Public-facing documents scrubbed from the White House's website shortly after President Donald Trump was inaugurated — including White House visitors' logs, waivers of ethics regulations and a host of other records — still haven't been replaced, fueling advocates' concerns about the new administration's transparency.

During the first week of February, 31 databases — reporting legally mandated White House payroll reports to Congress, budget documents, White House visitor records and public response documents — were removed from the White House Open Data portal, the platform created to disclose information about 1600 Pennsylvania Avenue and its operations.

Visitors to the site on Jan. 28 found this (see screenshot here).

Visitors to the site on Wednesday found this (see screenshot here).

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The previous presence of the documents was confirmed through publicly available archived versions. Some of the data, preserved by the National Archives and Records Administration, are also available on the White House website of former President Barack Obama.

The White House didn't return requests for comment.

"From the perspective of anyone who thinks that the greatest opportunity afforded by modern technology is for the government to inform people directly, not just simply through the lens of the press — that's something this administration has talked a lot about — that's leaving a lot of informed public opportunity on the table," said Alex Howard, deputy director of the Sunlight Foundation, a nonpartisan nonprofit that advocates for government transparency.

It's likely that some of the documents simply aren't available yet, Howard said.

Based on timing of data releases by the Obama administration, White House visitors' logs likely won't be available until mid-April, he said. However, because no law requires that such logs be made public, their release isn't guaranteed.

The logs can show who, exactly, is speaking with the president and other administration officials. While certain groups can be excluded — a potential Supreme Court nominee, say, or someone whose life might be placed at risk by identification — they have repeatedly cast light on lobbying activities within the White House.

But "to date, the transparency that the administration has shown around who's visiting and talking to the president has principally revolved around someone taking pictures of him sitting at the Oval Office desk with people around him, who may or may not be identified in the picture," Howard said. "They certainly are not being identified in any kind of structured and systematic disclosures from the White House."

Viveca Novak, editorial and communications director for the Center for Responsive Politics, which tracks lobbying on elections and policy, said that information should be published.

"If people go to the White House and know that their names are not going to be disclosed, it may indeed affect who goes to the White House and who tries to influence the president or the president's staff," Novak said.

"We're talking about a new health care policy. We're talking about changes in the tax code that are going to mean millions of dollars for some companies," she said. "If these companies, if these groups, are sending representatives to the White House — similar to them sending representatives up to Congress to talk to members of Congress — I think the public should know that."

@ErinCRichey: Take note: All White House Open Data catalogs removed from website

Regardless of how the White House feels about disclosure, it may be the path of least resistance in certain cases, Howard said. The visitors' logs, specifically, are created by the Secret Service — which, unlike the White House, is a separate agency subject to the Freedom of Information Act.

The Secret Service has been sued repeatedly over the visitors' logs, both winning and losing at times. The Obama administration eventually opted to release visitors' logs voluntarily to prevent parts of the Executive Office of the President from being subject to the FOIA.

Still, Howard isn't ruling anything out.

"This is a choice an administration makes," he said. "If they choose not to [release visitors' logs], then public interest organizations and advocates, including Sunlight, will have to make a decision about whether we want to sue the Secret Service."

@frick: From 30+ datasets to 0. "Thanks" @realDonaldTrump. Open Data | The White House

Pages for other disclosures on the White House website remain blank — including one reporting waivers of ethics regulations to allow executive branch appointees to serve without being bound by all or a part of an executive order enacted on Jan. 28 that restricts the lobbying activities of former government officials.

As the executive order doesn't require that waivers be disclosed to the public, it's unclear whether Trump or his designees have provided any waivers. A similar executive order that Obama signed also didn't require public disclosure, but his administration chose to post them online anyway.

Former President Bill Clinton's version, which Trump's most closely resembles, required that waivers be published in the Federal Register.

Like the visitors' logs, the waivers were something of an issue during Obama's years in office. In 2009, Sen. Chuck Grassley, R-Iowa, called on Robert Cusick, then the director of the Office of Government Ethics, to gather and release all ethics waivers and recusals granted by the Obama administration.

"The American people deserve a full accounting to better understand who is running the government and whether the administration is adhering to its promise to be open, transparent, and accountable," Grassley said in a statement at the time. "I'm not asking for anything the director of the Office of Government Ethics doesn't already have the legal authority to do."