Mar-a-Lago, President Trump's private club and winter White House in Palm Beach, Fla., is a casual place. And so, it seems, are any official records of those who visits him there.

There "is no system for keeping track of presidential visitors at Mar-a-Lago, as there is at the White House complex," Special Agent Kim Campbell said in a legal filing. She said the Secret Service conducted a lengthy search, only to find "there is no grouping, listing, or set of records that would reflect presidential visitors at Mar-a-Lago."

That is hard to believe, said Noah Bookbinder, executive director of Citizens for Responsibility and Ethics in Washington, which is suing for the records.

Minus any records of presidential visitors, Bookbinder said, "it suggests Mar-a-Lago members and their guests could have access without any sort of vetting or accountability."

The club doubled its membership initiation fee this year to $200,000.

Campbell said the latest search turned up a "few scattered pieces of Mar-a-Lago presidential visitor information found in paper or electronic documents."

Government lawyers filed her statement Wednesday in response to a Freedom of Information Act lawsuit, filed by CREW, the National Security Archive and the Knight First Amendment Institute at Columbia University.

The lawsuit so far has produced just 22 names — members of Japanese Prime Minister Shinzo Abe's traveling party on his official visit in February.

Then-President Barack Obama began routinely releasing White House visitor logs in 2009, after CREW sued. Obama set exceptions for national security or a "necessarily confidential nature," like meeting with nominees.

Trump stopped the White House disclosures. Administration lawyers argue that records on presidential visitors should be broadly exempt from the Freedom of Information Act.

In the Mar-a-Lago case, Bookbinder said, "It appears they're saying they found stuff, but these things are not covered by FOIA."

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