Depending on whom you ask, yesterday’s U.S. government workshop on the state of nonhuman primate research was either a raging success or a complete fiasco. The event, held at the National Institutes of Health (NIH) in Bethesda, Maryland, brought together dozens of scientists, veterinarians, and bioethicists to discuss how research on monkeys and related animals is contributing to human medicine and to review the welfare policies that surround this work. But observers differed widely on whether it accomplished what Congress had in mind when it told NIH to hold the event.

“It was a great showcase of the importance nonhuman primates have played and continue to play in human health,” says Anne Deschamps, a senior science policy analyst at the Federation of American Societies for Experimental Biology in Bethesda, one of several scientific organizations that signed onto a white paper released in advance of the meeting that promoted the use of these animals in biomedical research. She contends that research on these animals has been critical for our understanding of HIV and the human brain.

But the animal rights group People for the Ethical Treatment of Animals (PETA), whose lobbying efforts led to the workshop, says the meeting was supposed to determine whether monkeys and their relatives belong in laboratories in the first place. “It was an infomercial for the use of monkeys in experiments,” says PETA Senior Vice President Kathy Guillermo in Norfolk, Virginia. “It was a wasted opportunity.”

The path to the workshop began in 2014, when PETA blanketed Washington, D.C., with ads alleging that researchers at an NIH lab in Poolesville, Maryland, were subjecting rhesus macaques to cruel experiments by removing them from their mothers at birth and addicting them to alcohol. In response, four members of Congress requested that NIH investigate the lab. In 2015, the agency announced that it had found no major issues, but it decided to phase out the experiments, blaming funding rather than animal rights pressure. At the same time, Congress included language in a 2016 spending bill that asked NIH to “conduct a review of its ethical policies and processes with respect to nonhuman primate research subjects, in consultation with outside experts, to ensure it has appropriate justification for animal research protocols.”

That request became yesterday’s workshop. NIH Director Francis Collins kicked off the proceedings, calling it a “very important day” and stating that nonhuman primates “have proven to be exceptionally valuable in biomedical research.” But he also said that the welfare of these animals—more than 100,000 of which currently reside in U.S. labs—was critical. “We need to respect all of the species that contribute so much to our understanding of human health and disease.”

A series of speakers then extolled the advances made possible by research involving laboratory monkeys. Nancy Haigwood, director of the Oregon National Primate Research Center in Beaverton, said that some of today’s most powerful HIV drugs, including AZT and tenofovir, were first tested in rhesus macaques, and that the animals will play a critical role in fighting emerging infectious diseases such as Zika and Ebola. “Nonhuman primates will be essential to having a rapid response.”

Michael Platt, a neuroscientist at the University of Pennsylvania, said that because macaques live in social groups like we do, researchers can use them to study disorders like autism. His lab has found that giving the “trust hormone” oxytocin to monkeys improves their social interactions. “They basically use the same neural circuits we do,” he said.

Other speakers described their work utilizing monkeys to improve assisted fertility techniques in humans and of stimulating monkey brains with electrodes to study the basis of vision. “Animal models are critical to our scientific understanding of the nervous system,” said William Newsome, a neuroscientist at Stanford University in Palo Alto, California. “Tissue culture does not get depression, Parkinson’s, or Alzheimer’s.”

A discussion session that followed was largely dedicated to how researchers can better share their data and whether they should publicize negative results. Still, Larry Carbone, the interim director of the Institutional Animal Care and Use Program at the University of California, San Francisco, brought up some of the first welfare issues in the workshop by stating that lab primates should be housed in more natural environments—with dirt, big spaces, and large social groups—like those seen in some national primate centers. Some attendees agreed, though others said that labs offered more controlled environments.

Charles Murry, a pathologist at the University of Washington, Seattle, whose lab uses stem cells to repair induced heart damage in macaques, added that scientists need to do a better job of convincing the public of the importance of animal research. “Our press people tell us not to mention the word ‘monkey,’” he said. “We should be doing more than trying to keep a low profile. That’s the path to the extinction of the whole program.”

Ethical issues came more into play in the afternoon. In a session on research oversight, NIH and U.S. Department of Agriculture representatives reiterated that researchers working with nonhuman primates must justify their work and do their best to minimize pain and distress. Other panelists spoke of how to take better care of lab monkeys and how to avoid duplicating research that has already been done.

The only real sparks flew during a follow-up discussion session, when Tom Beauchamp, an ethicist at Georgetown University in Washington, D.C., brought up laboratory chimpanzees. In 2011, a U.S. National Academy of Medicine report found that—for scientific and ethical reasons—most research on chimps was unnecessary, a move that eventually led NIH to end all of its support for invasive chimpanzee research. Similar issues now confront the use of other nonhuman primates, Beauchamp said. “A lot of people here have been saying that scientific necessity is the key issue. … That’s just the first step. There has to be moral justification as well.”

Jeffrey Kahn, a bioethicist at Johns Hopkins University in Baltimore, Maryland, and the chair of the chimpanzee report, added that nonhuman primate research should only be conducted if it has to be conducted. “It’s not ethically acceptable to do research that is not necessary. Being ‘necessary’ is not the same as ‘worth doing.’”

That led to a debate about just what constituted “necessary” and “moral justification.” Even research that doesn’t have an immediate translation to people—like figuring out how the monkey brain works—is necessary, argued Newsome, because it could eventually lead to significant new knowledge that might improve human health. “It will be a tragedy for the world if we don’t leave room for basic science.” Most attendees seemed to agree, with some stating that not doing research on monkeys was ethically indefensible because humans would suffer down the line.

Despite that ethical debate, animal welfare groups said they were upset that science—not welfare—dominated the workshop. Of the 13 speakers, eight make their living working with nonhuman primates. The workshop also only devoted 2 minutes—instead of its scheduled 30 minutes—to public comments. “We are extremely disappointed that no animal protection groups were invited,” wrote Kathleen Conlee, vice president of animal research issues for The Humane Society of the United States in Washington, D.C., in an email to ScienceInsider. “It is clear that NIH has not followed through on what Congress requested, which was to examine ethical policies and processes.”

Allyson Bennett in Madison, a spokesperson for Speaking of Research, an international organization that supports the use of animals in scientific labs, says that there was more discussion of ethics than it appeared on the surface. “Ethical considerations are embedded in institutional review and federal oversight,” she says, noting that no work on nonhuman primates can be funded or take place unless it meets strict welfare guidelines. “The workshop absolutely fulfilled its mandate.” Ethics, she says, go beyond animal welfare. “The public is interested in new knowledge and medical progress. That’s a key piece of the ethical justification for this work.”

Correction, 9 September 2016, 10:06 a.m.: The photo caption originally identified the monkeys as being located in Bastrop, Texas. They were in fact at an NIH lab.