Here is a look at the charges former United States president Donald Trump faces and his possible defences over what the government says was his illegal retention of classified documents at his Florida estate after leaving the White House in 2021.
WHAT IS TRUMP ACCUSED OF DOING?
Trump is being charged with seven criminal counts, including mishandling classified documents and obstruction of justice, according to his lawyer and a source familiar with the matter.
The indictment is under seal and it is unclear whether it will be made public before Trump makes his first appearance in Florida federal court next Tuesday (Jun 13). He proclaimed his innocence on Thursday.
In January 2022, Trump agreed to return 15 boxes of records to the US National Archives and Records Administration, and officials discovered in them more than 700 pages of records marked as classified.
The Justice Department issued a grand jury subpoena in May 2022 asking Trump to return any other classified records. Trump's attorneys later turned over 38 pages marked as classified and attested that all records with classified markings had been returned to the government - a claim that later proved to be false.
In August, the Federal Bureau of Investigation (FBI) conducted a search of Trump's Palm Beach home and seized approximately 13,000 more records, about 100 of which were marked as classified.
Of those, some were marked as "top secret" - the classification level reserved for the country's most closely held secrets.
WHAT CHARGES DOES TRUMP FACE?
The most serious charge is being brought under the Espionage Act, which criminalises the unauthorised possession of national defence information. It is punishable by up to 10 years in prison.
The World War I-era law predates the classification of documents but makes it a crime to wilfully retain national defence information that could be useful to foreign adversaries. Courts have ruled that the information must be "closely held".
Trump is also charged with several counts of obstruction of justice, which criminalises any "intent to impede, obstruct or influence" an investigation.
To prove those allegations, prosecutors will need to show that Trump's actions were intentional and that his goal was to hinder the probe, regardless of whether those efforts were successful.
Trump is also charged with making false statements to investigators.
WHAT ARE TRUMP'S POSSIBLE LEGAL DEFENCES?
Trump has claimed that the investigation is a politically motivated "witch hunt". He will likely argue that he is being selectively prosecuted, citing the fact that President Joe Biden and former vice president Mike Pence have not been charged after it was discovered that both men retained classified records after leaving office.
The Biden documents stem from his time as a vice president and senator.
Trump's lawyers say that the selective prosecution is part of a larger pattern of prosecutorial misconduct, though they have provided few details beyond claiming that investigators violated a legal doctrine that permits people to keep communications with their lawyers private.
The legal hurdles to proving selective prosecution are high.
Legal experts say such claims are usually doomed because defendants must prove that they were intentionally singled out for arbitrary reasons and that prosecutors declined to bring charges against others in similar circumstances.
Unlike Trump, Biden and Pence immediately returned the records and cooperated with efforts to search for additional documents. The Justice Department is investigating the Biden matter and dropped a separate probe of Pence on Jun 1.
Trump has claimed that he declassified the documents before removing them. Presidents have the ultimate authority to classify and declassify documents, though this is typically put in writing and done through established channels. Trump has yet to provide evidence that he declassified the documents.
Trump and his allies have said he had a "standing order" to declassify documents he took from the Oval Office to the White House residence, but Trump has failed to provide any evidence of this as well.
On obstruction, Trump could argue he was simply acting on what he thought was sound legal advice from his lawyers and therefore lacked criminal intent. He could also seek to shift blame to subordinates or accuse them of going rogue.