“People have got to know whether or not their president is a crook.”

Richard Nixon made that infamous declaration during a press conference in November 1973. The American people got an answer on this day 44 years ago, when Nixon resigned the presidency, walking out on the south lawn of the White House to the helicopter that would carry him safely away from the levers of power he had so abused.

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It had taken more than six years for the cloud of corruption around Nixon to catch up with him. During much of that time, his supporters maintained that the negative stories over allegations of wrongdoing were the invention of the East Coast press. That’s not the only thing about those years that sounds familiar today.

The most famous part of Watergate was the breaking into the headquarters of the Democratic National Committee. In those days, you had to commit the crime in person, and Nixon’s men fumbled the job.

In 2016, the servers of the DNC were hacked — a 21st century break-in — most likely by the Russian government. President Donald Trump has not been charged with a crime. No evidence released so far proves that Trump colluded with the Russians.

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But we do know that members of Trump’s campaign, including his own son, leapt at the chance to meet with Russian government-connected messengers who claimed to have dirt on his opponents — which, if they had any at all, they most likely obtained through criminal activity. The president acknowledged the meeting on his own Twitter account this week, calling it “totally legal and done all the time.”

The final chapter of Watergate began when Nixon attempted to shut down a Justice Department investigation into his presidency. That was widely seen as beyond the pale, and it caused a constitutional crisis. Trump hasn’t gone that far, although his presidency began with an attempt to shut down a Justice Department investigation into hacking during the 2016 election. Two days after firing FBI Director James Comey, Trump told NBC’s Lester Holt that he fired Comey to stop the “made-up story” of the investigation, a statement later echoed by Rudy Giuliani, one of the president’s lawyers.

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During Nixon’s presidency, the scandals trickled out over a matter of years. In Trump’s case, they have poured like one of the president’s late-night Twitter storms.

But Nixon’s scandal reached an inflection point when his authoritarian tendencies became too much even for members of his own party. Republicans voted to file articles of impeachment on grounds of obstruction of justice, abuse of power and contempt of Congress. When more started to defect, Nixon crumbled. On the night of August 8, he told the nation that his congressional support had faltered. The country “needs a full-time President and a full-time Congress,” he told the nation, and he would not stay to fight.

For the very health of this country, we need to know that today’s Republicans — like their predecessors — won't let any such high crimes and misdemeanors go unpunished if proven at the top levels of government. They can’t, so to speak, let the president “stand in the middle of Fifth Avenue and shoot somebody” and get away with it, as he famously joked during the campaign.

The question today, on the anniversary of Nixon’s resignation, is one that ought be asked of every Republican candidate for Congress by his or her voters: Where is your red line? What behavior will you not accept from America’s chief executive?

Maybe Robert Mueller’s special investigation will end in no charges for Trump. Maybe it will even clear him. But what if the opposite happens?

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Dan Crenshaw, Ava Pate and Phillip Aronoff, what is your red line? Brian Babin, John Culberson and Pete Olson, are you willing to put country ahead of party? Kevin Brady, Michael McCaul and Randy Weber, can you see yourself voting for articles of impeachment against Trump?

No president is above the law, and any representative must be able to imagine a scenario where the Mueller investigation may reveal an impeachable offense. That investigation has already resulted in two guilty pleas from one-time Trump staffers: former campaign policy adviser George Papadopoulos and former national security adviser Michael Flynn. Trump’s former campaign manager Paul Manafort is currently on trial. Rick Gates, who also worked on the campaign, has testified that he and Manafort committed crimes together.

The American people deserve to know whether our president is upholding the values of the office. And they also deserve to know that, if need be, their representatives in Congress will do the right thing and hold a “crooked” White House accountable.