Do this, not that.

In its first five public sessions, the House select committee on the Jan. 6 attack on the Capitol has shown how much it has learned from live hearings in the past.

The committee has absorbed the lessons from high impact undertakings such as the Senate Watergate hearings in 1973. It has also heeded the warnings from past probes that failed to meet expectations — notably the Iran-Contra hearings of 1987.

Some of the lessons have to do with presentation – the live events that viewers have seen and heard. Others have to do with what has not been seen or heard.

Perhaps the first lesson to note is that waiting to build the best case before going public is worth the risk involved.

In one sense, airing all these facts together in this fashion might have had more impact if done right after the attack on the Capitol. Some of the evidence now being presented might have been available in the early months after former President Trump left office.

But assembling it in an orderly and lawyerly fashion and then shaping a clear and cogent manner takes time. And in this case, the flexible schedule for the hearings themselves has allowed for the emergence of still more evidence as they continue.

History will weigh whether the origins of Jan. 6 and the culpability of the former president could have been as thoroughly and persuasively mounted in haste. Past hearings that seized on a moment of outrage or heightened public interest have suffered from a rush to judgment atmosphere and ultimately misjudged the public mood.

That was part of the problem for Iran-Contra. Those joint House-Senate hearings attempted to expose the full involvement of the administration in a years-long scheme that sold U.S. arms secretly to Iran and funneled the profits to anticommunist insurgents in Nicaragua.

In the end, the Cabinet-level figures involved were pardoned or never charged. More than a dozen lesser officials were prosecuted, but only one went to prison. And one of the architects of the scheme, former Marine Lt. Col. Oliver North, parlayed his aggressive performance in the televised congressional hearings into a career in conservative media and politics.

A conversation among Republicans

The second lesson to note is the importance of relying on witnesses who cannot be characterized as partisan. In the Watergate model, the most damning testimony came from deep within the White House conspiracy itself. The key evidence emerged from nonpartisan law enforcement, including the president's own Justice Department and Secret Service.

In the Jan. 6 probe, the most telling testimony against the Republican former president has come from Republicans he appointed, or who supported him and voted for him (and, in some cases, say they would do so again).

At times, especially in the most recent session on June 23, the public hearing seemed to have become a conversation among Republicans, whose individual and personal reactions ranged from shocked to deeply sorrowful. Even the questions were posed by Rep. Adam Kinzinger of Illinois, one of the two Republicans on the panel.

Also delivering opening and closing statements for the minority party was Liz Cheney of Wyoming, who again provided clarity and conveyed her deep sense of distress. Cheney has stepped into the role played by Republican Sen. Howard Baker of Tennessee in the Watergate hearings, speaking for that portion of her party willing to hear the facts and make an independent judgment.

On the first night of hearings, she spoke to history when she said: "Tonight, I say this to my Republican colleagues who are defending the indefensible: There will come a day when Donald Trump is gone, but your dishonor will remain."

Among the Republicans who have testified in person and emerged as heroic are:

And in addition, viewers have seen a variety of other major Republican figures – including Barr and Short – testifying on videotape that the former president's claims of fraud were groundless and that his efforts to block certification of the Electoral College votes on Jan. 6 had no legal basis.

It should be noted that Pence himself, while not a witness, underwent at least a momentary makeover of his image in these hearings. Widely regarded as Trump's totally submissive subordinate, Pence's refusal to play the role Trump assigned him in the overturning of the election recast him in these hearings as a modern-day Horatius at the bridge.

The rare quality of restraint

Another lesson this committee seems to have internalized is the strength to be found in restraint. Simple in a sense, restraint is rare in the House, an institution with more than 400 highly motivated and self-actualizing individuals competing constantly for attention. Typically, congressional hearings devolve into contests between the panel members, distracting from the witnesses and the matter at hand.

The panel includes two Democrats, Adam Schiff of California and Jamie Raskin of Maryland, who had major roles in Trump's two impeachments and have been familiar media figures ever since. Schiff did question witnesses in the fourth hearing, but apart from that he has just been listening — as has Raskin.

This ability to keep the focus on the witnesses and emphasize the non-partisan has helped counter the Republican criticism that the entire investigation is a show trial or, as Trump himself says, a witch hunt.

It has also helped to contain each hearing within a time of two hours or so, relatively brief by the standards of Capitol Hill. The panel members have generally dispensed with lengthy statements. With few exceptions, the testimony of each witness has also been notably succinct.

Overall, the hearings have been handled with an awareness of the TV audience and the attention span that implies. The former ABC news executive who has helped produce the hearings has clearly had a hand in shaping the presentation. And just as the awareness of audience dictates respect for its time, so it demands something to hold its interest.

While these hearings have clearly featured the evidence at hand, they have also included moments of significant emotional power. Anyone watching Arizona's Bowers will not forget how his eyes filling with tears as he talked about his Mormon faith. Anyone watching Judge Luttig choosing each of his words with painstaking care had to sense the depth of his feelings.

But the emotional moments most likely to be remembered came with the appearance of Shaye Moss and her mother Ruby Freeman, who had been poll workers in Fulton County, Ga. When Trump targeted workers at their vote-counting center in his false allegations of fraud — specifically refuted by Georgia state officials as well as by the FBI — both women were targeted by election deniers and received death threats.

"It turned my life upside down," said Moss.

They described their ordeal for the committee, appearing in person on June 21. When that session ended, committee members lined up to shake their hands or give them hugs.

In search of significance

Assessing the cumulative effect after 15 days of televised onslaught, the hearings seem to have done everything they were designed to do. And the impact, for the moment at least, seems at least as great as had been foreseen. No one believes the hearings will transform a nation in which political attitudes have become intransigent, particularly where the former president is involved.

But the hearings were never designed to please only Trump's committed detractors nor to convert his most fervid defenders. Instead, they have displayed a commitment to revealing a record and then asking the questions that are raised by that record. What was going on? Was it intended to subvert the election? If so, is that a crime and how should it be dealt with?

The designers of these public proceedings seem to have studied their predecessors, parsing the past with an eye toward what worked and what did not.

It is too early to say whether the Jan. 6 committee will make a criminal referral to the current leadership of the Department of Justice, or whether that department will act on it if they do. It is not yet clear just how these hearings will alter the complex response Americans have when pollsters ask questions related to Trump.

But even without such measurable substantive results, the contribution of the committee and these hearings is now a forceful part of the record and a powerful influence on the national conversation. It will be part of how the nation remembers the Trump presidency.

And that itself is important.

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