The FBI's search of Donald Trump's Mar-a-Lago estate has raised critical national security, ethical and legal questions amid outcry from Republicans and other Trump allies.
It came after months of developments involving the former president, the Justice Department and congressional lawmakers and it's believed to be the first-ever search of the residence of a current or former U.S. president as part of a criminal investigation.
Sources have told ABC News the search of Trump's Palm Beach home was connected to a probe into whether Trump improperly took classified documents and other records to Florida after leaving the White House.
MORE: FBI search of Mar-a-Lago raises critical national security questions: SourcesHere is a timeline of what led to the search and events that followed:
On Jan. 19, 2021, the day before Donald Trump leaves the White House, he sends Archivist of the United States David S. Ferriero, a letter naming seven senior officials to handle all future requests about the protection and disposition of his presidential records.
Those officials include his chief of staff Mark Meadows, White House counsel Pat Cipollone and his deputy, Patrick Philbin.
(Sources later tell ABC News that Cipollone and Philbin had been interviewed by the FBI about the documents stored at Mar-a-Lago; Philbin was interviewed in the spring of 2022 but it's not clear when Cipollone's interview occurred. They are the most senior former administration officials known to have spoken with the FBI about Trump's handling of documents.)
All presidential records should have be transferred to the National Archives and Records Administration (NARA) at the conclusion of the Trump administration as required by the Presidential Records Act.
But on Jan. 20, 2021, the day Trump left office, Ferriero reportedly said he watched Trump staff members leave the White House carrying boxes, triggering a review of what the National Archives had actually received.
"I can remember watching the Trumps leaving the White House and getting off in the helicopter that day, and someone carrying a white banker box, and saying to myself, 'What the hell's in that box?'" he told The Washington Post.
MORE: Trump's Mar-a-Lago estate raided by FBI agents, sources confirmIn January 2022, National Archives officials confirm that the agency had recently retrieved 15 boxes of presidential records from the Mar-a-Lago Club that it said had been "improperly" removed from the White House.
Sources tell ABC News that the documents included communications between Trump and North Korean leader Kim Jung Un, as well as a letter from former President Barack Obama to Trump that was left, as is customary, ahead of Trump's inauguration.
Amid criticism, attorneys for Trump say they are searching for any more records they might have, with Trump calling the discussions "collaborative and respectful" and saying it was a "great honor" to work with the National Archives.
MORE: What unsealed Trump search warrant papers suggest about federal investigationAt the end of the month, the National Archives takes the unusual step of confirming news reports that some Trump White House records had been ripped up and then taped back together. The revelation comes as the agency transfers documents to the House select committee investigating the Jan. 6 insurrection.
The National Archives asks the Justice Department to investigate Trump's handling of White House records, a person familiar with the matter confirms to ABC News.
The House Oversight and Reform Committee then announces it would investigate as well, sending a letter to the National Archives seeking more information.
The National Archives confirms that some of the documents in the 15 boxes recovered from Mar-a-Lago in January were marked classified, and that the agency has referred the matter to the Justice Department.
In a letter sent to Rep. Carolyn Maloney, the Democratic chair of the House Oversight Committee, National Archives officials confirm in a public statement that among the records retrieved in January from Trump's Florida home were "items marked as classified national security information within the boxes."
In addition, the letter says that "NARA has identified certain social media records that were not captured and preserved by the Trump Administration."
Trump White House staff also "conducted official business using non-official electronic messaging accounts that were not copied or forwarded into their official electronic messaging accounts," according to the letter.
The House Oversight and Reform Committee expands its investigation into former Trump's White House records, requesting new information from the National Archives about the classified materials Trump allegedly took to Mar-a-Lago after leaving office -- as well as the records Trump is alleged to have ripped up while in the White House.
In a new letter to archivist Ferriero, committee chair Maloney requests a "detailed" inventory of the 15 boxes of White House records the National Archives retrieved from Mar-a-Lago, as well as "all presidential records" that the agency discovered Trump had "torn up, destroyed, mutilated, or attempted to tear up, destroy, or mutilate" while in office.
"I am deeply concerned that former President Trump may have violated the law through his intentional efforts to remove and destroy records that belong to the American people," Maloney writes. "This Committee plans to get to the bottom of what happened and assess whether further action is needed to prevent the destruction of additional presidential records and recover those records that are still missing."
In April, The New York Times reports that the National Archives was instructed by the Department of Justice to end its sharing of documents with the House Oversight Committee, suggesting the FBI was beginning a criminal investigation.
Trump also receives a subpoena for documents related to what he is believed to have failed to turn over to the National Archives, sources familiar with the matter told ABC News.
The subpoena played a role in a June visit to Mar-a-Lago by federal investigators, the sources said.
In May, ABC News reports the Justice Department has opened a grand jury investigation related to Trump's alleged mishandling of classified documents. It's not clear when the grand jury investigation began.
