A liberal veterans group is suing to block the influence of three outside advisers who have been secretly influencing the Department of Veterans Affairs from Mar-a-Lago, President Donald Trump’s private club in Palm Beach, Florida.

ProPublica reported last week that the advisers — Marvel Entertainment chairman Ike Perlmutter, West Palm Beach doctor Bruce Moskowitz and Washington lawyer Marc Sherman — have been shaping VA personnel and policy decisions despite having no official role or relevant expertise.

The trio, sometimes referred to as the “Mar-a-Lago Crowd,” is failing to disclose its activities as required by federal law, according to a lawsuit filed today in federal court in Washington, D.C., by VoteVets, a liberal activist group that says it represents 500,000 supporters.

The Federal Advisory Committee Act, or FACA, is a Watergate-era sunshine law that requires federal agencies to inform the public when they consult outside experts. VoteVets wants a judge to order the Mar-a-Lago Crowd to disclose records of its activities and cease influencing the VA until it complies with the law. The suit also asks that future meetings of the group be opened to public participation and that minutes of its meetings be kept.

“This group has been operating in the dark,” said Will Fischer, VoteVets’ director of government relations. “Our goal in bringing this lawsuit is to bring these activities to light and make sure our members, veterans and military families are able to see what’s going on with our VA and the people directing the activities of our VA.”

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The VA referred questions about the lawsuit to the Justice Department, which didn’t answer a request for comment. In a statement, a spokeswoman for Perlmutter, Sherman and Moskowitz responded: “We have watched with concern as media outlets — including ProPublica — have misrepresented our actions and used selective emails to paint a distorted picture of our efforts to help the VA and America’s veterans.” The statement asserted that none of the group’s “volunteer efforts,” which it characterized as “recommendations” made in response to requests from the VA, were conducted in secret and that the group didn’t attempt to develop policy or influence personnel decisions.

VoteVets is represented by Democracy Forward, an activist group that challenges actions by the Trump administration. The group has brought similar lawsuits against a hunting council at the Interior Department and an infrastructure panel at the departments of Transportation and Commerce. In the latter case, a judge granted initial discovery.

“It looks like what was happening here was a group of people giving collective advice to the VA, which is precisely the kind of case where FACA should apply,” said John Bies, a former deputy assistant attorney general in the Justice Department’s Office of Legal Counsel during the Obama administration. Courts, he added, have deemed similar government committees to be subject to FACA in the past.

FACA claims have been extensively litigated for decades, with occasional successes for plaintiffs. For example, in 1994, a court ordered the Fish and Wildlife Service not to use a scientific report that was prepared without conforming to FACA, and in 2006, a court found that a panel doing an assessment for the Forest Service did amount to an advisory committee under FACA and had to disclose documents. But the two best-known cases brought under the law were ultimately unsuccessful: challenges to first lady Hillary Clinton’s health care task force in 1993 and Vice President Dick Cheney’s energy task force in 2002.

VoteVets’ complaint cites ProPublica’s investigation and documents that the news organization obtained through the Freedom of Information Act to show how Perlmutter, Moskowitz and Sherman met regularly and weighed in on VA decisions from negotiating a contract for electronic health records to outsourcing medical services to private providers.

“Their statement to ProPublica confirms they saw themselves as operating as a group to provide advice and recommendations to the VA,” said Adam Grogg, the lead lawyer on the case. “The publicly available material puts this squarely within the kinds of cases where courts have acknowledged this is a de facto federal advisory committee.”

ProPublica’s reporting also prompted congressional Democrats to open an investigation, call for hearings, request a probe by the VA’s internal watchdog and call on the VA secretary to cut ties with the Mar-a-Lago Crowd.