The late Sen. Howard Baker’s enduring question during the 1973 Senate Watergate Committee investigation is coming to the fore again: “What did the president know and when did he know it?”

President Donald Trump’s efforts to get former (and fired) FBI Director James Comey to “go easy” on an investigation of former (and fired) National Security Advisor Michael Flynn may or may not constitute an obstruction of justice. Communications on the part of Flynn and other Trump associates with Russian officials during the 2016 presidential campaign may or may not have anything to do with Russian interference in the election.

But it’s now clear that these efforts and communications have become focal points of the investigation that Special Counsel Robert Mueller is conducting since he was named to that post the day after Trump fired Comey on May 9.

The circumstances bear considerable resemblance to those under which the Senate Watergate Committee investigated a break-in and bugging of the Democratic National Committee’s offices by Republican operatives during the 1972 presidential campaign. The current investigation was triggered by cyber intrusions on the part of Russian operatives to hack email accounts of the Democratic National Committee and of Hillary Clinton’s campaign chairman John Podesta, and then releasing a trove of damaging documents via Wikileaks.

Yet in the case of Watergate, Baker (who was vice chairman of the committee) didn’t really get answers to his seminal questions. It was never determined whether President Richard Nixon ordered or was even aware in advance of the DNC break-in.

And in the investigation of the far-flung, almost surreal cover-up that ensued, the Senate Committee was rebuffed by Nixon’s refusal to hand over pertinent documents on grounds of executive privilege. On Baker’s recommendation, the committee sued Nixon to obtain them. But the federal courts dismissed the suit for lack of jurisdiction over a dispute between the legislative and executive branches of government.

Only later did Special Prosecutor Leon Jaworski prevail in a suit to obtain Nixon’s damning tapes as evidence in a criminal case against former presidential aides John Mitchell, Bob Haldeman, and John Ehrlichman. A unanimous U.S. Supreme Court ruled in United States v. Nixon that “the duty of the Judicial Branch to do justice in criminal prosecutions” takes precedence over executive privilege “absent a claim of need to protect military, diplomatic or national security secrets.” Within two weeks after release of the tapes, Nixon resigned rather than face certain impeachment.

The Watergate experience is relevant to the current investigation in establishing that a prosecutor is better equipped to get to the bottom of things than a Congressional committee. Yet, as matters stand, no fewer than four such committees are clambering to get in on the investigative action with what could be duplicative if not deleterious results.

The Senate Intelligence Committee has taken the lead with hearings at which both James Comey and Attorney General Jeff Sessions have testified about the circumstances surrounding Comey’s firing. Both the committee’s chairman, Republican Richard Burr of North Carolina, and its ranking Democrat, Mark Warner of Virginia, have conducted themselves with aplomb. But as every committee member has gotten a turn at questioning the witnesses, partisan rancor has emerged.

After Sessions testified that he couldn’t divulge conversations with the president in a public hearing, Democrat Ron Wyden of Oregon lambasted him by proclaiming, “I believe the American people have had it with stonewalling.” To which Sessions retorted that, “I am not stonewalling. I am following the established policies of the Department of Justice. You don’t walk into a hearing and reveal confidential conversations with the president of the United States.” When Wyden accused Sessions of violating the terms of his recusal from the Russia investigation and Sessions insisted he hadn’t, Wyden shot back, “That answer doesn’t pass the smell test.”

Now, the Senate Judiciary Committee is planning to hold a separate hearing on Comey’s resignation. And at least two House committees are also probing even though their respective chairmen have either recused themselves or resigned.

The chairman of the House Intelligence Committee, Devin Nunes of California, compromised himself by racing to the White House with a discovery that the National Security Agency had “unmasked” the identities of three Americans who’d had telephone conversations with foreigners who were subjects of NSA surveillance. (The agency is not supposed to spy on U.S. citizens.)

The only one of the three whose name has been highly publicized was Trump’s then newly appointed Director of National Security, Michael Flynn. It turned out that on the day the outgoing Obama administration imposed sanctions on Russia for election meddling, Flynn had five telephone conversations with Russian Ambassador Sergey Kislyak. Flynn denied having any such conversations that had anything to do with the sanctions. But when the media brought out that transcripts showed he had lied, Trump sought Flynn’s resignation. Yet the very next day the president asked then FBI Director Comey to “go easy” on Flynn because “He’s a good guy.”

It’s also been widely reported that Flynn received payments from Russian entities without making the disclosures that are required of former military officers. (Flynn had been an Army general and director of the Defense Intelligence Agency before joining the Trump campaign.)

Trump’s relationship with Flynn and intercessions on his behalf will no doubt be central to Mueller’s investigation of possible obstruction of justice. When Mueller was appointed Trump tweeted that he was “100 percent sure” he would testify under oath to the special counsel. But that was before Trump learned that he’d become the subject of investigation and turned his wrath on Mueller.

Whether Mueller can compel Trump’s testimony is an open question. Some commentators believe it will be governed by the Supreme Court’s decision in the Nixon case. But that only applied to criminal prosecutions, and it’s well established that a sitting president can’t be indicted or convicted of a crime—only impeached by Congress.

Meanwhile, the best thing Trump can do to protect himself from further exposure is to close his Twitter account because his tweets have been a major source of self-inflicted damage.

Corrected: A previous version of this story mistakenly listed former Sen. John Warner of Virginia, rather than current Sen. Mark Warner.

Joe Sullivan

Joe Sullivan is the former owner and publisher of Metro Pulse (1992-2003) as well as a longtime columnist covering local politics, education, development, business, and tennis. His new column, Perspectives, covers much of the same terrain.