On Wednesday, the House Intelligence Committee holds the first televised hearing in its impeachment investigation of President Trump’s dealings with Ukraine. It is just the third time in U.S. history that an impeachment inquiry will be televised.

Democrats see the hearings as an opportunity to sway public opinion further toward impeachment, as The Washington Post previously reported.

But will that actually happen?

A look at the historical precedents — the televised impeachment investigations of President Richard M. Nixon and President Bill Clinton — yields mixed messages.

The Senate Watergate hearings

The thing about Watergate that few remember now is that right after it happened, the public didn’t really care all that much. The break-in occurred in June 1972, and despite newspaper stories from some intrepid young reporters at The Post, Nixon was overwhelmingly reelected five months later.

Even that winter, when the Watergate burglars went to trial, Nixon enjoyed a Gallup approval rating above 60 percent.

“T[he burglary trials] received some coverage on the daily news, but it certainly wasn’t riveting the nation,” said historian Rick Perlstein, author of “The Invisible Bridge: The Fall of Nixon and the Rise of Reagan,” in an interview with The Post.

What changed things forever was the Senate Watergate Committee hearings, which began in May 1973, nearly a year after the break-in. They were televised, gavel-to-gavel, for much of the summer.

At first, the three major networks at the time — NBC, ABC and CBS — aired it live every day. But they worried about losing their usual profitable daytime programming, game shows and soap operas, so they struck a deal to rotate coverage. PBS, which was only a few years old, replayed the hearings in prime time.

The hearings soon became must-see TV anyway, often getting higher ratings than scheduled programming.

Congressional hearings are inherently an “extraordinary theatrical event,” said Bob Thompson, a media studies professor at Syracuse University. And these hearings in particular were loaded with colorful characters. There was Sen. Sam Ervin, the North Carolina Democrat in charge of the hearings, who was prone to both quoting Shakespeare and drawling with faux-humility, “Now, I’m just a simple country lawyer.”

There was the ranking Republican, Sen. Howard Baker (Tenn.), who famously asked (and asked and asked), “What did the president know and when did he know it?” Ironically, that question was meant to exculpate the president, Thompson said.

And then there were the people called to testify. In June, viewers were riveted by White House counsel John Dean’s five days of testimony — his monotone delivery notwithstanding.

“How many times have we seen this [Dean] clip, you know, ‘Mr. President, we’ve got to get behind this; this is a cancer on the presidency.’ One of the great clips of all time,” Thompson said. “We should not underestimate that this was a great American television program.”

Also powerful was the juxtaposition between the witnesses — “the guys with the crew cuts,” as Perlstein put it — and the Senate staffers in the background with “long shaggy hair,” fresh out of law school, “and it turns out they [the Senate staffers] are the tribunes of law and order,” Perlstein said.

“You cannot overemphasize how culturally galvanizing it was for people to see the White House revealed in real time as this kind of criminal warren,” he said.

And the real-time revelations in the testimony were very much by design. Mark Lackritz, who was an assistant to the majority’s lawyer Sam Dash, told the podcast “Slow Burn” in 2017, “We were like script writers of the soap opera.” He recalled learning from a witness, White House aide Alexander Butterfield, that Nixon had a taping system on a Friday, and putting Butterfield under oath to reveal this to the world that Monday.

That bombshell came in July, and by then Nixon’s approval rating had tumbled into the 30s. It also set up the standoff — Nixon’s refusal to hand over the tapes to special counsel Archibald Cox — that led to the Saturday Night Massacre, when Nixon’s attorney general and deputy attorney general resigned rather than follow the president’s orders to fire Cox.

By the time the 319 hours of Senate Watergate hearings had aired, nearly 85 percent of American households had watched at least some of them, Thompson said. In his book, Perlstein describes how some viewers became obsessed: A friend’s brother told him that when he was injured and had to be put in traction, he was “grateful,” because it meant he could spend the summer doing nothing but watching the hearings.

Still, Thompson warned that the power of television to influence public opinion may not have been as great as the power of the evidence against Nixon.

“I think even if those hearings had not been televised, the outcome would have been similar,” he said.

After the hearings, Nixon’s approval rating would never rebound; by the time he announced his resignation on Aug. 8, 1974, it had fallen to 24 percent.

The Clinton impeachment

The Clinton scandal was very much a television event. Ask any American who was alive in the late 1990s and they could likely approximate the exact length of the pause between “I did not have sexual relations with that woman” and “Miss Lewinsky.”

And there was the footage of President Bill Clinton and Monica Lewinsky embracing at a campaign event played in an infinite loop on cable news, and the inevitable “I have sinned” speech.

But none of those televised moments came from congressional hearings. The investigation into Clinton’s affair was all done behind closed doors by independent counsel Kenneth Starr (and frequently leaked to the press). Then the full Starr Report was released to the public in September 1998 and quickly became a bestseller.

So by the time the House voted for an impeachment inquiry that fall, the public already knew everything there was to know, including some details they probably didn’t want to know at all (ahem, the cigar). Hearings were perfunctory at best. There was no new investigation, no new revelations to behold.

Even the trial in the Senate in January and February 1999 didn’t yield memorable moments, though it was televised.

Thompson said the reason for the difference in public interest is clear.

“As one was watching these [Senate Watergate] hearings, there was a sense that you didn’t know how it was going to end,” he said. There was a growing chance that Nixon would actually be removed. But “with the Clinton thing, the ending was pretty self-evident. It was going through the motions.”

Even if the House or Senate had held theatrical hearings a la Watergate, Perlstein doubts they would have mattered.

“I don’t know that there was anything that could move public opinion that much,” he said. “In fact, it might have backfired by showing how threadbare it was.”

The Trump hearings

So what, if anything, can the Nixon and Clinton scandals tell us about the hearings we as a nation are about to encounter?

“No question there’s a theatrical aspect to congressional hearings,” Watergate witness John Dean told CNN on Tuesday. “So they have to give a good show tomorrow. And the show they’ve got to put on is why the president has done something that is so serious that we should entertain the impeachment proceedings.”

But Thompson isn’t sure stagecraft will matter.

“At this point, it falls more toward the side of Clinton than the side of Nixon in terms of unknown outcome,” he said. “Everything we’ve heard so far, it’s pretty obvious what’s going to happen in the House, and then it’s pretty obvious what’s going to happen in the Senate.”

And even if there were Butterfield-size revelations, it still might not matter, he said.

“What’s like nothing I have ever seen before is that it’s like there’s no such thing as a bombshell anymore,” he said. With Watergate, “these were incredibly exciting little bits of data, dramaturgical explosions.” But with Trump, “we’ve had plenty of these already in this story, and they cease to have their narrative impact.”

“It’s like we’ve come into a new age of storytelling,” he said.

Read more Retropolis: