For the first two centuries of U.S. history, outgoing presidents simply took their documents with them when they left the White House. The materials were considered their personal property.
But for the past four decades, every presidential document — from notebook doodles to top-secret security plans — is supposed to go directly to the National Archives as the material is considered the property of the American people.
So when former President Donald Trump left office on Jan. 20, 2021, all his records should have traveled from the White House to the National Archives, according to Jason R. Baron, who served as director of litigation at the National Archives for 13 years.
"No president has the right to retain presidential records after he or she leaves office," Baron said. "And so it is an extraordinary circumstance if presidential records are found in a former president's residence or anywhere else under his control."
But some records – both paper and electronic – were being kept at Trump's Mar-a-Lago resort in Palm Beach, Fla. Officials found 15 boxes worth of documents from Trump's property in January.
And on Monday, the FBI collected 11 more sets of documents, including five marked "top secret," three marked "secret" and three labeled "confidential." Those are the three separate levels for classified government documents.
In addition, one set of the top secret documents was labeled "top secret/sensitive compartmented information." That means the material is considered so sensitive that event those with a top secret security clearance wouldn't be able to see it unless they had a need to know.
The warrant that authorized the search said the FBI was investigating a number of possible crimes, including violations of the Espionage Act. Trump has not been charged with any crime and denies any wrongdoing.
Why can't presidents keep their documents these days?
The rules changed for one reason: Watergate.
When President Nixon resigned amid the 1974 scandal, he wanted to take his documents to his home in California — including his infamous tape recordings.
Congress realized it would not have access to that material, and they also feared it could be destroyed. So legislators passed the Presidential Recordings and Materials Preservation Act, which made all of Nixon's material public property.
However, that measure applied to Nixon only. In 1978, Congress passed the more sweeping Presidential Records Act that has been the standard ever since.
"Every president, when they leave office, those records that have been created by the president and his staff are presidential records that go to the National Archives," Baron said. "The owner is the American people."
This includes all presidential material, whether it's routine, unclassified notes or top-secret national security documents.
Before these laws, there were really no rules covering presidential records. Presidents just took what they wanted as they were leaving office.
"Early on, presidents like John Adams and Thomas Jefferson were very attuned to their place in history and their legacy," said presidential historian Lindsay Chervinsky, the author of The Cabinet: George Washington and the Creation of an American Institution. "And so they were very thoughtful about maintaining their documents, cataloging their documents, and then, of course, sort of making sure that what remained was what they wanted to remain. So that also includes some erasure."
Also, presidential libraries did not exist until President Franklin Roosevelt opened his in 1941.
Trump's controversies with documents
Throughout his presidency, anecdotes surfaced about Trump's handling of documents. For starters, he did not like to read them, and there were reports that he would sometimes rip them up or even flush them down the toilet.
Trump spoke about, or put on Twitter, sensitive material that was believed to be classified. Such material was also reportedly shared with people who did not have the authorization to read it.
Before Trump, outgoing presidents have been described as fully cooperative with the records process, experts told NPR. Baron said he was only aware of minor episodes, where a former president might be asked to turn over a small gift he had received while in office.
There have been a few cases involving former presidential aides. In one instance, Sandy Berger, who had served as the national security adviser to President Bill Clinton, was accused of smuggling classified documents out of the National Archives in his pants. He was ultimately fined $50,000.