At least one subpoena has been issued to the National Archives and interview requests have been made to some former aides who were with Trump during his last days in office, sources familiar with the matter told ABC News.
"President Trump consistently handled all documents in accordance with applicable law and regulations," a Trump spokesperson says. "Belated attempts to second-guess that clear fact are politically motivated and misguided."
Federal agents visit Mar-a-Lago in June to search for additional materials that Trump was believed to have failed to turn over to the National Archives. During that visit, Trump stops by and greets the agents. During this visit, two lawyers representing Trump are present, sources tell ABC News.
There is also a second subpoena seeking security footage of the Mar-a-Lago club towards the end of June, a source tells ABC News. Trump complied with that second subpoena.
ABC News has confirmed that a lawyer for Trump signed a statement in June that all classified documents at Mar-a-Lago had been turned over to federal investigators.
The investigation sharply escalates when the FBI executes a search warrant at Trump's Mar-a-Lago residence.
"[M]y beautiful home, Mar-A-Lago in Palm Beach, Florida, is currently under siege, raided, and occupied by a large group of FBI agents," Trump says in a statement.
Sources told ABC that the search was related to the 15 boxes of documents -- some classified -- that Trump allegedly took to Mar-a-Lago.
The search, beginning about 10 a.m., focuses on areas of the club where Trump's offices and personal quarters are located, including a storage area in the basement. Trump is not present. (He is in New Jersey preparing to be deposed in a separation investigation in New York.) Federal agents remove several boxes of material.
A senior official briefed on the Aug. 8 events tells ABC News that the Secret Service was notified by the FBI a short time before agents arrived that they would be coming. The Secret Service validated the search warrant and facilitated entry into the residence, in accordance with a court order, the official says. Secret Service agents are not involved in the search.
One of Trump's attorneys later says she was present on the property for the search and, according to court documents, was given a copy of the warrant and an inventory of what investigators took.
Amid calls from Trump, his allies and some of Trump's critics to reveal the purpose and circumstances behind the unprecedented search, Attorney General Merrick Garland speaks publicly for the first time about the search, and the Justice Department files a motion asking the judge to release the search warrant the FBI used and the inventory of what was taken.
His brief remarks reveal that he personally approved the decision to seek a search warrant against the former president, stressing, "the department does not take such a decision lightly."
He also pushes back against what he called "unfounded attacks on the professionalism of the FBI and Justice Department."
Moments after the remarks concluded, Trump posts on his social media platform, Truth Social.
"My attorneys and representatives were cooperating fully, and very good relationships had been established," Trump posts. "The government could have had whatever they wanted, if we had it."
The next day, federal Magistrate Judge Bruce Reinhart approves the Justice Department's request to unseal the Mar-a-Lago search warrant and its property receipt.
The search warrant and an inventory of what was taken reveals that the Justice Department is investigating the potential violation of at least three separate criminal statutes, including under the Espionage Act.
The receipt shows that the federal agency removed dozens of boxes of material, including 11 sets of documents of various classifications ranging from confidential to top secret (TS) and sensitive compartmented information (SCI). Other materials included in the receipt are an item labeled "Info re: President of France," an executive grant of clemency for Trump ally Roger Stone, binders of photos, a "potential presidential record" and a leather-bound box of documents.
Trump has been recorded saying on his Truth Social platform that he will "not oppose the release of documents" related to the search, with his legal team ultimately agreeing to the DOJ's request. (But even before the warrant and related papers are unsealed, Trump was able to release them on his own if he so chose.)
The warrant discloses that as part of the investigation, the Justice Department was looking into possible violations of the Espionage Act, obstruction of justice and criminal handling of government records.
The top Democrat and top Republican on the Senate Intelligence Committee jointly request classified documents taken from Mar-a-Lago.
Sens. Mark Warner, D-Va., and Marco Rubio, R-Fla., the chair and vice chair of the Senate Intelligence Committee, respectively, send a private letter to top intelligence officials and the Justice Department asking for more information the FBI search -- specifically what they said were the classified documents seized and an analysis of any national security threat posed by any mishandling of the information.
News media organizations, including ABC News, ask a judge to release the affidavit supporting the Mar-a-Lago search, arguing it would be in the public interest, but the Justice Department contends releasing it could jeopardize the ongoing investigation, saying it "implicates highly classified material."
"Disclosure of the government's affidavit at this stage would also likely chill future cooperation by witnesses whose assistance may be sought as this investigation progresses, as well as in other high-profile investigations," prosecutors say.
The news media groups argue selective redaction could meet DOJ's concerns.
Trump calls for the release of the "completely Unredacted Affidavit" in a post on Truth Social.
ABC News' Katherine Faulders, Alexander Mallin, Rachel Scott, Benjamin Siegel, William Steakin and Trish Turner contributed to this report.