President Donald Trump’s promise to shake things up in Washington has brought us back to unpleasantly familiar territory: talk of impeachment and obstruction of justice, this time involving the investigation into the Trump campaign’s dealings with Russia. But, just as it was with Richard Nixon and Bill Clinton, it is imperative to understand what the Founding Fathers intended when they created the remedy of impeachment, and how allegations of obstruction fit into the constitutional framework for holding a president accountable for misconduct in office.

The framers established impeachment as a last resort, a check to be used to deal with presidential misconduct when all other mechanisms failed. Impeachment cannot and should not be done hastily, nor should it be done for reasons so flimsy they suggest politicians are merely jockeying for political advantage rather than protecting constitutional values.

The more that impeachment proceedings appear to be rushing to judgment or driven by partisanship, the less credibility they ultimately have. The Clinton and Nixon examples offer crucial lessons about the importance of slowing down and ensuring that the public is confident that the gravity of the alleged conduct warrants the extraordinary and fundamentally undemocratic remedy of Congress removing the president from office.

The Clinton episode offers a cautionary tale. In 1998, independent counsel Kenneth Starr’s office had spent months investigating the possibility that Clinton had lied under oath about the nature of his relationship with Monica Lewinsky and then, according to Starr’s referral to Congress for impeachment proceedings, obstructed justice by trying to conceal and destroy evidence of that relationship.

Yet the failure of the House to undertake its own fact-finding, and its reliance instead solely on Starr’s findings, made it easier for Clinton and his defenders to attack the impeachment as both a rush to judgment and not being properly grounded in misconduct involving the president’s abuse of official powers. The Senate quickly disposed of the matter when it was obvious it lacked the votes to meet the two-thirds threshold for a conviction.

The more deliberate the inquiry, the better chance that the American people will have confidence in it. For Nixon, the process that led to his resignation took more than two years, and the scope of wrongdoing that those investigations revealed was breathtaking.

The House Judiciary Committee and a Senate select committee undertook meticulous fact-finding, which ultimately uncovered the evidence that Nixon had taped every conversation in the White House.

Three days after the Supreme Court ordered Nixon to turn over dozens of taped conversations, the House Judiciary Committee approved three articles of impeachment, including one charging that Nixon obstructed justice by paying hush money to the Watergate burglars. Twelve days later, Nixon resigned. Ever since, people on both sides of the aisle have had confidence in the justice of that outcome.

Many advocates on both sides are too eager for a quick resolution of the investigation into Trump’s campaign — Democrats to remove the president from office and Republicans to exonerate him. Moving too quickly not only risks a sloppy and incomplete investigation but also subjects the outcome to claims of either a whitewash or of overturning the results of an election held just months ago.

Special counsel Robert Mueller, a former FBI director, comes to the task with a reputation of impeccable integrity, just as Archibald Cox did when he was appointed as Watergate special prosecutor. If he conducts the investigation as expected, rigorously and impartially, the public will likely have a great deal of confidence in the outcome, whatever it may be.

Impeachment is serious business, perhaps the most serious other than going to war that Congress ever contemplates. Any impeachment inquiry must be conducted thoroughly and preferably with bipartisan support.

Those eager to get started must remember: If not done properly the first time, there might not be another chance.