Former US Secretary of State Hillary Clinton speaks during the Time 100 Summit event on April 23, 2019, in New York.

Mueller did not conclude that Trump had committed a crime, but the report laid out analysis and evidence while making it clear that the investigation did not exonerate him. Instead, Mueller's report suggested that it should be a matter for Congress to debate. Attorney General William Barr, however, decided not to charge Trump .

"I think there's enough there that any other person who had engaged in those acts would certainly have been indicted," Clinton said at the TIME 100 Summit in Manhattan. "But because of the rule in the Justice Department that you can't indict a sitting president, the whole matter of obstruction was directly sent directly to the Congress."

Former Secretary of State Hillary Clinton said Tuesday that President Donald Trump only avoided obstruction of justice charges following the release of special counsel Robert Mueller's report because of the Justice Department's rule barring the indictment of a sitting president.

Clinton, whom Trump defeated in the 2016 election, also called for the release of an unredacted version of Mueller's report. "I'm really of the mind that the Mueller report is part of the beginning. It's not the end," she said.

"Every American who cares about holding our adversaries accountable, looking to prevent what happened from ever happening again, should take the time to go through," she added.

As more high-profile Democrats call for impeachment proceedings against Trump, Clinton emphasized that the process should "be something undertaken in a really serious, diligent way, based on evidence."

"I have a weird personal history about impeachment," she said, referring to her time as a staff attorney for the House Judiciary Committee during the Watergate investigation. "It shouldn't be a preordained conclusion. It should be based on evidence, not on partisan advantage."

Nixon resigned before he could be impeached. Clinton's husband, Bill Clinton, was impeached during his second term as president, but was not removed from office.

Sen. Elizabeth Warren of Massachusetts has called on elected officials to begin impeachment proceedings, along with other 2020 Democratic candidates including Sen. Kamala Harris of California and Rep. Seth Moulton of Massachusetts.

Meanwhile, Trump has railed against calls for his impeachment. He wrote on Twitter on Monday that "Only high crimes and misdemeanors can lead to impeachment."

"There were no crimes by me (No Collusion, No Obstruction), so you can't impeach," Trump said.

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