With new revelations emerging every day about the botched execution of a prisoner in Oklahoma, even those who favor the death penalty (I am a strong opponent) may have some reservations about the way it is carried out. Despite the uproar from both sides, I believe there are some major ethical considerations that have been overlooked in this case.

Setting aside for a moment the American Medical Association (AMA) Code of Ethics, which states that “a physician … should not be a participant in a legally authorized execution,” we can explore those concerns.

The first is the prohibition of “cruel and unusual punishment” in the Eighth Amendment to the U.S. Constitution. Although there would have to be a determination by the courts that the constitutional right of Clayton D. Lockett, the Oklahoma prisoner, was violated, it’s a matter of common sense that an action that results in a person “writhing and moaning in agony” (as described in a New York Times editorial) constitutes cruelty. The reason lethal injections were adopted in the first place is that they were seen as more humane than hanging or firing squads. Administering the death penalty in a way that causes demonstrable harm may not meet a legal test of “cruel and unusual punishment,” but it certainly violates the prohibition of cruel and unusual punishment from an ethical point of view.

A second consideration has not been mentioned so far in the news accounts of the Oklahoma case that I have read. That is the question of whether the three-drug combination for the lethal injection prepared by compounding pharmacies amounts to experimentation on prisoners.

Federal regulations strictly limit such experimentation.

The type of research that is permitted must be on conditions particularly affecting prisoners as a class, or “research on practices, both innovative and accepted, which have the intent and reasonable probability of improving the health or well-being of the subject.”

The Times editorial describes the contents of the injection as an “untested combination” of three drugs and “new formulas” concocted by prison systems. Is this human experimentation on prisoners? It certainly appears to be.

However, several reasons militate against considering these untested drug combinations research. Perhaps the most telling reason is the widely accepted definition of “research”: “a systematic investigation, including research development, testing and evaluation, designed to develop or contribute to generalizable knowledge” (45 CFR 46.102).

Biomedical research today is carried out in accordance with a written protocol, which must be prospectively reviewed and approved by an institutional review board (IRB) comprising medical experts and members unaffiliated with the institution conducting the research. In reviewing the protocol and procedures for conducting the research, the IRB must determine that risks to subjects are minimized. When the research involves experimental drugs, the manufacturers’ brochures are normally provided to the IRB reviewing the research. Nothing in the way prisons obtain these drug combinations fits the picture of human subjects research as defined in the federal regulations (45 CFR part 46, subpart C). As one article says: “Prisons generally keep the identity of the pharmacies a secret, and it is not clear where the compounders get their raw materials.”

So there are two possibilities. Either the administration of lethal injections of untested materials from secret sources is not human subjects research, but simply “prison practice” in administering the death penalty, or it is human subjects research in flagrant violation of existing regulations.

It is likely that experts familiar with the federal regulations governing research would take the former view. But that does not take prison systems like the one in Oklahoma off the moral hook. Even if the use of untested drug combinations obtained from fly-by-night, secret outlets is not research, and even if killing prisoners in this way does not amount to a violation of the Eighth Amendment, it is still a serious ethical violation of humane practices.

The secrecy surrounding the business of lethal injections is remarkable, considering that the practice is carried out by states accountable to their populations. Prisons keep the identity of the pharmacies a secret and the pharmacies do not reveal the sources of their materials. Prisons also keep secret the identities of the physicians involved in the executions. If the revelations in the Oklahoma case are typical, it is not unreasonable to question the actual role and competence of the physicians engaged in this work. And given the AMA’s opposition to physicians’ involvement in executions, it is no wonder they do not want their identities revealed.

Incidents like the botched execution in Oklahoma bring to light information about practices and procedures that are largely unknown. We have no way of knowing how many and what kinds of similar incidents occur in other states that lawfully kill prisoners.

In light of the Oklahoma incident, President Obama has called on the U.S. attorney general to formally review how the death penalty is applied.

Given the stakes, it’s time to lift the veil of secrecy. We need transparency, not a drawn curtain.

Ruth Macklin is a professor, department of epidemiology and population health, Albert Einstein College of Medicine, Bronx, NY. She blogs at The Doctor’s Tablet.