Attorney General Merrick Garland named a special counsel to oversee criminal probes of Donald Trump's possible mishandling of classified documents at his Florida home, as well as key aspects of the sprawling Jan. 6 investigation — acknowledging the political sensitivity of investigating a former president who is again seeking office.

Garland announced his decision Friday afternoon, tapping Jack Smith, a longtime federal prosecutor who has in recent years been working at the International Criminal Court at The Hague. The announcement comes three days after Trump formally declared himself a 2024 candidate for president.

"Based on recent developments, including the former president's announcement that he is a candidate for president in the next election, and the sitting president's stated intention to be a candidate as well, I have concluded that it is in the public interest to appoint a special counsel," Garland said at the Justice Department.

A special counsel appointment "is the right thing to do," the attorney general said. "The extraordinary circumstances presented here demand it. Mr. Smith is the right choice to complete these matters in an even-handed and urgent manner."

Both Garland and Smith pledged that the appointment will not slow down the investigations.

"I intend to conduct the assigned investigations, and any prosecutions that may result from them, independently and in the best traditions of the Department of Justice. The pace of the investigations will not pause or flag under my watch," Smith said in a written statement. "I will exercise independent judgement and will move the investigations forward expeditiously and thoroughly to whatever outcome the facts and the law dictate."

Garland signed a two-page order authorizing the special counsel to take over "the ongoing investigation into whether any person or entity violated the law in connection with efforts to interfere with the lawful transfer of power following the 2020 presidential election or the certification of the Electoral College vote held on or about January 6, 2021, as well as any matters that arose or might arise directly from this investigation."

The order said the special counsel will not be responsible for cases involving those who were physically present at the Capitol on Jan. 6 - leaving those to the Washington, D.C. U.S. Attorney's office which has been pursuing those investigations since the day of the riot. So far, more than 900 people have been charged.

Well before Friday's announcement, Justice Department officials discussed the possibility of appointing a special counsel to take over investigations involving Trump — such as the Mar-a-Lago case or the attempts to prevent Joe Biden from ascending to the presidency after the 2020 election — if Trump formally declared himself a candidate, according to people familiar with the matter who spoke on the condition of anonymity to discuss private deliberations.

Some former Justice Department officials had urged the attorney general not to appoint a special counsel, arguing it would delay charging decisions deep into the 2024 election cycle, which could be damaging to both the political process and the department. Other former federal prosecutors contend that Garland has little choice but to make such an appointment, since this is the type of scenario in which the special counsel regulations were meant to be applied.

By comparison, Robert S. Mueller III - appointed by Trump deputy attorney general Rod Rosenstein — spent about two years as special counsel probing alleged links between Russian election interference and the Trump campaign. Special counsel John Durham was appointed more than two years ago by a different Trump attorney general, William P. Barr, to continue investigating the origins of that Russia investigation; Durham is still serving as special counsel and is expected to end his work in coming months.

Friday's order also authorizes Smith to pursue the investigation of possible mishandling of national defense secrets at Mar-a-Lago, Trump's Florida residence and private club, as well as possible obstruction, or destruction of government records related to that probe. Smith is authorized to investigate any potential cases that arise from that investigation and to refer to other federal prosecutors any potential cases that may fall outside the scope of his work.

Many other political candidates have been investigated while they ran for office without the appointment of a special counsel - including Hillary Clinton, Trump's Democratic opponent in 2016. The FBI investigation into Clinton's use of a private email server for government matters was opened in mid-2015, continued throughout the primaries, was closed just before the nominating convention and then publicly reopened less than two weeks before Election Day.

But some legal experts had called for a special counsel to take over the high-stakes probe relating to Trump. The Mar-a-Lago investigation, in particular, has accelerated in recent months as investigators interviewed key witnesses and secured important video surveillance and other evidence.

Justice Department regulations say the attorney general will appoint a special counsel, essentially a prosecutor handpicked to tackle a particularly criminal investigation, if a case meets several criteria, specifically: that an investigation is warranted in a way that presents a conflict of interest for the Justice Department "or other extraordinary circumstances," and that under those circumstances "it would be in the public interest" to appoint a special counsel to handle the case.

Critically, a special counsel would still report to the attorney general, who would have the ultimate authority on what to do about the evidence.

Garland made that point earlier this year when asked at a Senate hearing why he had not appointed a special counsel to investigate Hunter Biden, the president's son, who is the focus of a long-running probe involving his business dealings and taxes.

"This is a fact and law determination in each case," Garland told the lawmakers, adding that special counsels "are also employees of the Justice Department" - meaning they still report to the attorney general.

Garland's decision to appoint a special counsel was first reported by the Wall Street Journal.

Smith's career as a prosecutor began in Manhattan in the early 1990s, where he earned a reputation as a hard worker.

"I don't think I was very talented, but you field a lot of groundballs, you're a good shortstop," Smith once told the Associated Press about those early days.

He went on to spend nearly a decade as a federal prosecutor in Brooklyn, before leaving that job in 2008 to become a war-crimes prosecutor at the International Criminal Court.

Smith eventually returned to the Justice Department, taking over the Public Integrity Section at a time when it had been battered by an embarrassing reversal of the conviction of Sen. Ted Stevens, R-Alaska.

Four years ago, he returned to The Hague to investigate war crimes in Kosovo. Though the special counsel appointment begins immediately, Smith was not at Friday's announcement, due to a recent bike accident that required knee surgery.