 30 and younger.

Colleges’ vaccine mandates also ignore the huge number of students—thousands of them at Notre Dame—who have already recovered from Covid infection, and who thus possess natural immunity, which studies have suggested is more robust and durable than vaccine immunity. While vaccinating Covid-recovered patients might produce an antibody uptick, there is no epidemiological evidence that this improves relevant clinical outcomes like reinfection or transmissibility. Previous infection can easily be verified with the university’s own records of testing throughout the past school year, a positive viral test from another provider or an antibody test, which would prove either natural immunity or vaccination.

Forced vaccinations would also commandeer populations that were deliberately excluded from clinical trials, thus subjecting them to novel experimental risks. This includes not only patients who’ve recovered from Covid, but pregnant and breast-feeding women as well.

These coercive mandates violate basic principles of medical ethics. Even if the vaccines receive full FDA approval, no sensible understanding of herd immunity can justify forcing vaccinations on healthy young adults who are at minimal risk of hospitalization or death from Covid, especially those who already had Covid. We don’t immunize children against diseases that primarily harm the elderly in hope of reducing transmission risks for the elderly. That would use the recipients as a means to another end, which is unethical.

Consider the analogy of nontherapeutic research, from which the research subject doesn’t stand to benefit directly. The central canon of medical ethics in this situation is the free and informed consent of the research subject, as articulated in the Nuremberg Code and the Helsinki Declaration. Informed consent is likewise required for medical decisions in all adults of sound mind. This is arguably the most deeply rooted doctrine in contemporary medical ethics.

A person may freely choose to accept medical risks for the benefit of others, as when one donates a kidney for transplant. But there is no moral duty to do so. This is why we don’t harvest organs without consent, even if doing so would save many lives. Those who make such sacrifices for others must truly be volunteers, not conscripts drafted by college administrators.

University leaders might claim that vaccine mandates are necessary to make faculty, staff and students “feel safe” enough to reopen. That’s specious. Requiring the naturally immune to be vaccinated doesn’t make anyone actually safer. It is wrong to risk harming healthy people so that college can peddle a psychological placebo to those who don’t care enough to consider basic scientific facts.

We must maintain our integrity under pressure. It is precisely in dire situations, such as wars or pandemics, that we are most sorely tempted to abandon ethical principles. Authorities rushing to implement mandatory vaccination protocols are ignoring available scientific data, basic principles of immunology and elementary norms. Even if some sincerely think that these regimes are needed to open safely, that belief neither makes it so nor justifies coercive policies that steamroll fundamental liberties.

Dr. Kheriaty is a professor of psychiatry and director of the Medical Ethics Program at the University of California, Irvine. Mr. Bradley is a law professor at Notre Dame.