The United States takes its secrets very seriously. There are strict rules governing who can have access to classified material and the locations in which such documents can be viewed or stored.
In a secure part of the Capitol Hill complex in Washington, politicians reviewing secret information go to a specially designed room, known as an SCIF. They leave outside phones and watches and other devices that connect to the internet. Once inside, they can read or be briefed on sensitive information without anyone eavesdropping.
There are similar facilities at the White House, the Pentagon and other defence and intelligence establishments. Some are portable and can be set up quickly if senior figures are on the move.
There are even SCIFs in some universities where research staff can discuss sensitive projects with government officials or defence contractors.
Most members of the public have never seen the inside of such facilities, but the famous photo of Barack Obama, Joe Biden, Hillary Clinton and top officials watching the attack on the compound of Osama bin Laden in 2011 was taken in the secure situation room in the White House.
All of this secrecy does not come cheap. In 2017 the Information Security Oversight Office, the agency tasked with oversight of the system, estimated that the US government spent $18.39 billion (€16.95 billion) on security classification.
Defenders of the system argue it is necessary to protect US methods and sources for obtaining information.
Some politicians, on the other hand, this week argued the system had gone too far, claiming that in some instances they had been told things in classified briefings in SCIFs which they had read already in the New York Times or Washington Post.
Whether or not the system is outdated, breaches of secrecy rules are treated seriously.
Many agencies have rules that classified material should be worked on only in secure facilities. Breaches can lead to dismissal, loss of security clearance or even prosecutions.
But it is not unknown for personnel to take documents home.
Where breaches of security rules are suspected, rank or status does not matter, although some experts say those at the top are more likely to receive fines than imprisonment.
In 2005 Sandy Berger, the former national security adviser in the Clinton administration, was fined $50,000 and sentenced to community service and probation after being found to have hidden documents from the national archives in his clothes and taken them out of the building. He said at the time that he needed them to prepare for dealing with the commission investigating the 2001 attacks on the World Trade Center and the Pentagon.
In 2015 David Petraeus, one of the most prominent American generals in the wars in Afghanistan and Iraq and later head of the CIA, was sentenced to two years’ probation and a $100,000 fine for providing classified information to his biographer, with whom he was having an affair.
In 2019 a former National Security Agency contractor Harold Martin was sentenced to nine years after investigators found thousands of pages of documents, some marked “secret” or top secret” in his home. His defence maintained he was a “hoarder”.
The issue of access to secret files has become hugely controversial after classified material was discovered at the homes of Donald Trump, Mike Pence and current president Joe Biden.
Special counsel are investigating Biden and Trump while the US department of justice is reviewing the Pence case.
The saga has raised questions over whether the system needs to be overhauled.
But what exactly are classified documents?
Christopher McKnight Nichols, Wayne Woodrow Hayes chair in national security studies at the Ohio State University, told The Irish Times they were records that could be viewed or read only by people holding appropriate national security clearances.
He said there were “bright red lines” about classification itself and who could see those documents and where the material could go.
He said the crux of the issue surrounding the material found in the homes of the senior politicians was that the documents had left where they were permitted to be stored, even though some of the individuals may have clearances to see them.
McKnight Nichols said some had asked why such classified material was not on electronic devices. However, he said “hard copy is a better way to secure documents in some cases that have to be mobile than hackable devices that move”.
Part of the problem, according to McKnight Nichols, is that a lot of paper was probably supposed to stay in a secure facility but, for some reason, ended up being sent to a politician’s home and forgotten about.
He said when the politician’s job was over, they may still have had clearances to access such material as long as it was inside a secure facility.
Within the US system there are three main degrees of classification – confidential, secret and top secret.
But McKnight Nichol said within those levels and even above them there were other categories.
Some highly secret records need special compartmentalised clearances.
McKnight Nichol said very secret documents could contain the identity of sources, which, if leaked, could lead to them being in danger.
“There is a mortal risk of losing top secret documents. This is not just some simple kind of problem that is semantics about what counts and does not count. At the highest level some of these things are very much life and death.”
McKnight Nichol said over recent years there had been an enormous rise in the amount of data classified in the US as well as in the numbers of those who had security clearances.
He said since 9/11 there had been an approximate five-fold increase in terms of classification, if not more.
In some cases a document drawn from various open sources can be classified, particularly if it has suggestions of actions that could be taken.
“The world we live in right now is one of hyper-classification related to intelligence and the US government.”
He backs calls for the system to be looked at again.
Last summer the Information Security Oversight Office said in a report to Biden that there was a “dire need” for reform of the process including elimination of the “confidential” level of classification.
It said “one of the most effective ways to shore up Americans’ belief in their government is to modernise its outdated systems for classifying and declassifying national security information”.
In light of the controversy over the Trump/Biden/Pence documents, there are growing political calls for reform, at least for changes to the system of reviewing material held by senior politicians as they leave office.
“Clearly the process is broken,” the Florida republican congressman Mike Waltz told Fox News.
“We’ve got to take a hard look at the General Services Administration and how they and the intelligence community pack these documents [and] get them to wherever the president or vice-president is going.”