President Donald Trump has suggested to aides he wants to pardon himself in the final days of his presidency, according to two people with knowledge of the discussions, a move that would mark one of the most extraordinary and untested uses of presidential power in American history.

In several conversations since Election Day, Trump has told advisers that he is considering giving himself a pardon and, in other instances, asked whether he should and what the effect would be on him legally and politically, according to the two people. It was not clear whether he had broached the topic since he incited his supporters on Wednesday to march on the Capitol, where some stormed the building in a mob attack.

Trump has shown signs that his level of interest in pardoning himself goes beyond idle musings. He has long maintained he has the power to pardon himself, and his polling of aides' views is typically a sign that he is preparing to follow through on his aims. He has also become increasingly convinced that his perceived enemies will use the levers of law enforcement to target him after he leaves office.

No president has pardoned himself, so the legitimacy of prospective self-clemency has never been tested in the justice system and legal scholars are divided about whether the courts would recognize it. But they agree a presidential self-pardon could create a dangerous new precedent for presidents to unilaterally declare they are above the law and to insulate themselves from being held accountable for any crimes they committed in office.

A White House spokesperson did not respond to a request for comment.

Trump has considered a range of pre-emptive pardons for family, including his three oldest children, Donald Jr., Eric Trump and Ivanka Trump; Ivanka Trump's husband, senior White House adviser Jared Kushner; and for close associates such as the president's personal lawyer Rudy Giuliani. Trump has expressed concerns to advisers that a Biden Justice Department might investigate all of them.

Trump, who has told advisers how much he likes having the power to grant clemency, has for weeks solicited aides and allies for suggestions on whom to pardon. He has also offered pre-emptive pardons to advisers and administration officials. Many were taken aback because they did not believe they were in legal jeopardy and thought that accepting his offer would be seen as an admission of guilt, according to the two people.

Presidential pardons apply only to federal law and provide no protection against state crimes. They would not apply to charges that could be brought by prosecutors in Manhattan who are investigating the Trump Organization's finances.

The discussions between Trump and his aides about a self-pardon came before his pressure over the weekend on Georgia officials to help him try to overturn the election results and before his incitement of the riots at the Capitol. Trump allies believe that both episodes increased Trump's criminal exposure, and more potential problems emerged for the president on Thursday when the Justice Department said it would not rule out pursuing charges against him over his role in inciting Wednesday's violence.

"We are looking at all actors, not only the people who went into the building," said Michael R. Sherwin, the top federal prosecutor in Washington.

As aides urged Trump to issue a strong condemnation on Wednesday and he rejected that advice, the White House counsel, Pat Cipollone, warned Trump that he could face legal exposure for the riot given that he had urged his supporters to march to the Capitol and "fight," according to people briefed on the discussion. Trump had appeared to White House aides to be enjoying watching the scenes play out on television.

Beyond that, the extent of Trump's criminal exposure is unclear. The special counsel, Robert Mueller, outlined 10 instances in which Trump may have obstructed justice but declined to say whether Trump broke the law, citing legal and factual constraints of prosecuting a sitting president. In 2018, federal prosecutors in New York named Trump as a conspirator in an illegal campaign finance scheme.

Pardons can be broad or narrowly tailored. White-­collar defense lawyers said that Trump would be best served by citing specific crimes if he pardoned himself, but such details could be politically damaging by suggesting that he was acknowledging he had committed those crimes.

A self-pardon would complicate the already fraught question for the Biden Justice Department about whether to investigate and ultimately prosecute Trump. Democrats and former Justice Department officials contend that if Trump pardons himself and the Justice Department declines to prosecute Trump, it will send a troubling message to Americans about the rule of law and to future presidents about their ability to flout the law.

Trump has eschewed the formal Justice Department process set up to ensure pardons are handed out fairly. Instead, he has used his pardon power unlike any other president to help allies, undermine rivals and push his own political agenda. Of the 94 pardons and commutations Trump has granted, 89% were issued to people who had a personal tie to Trump, helped him politically or whose case resonated with him, according to a tabulation by Jack Goldsmith, a Harvard law professor and former top Justice Department official in the George W. Bush administration.