This isn't the first time a U.S. President is facing impeachment, and it likely won't be the last.
Donald Trump is the fourth president to face an inquiry. It's something we've seen play out before, but not like this.
If you rewind back to 1868, Andrew Johnson was first president to face impeachment for firing an official without the senate's consent.
"He, throughout history, is the president who came closest to becoming impeached,” said Nina Moore, the Colgate University Political Science chair and professor. “He survived impeachment by one vote in the senate."
For an impeachment, a majority vote must pass the House of Representatives. If it gains an additional two-thirds majority in the senate, the president is removed.
In 1974, voting didn't take place because Richard Nixon decided to resign.
"Next is Bill Clinton,” said Moore. “It was less the affair with Monica Lewinsky, but rather the fact that he lied about it. It's usually the cover-up more than the initial act itself that propels the House toward considering impeachment."
However, Moore says there are no secrets when it comes to Donald Trump's impeachment.
"The president has admitted to including in his conversation with the Ukraine president a request for investigation,” said Moore. “We have very concrete evidence here.”
It may move the process quicker, compared to previous proceedings which took months.
"The speaker has said it's important for the Democrats to move judiciously, but also expeditiously,” said Moore. “This is probably their last chance to move forward with an impeachment to work in their advantage."
However, Moore believes there are some similarities. She believes Trump will have the same fate as Johnson and Clinton— impeached but not removed.
"You need a two-thirds vote,” said Moore. “Ninety-seven percent of Republicans continue to support Trump, and the American public has not been too keen on impeachment either. "
Regardless of the outcome, this is a case that will go down in history.
The political professor also believes officials who failed to say something and took part in the cover-up will also be under fire.