(CNN) Ethics experts are crying foul after requests for the public financial disclosures of Acting Attorney General Matthew Whitaker have gone unfulfilled.

In a letter sent to the US Office of Government Ethics Friday, American Oversight, an outside watchdog group, said that the Department of Justice had not produced a copy of Whitaker's public financial disclosure reports, despite regulations requiring them to do so, and asked the ethics agency to investigate.

Whitaker, who served as chief of staff to the former attorney general up until his appointment to the top role earlier this month, would likely have had to file two sets of public financial disclosures since joining the Justice Department last year. According to federal ethics law, agencies must make those reports available to public requestors within 30 days of their filing -- a deadline that would have already passed for Whitaker.

"The idea that they wouldn't release this report promptly is mind-boggling," said Walter Shaub, the former director of the US Office of Government Ethics.

Shaub, a senior adviser to another ethics watchdog group, Citizens for Responsibility and Ethics in Washington, and a CNN contributor, said Monday that his own outside group had also requested Whitaker's financial disclosures nearly two weeks ago, and has been told their request is "processing."

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