WASHINGTON – Here’s a reality check for Democrats wanting to impeach President Donald Trump: You probably can do it.

But it’s unlikely you'll be able to remove him from office.

House Speaker Nancy Pelosi is under pressure from some Democrats to start impeachment proceedings against Trump following the release of special counsel Robert Mueller’s report on Russian meddling in the 2016 election.

Pelosi understands the challenges awaiting Democrats if they should pursue impeachment proceedings and has tried to swat away such talk whenever it comes up.

Impeachment would be one of the most divisive paths the country could take, she warned this week, yet she did not shut the door completely.

Here are a few things to know about the impeachment process and how it works:

What is impeachment?

Americans often equate impeachment with the removal of a president or other federal officials from office for committing a crime.

But that’s technically incorrect.

Impeachment is nothing more than the approval of formal charges against a president, vice president or other federal officeholder who stands accused of committing a crime. It’s like an indictment in a criminal proceeding.

Once an officeholder is impeached by the House of Representatives, a trial is held by the Senate to determine whether the accused is guilty of the charges. If a guilty verdict is returned, only then can the accused be removed from office.

Why is Trump under fire?

Mueller spent months investigating Russian interference in the 2016 election and whether anyone in Trump’s campaign conspired with Moscow.

Mueller’s long-awaited, 448-page report, released last week, detailed multiple contacts between Russian operatives and Trump associates during the campaign, but investigators didn’t find any evidence of a criminal conspiracy.

The report does document a series of actions by Trump to derail the special counsel's investigation and cites 10 instances of possible obstruction by the president. Mueller’s office did not conclude Trump's actions were illegal but also pointedly refused to clear him of wrongdoing.

Attorney General William Barr later determined that the president’s conduct did not constitute a crime. Some House Democrats, however, seized on what they called the "damning details" against Trump and argued his actions were illegal and should be the basis to begin impeachment proceedings.

Who files impeachment charges?

The U.S. Constitution gives the House the sole power to impeach a federal official. Individual House members can introduce impeachment resolutions like ordinary bills or the House could initiate impeachment proceedings by passing a resolution authorizing an inquiry.

The House Judiciary Committee, which has jurisdiction over impeachment proceedings, decides whether to pursue articles of impeachment against the accused official and can hold hearings to review the accusations. If the committee votes to approve articles of impeachment, the formal charges then move to the full House for consideration.

The House votes on each of the articles of impeachment separately and can approve them with a simple majority of those voting. If all 435 House members vote, then just 218 votes would be needed.

If the articles are adopted, the accused has formally been impeached.

What happens next?

Once an officeholder has been impeached, the proceedings shift to the Senate, which holds a trial and decides whether to convict the accused and remove him or her from office.

The House appoints members to manage the trial and act as prosecutors in the Senate. The chief justice of the Supreme Court presides over the proceedings. At the end of the trial, which can last for weeks or even months, the Senate votes whether to convict the accused on each of the charges.

A two-thirds majority, or 67 senators, is needed to convict and remove the accused from office.

More:Mueller report revives Trump impeachment talk, even as Democratic leaders try to tamp it down

What's an impeachable offense?

Article II, Section 4 of the Constitution says the president, vice president and other federal officials can be removed from office upon conviction for treason, bribery and “other high crimes and misdemeanors.”

But what are “high crimes and misdemeanors?”

“This is one of the most famously contested phrases in all of constitutional law,” said Joshua Matz, one of the authors of the book “To End a Presidency: The Power of Impeachment.”

“Simply put,” Matz said in an interview with USA TODAY, “impeachable offenses involve an abuse of power, a betrayal of the nation or a corruption of the office for private benefit that poses a substantial and ongoing risk of harm to the ongoing constitutional order if the president is allowed to remain in office.”

Under that standard, a president can’t be impeached simply over policy disagreements, partisan differences, negligence or recklessness, or for making poor personnel decisions.

“The president has to have done something bad, very bad,” Matz said.

Who has been impeached?

The House has initiated impeachment proceedings more than 60 times, but less than a third have led to full impeachments, according to the House’s History, Art and Archives website.

Just eight of those impeached – all federal judges – have been convicted and removed from office by the Senate. Officeholders impeached include 15 federal judges, a cabinet secretary (Secretary of War William Belknap in 1876), a U.S. senator (William Blount of North Carolina in 1797) and two presidents.

President Andrew Johnson was impeached in 1868 after a political conflict with Congress involving his Reconstruction policies after the Civil War and his removal of Secretary of War Edwin Stanton. Thirty-five senators voted to find him guilty of the charges – a single vote short of the two-thirds majority required for conviction and removal from office.

More than a century later, President Bill Clinton was impeached for perjury and obstruction of justice in the wake of his extramarital affair with White House intern Monica Lewinsky. The Senate failed to muster the two-thirds majority for a conviction on either of the charges, and Clinton went on to serve the remainder of his term in office.

President Richard Nixon was on the verge of impeachment in 1974 over his role in the Watergate scandal. The House Judiciary Committee approved three articles of impeachment against him alleging obstruction of justice, abuse of power and contempt of Congress. But Nixon resigned from office before the charges were taken up by the full House.

Is there a case for impeachment of Trump?

Impeachment expert Matz isn’t sure.

“The Mueller report makes it clear the president endeavored to obstruct an ongoing federal investigation and develops a strong circumstantial case that he may have done so for improper reasons,” he said.

But Congress must do more investigating and fact-finding to determine whether the allegations outlined in the report support articles of impeachment, Matz said.

The Mueller report “does not clinch the case one way or the other in my view,” he said.

If the House were to initiate impeachment proceedings, it’s certainly possible they would have the votes to approve impeachment articles against Trump. Democrats hold a 235-197 majority in the House – well above the 218 votes needed to impeach.

In the Senate, however, Republicans hold a 53-47 advantage over Democrats. To remove Trump from office, Democrats would have to persuade at least 20 Republicans to vote for his conviction. That won’t happen unless something extraordinary happens to cause his support to dwindle among GOP senators.

More:Trump took steps to fire Mueller, stop probe after campaign welcomed Russian dirt on Clinton, Mueller report says

Can impeachment be appealed?

Trump suggested Wednesday he’d ask the Supreme Court to intervene if Democrats tried to impeach him.

Matz said the comment shows Trump has “a fundamental misunderstanding” of the Constitution and how the impeachment process works.

The framers of the Constitution explicitly refused to give the Supreme Court a role in the impeachment process, he said, in part because they feared a president would pack the courts with justices who share his world view and "they didn’t want a president to choose his own judge in an impeachment."

Nearly three decades ago, a federal judge from Mississippi asked the courts to overturn his perjury conviction and removal from office. But in a 1993 decision written by Chief Justice William Rehnquist, the Supreme Court held that the courts may not review such cases because the Constitution makes it clear the House has the sole power of impeachment and the Senate has the sole power to try impeachment articles.

"That phrase – 'sole power' – at the very least indicates an overwhelming presumption against any Supreme Court involvement in the substance of an impeachment proceeding," Matz said.

In other words, "President Trump’s apparent belief that the justices he appointed to the Supreme Court will save him from impeachment is gravely misguided," he said.

Contributing: David Jackson

More:Trump hopes for Supreme Court's help on impeachment. He should check with Brett Kavanaugh.

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