Facebook's (FB  ) Oversight Board claims that the company "has not been fully forthcoming" regarding the whitelisting of high-profile accounts on the platform. According to the board's report, the so-called "cross-check" of celebrity users results in some users being virtually immune from any enforcement of company policies.

"The fact that Facebook provided such an ambiguous, undetailed response to a call for greater transparency is not acceptable," the report reads. "Facebook's answer provides no meaningful transparency on the criteria for accounts or pages being selected for inclusion in cross-check."

In the past, Facebook has said the cross-check program only applies to "a small number of decisions" but has since admitted that description isn't accurate. According to the board, the program includes nearly 6 million Facebook users. Whitelisted users reportedly include everyone from Elizabeth Warren and Candace Owens to Doug the Pug.

"Facebook noted that for teams operating at the scale of millions of content decisions a day, the numbers involved with cross-check seem relatively small, but recognized its phrasing could come across as misleading," the board's report said.

The cross-check program was initiated as a "quality control measure", according to reporting from the Wall Street Journal. The board's report states that Facebook hasn't done enough to explain the practice to users, contributing to the appearance of favoritism or bias.

"The amount of information that is publicly available about cross-check is too limited," Thomas Hughes, director of the Oversight Board, told NPR. "Users need to know what is being done and when and why. If it's all being done in an opaque, unseen manner, it fuels the belief that something untoward is happening."

The board is calling on Facebook to publicly explain why users are included in the cross-check program.

The board was created and funded by Facebook through an independent trust. Members include experts from around the world. While it has the authority to issue binding rulings against the company, it has no authority to change company policies. As a part of its judgment on the cross-check program, the board is expected to suggest changes to the system.

The Oversight Board is relatively new. Its first decision had to do with the company's ban of former President Donald Trump. When asked what rules apply to Trump's content, the company referenced but failed to explain the cross-check program.

During that judgment process, the company refused to answer the board's questions regarding "whether the company had been contacted by political officeholders or their staff about the suspension of Mr. Trump's accounts", according to the recent report.

The company's refusal highlights the board's vulnerable position, proving that the board's power is contingent upon the company's cooperation.

"The credibility of the Oversight Board, our working relationship with Facebook, and our ability to render sound judgments on cases all depend on being able to trust that information provided to us by Facebook is accurate, comprehensive, and paints a full picture of the topic at hand," the report states.

The company has reportedly agreed to give the board more information about the cross-check system and how it works. The board stated that its future decisions would analyze Facebook's fulfillment of its responsibility to share accurate and complete information.