The House of Representatives on Wednesday will convene the first public impeachment hearings in 20 years and only the third in the history of the modern presidency.

Here are five things to look out for in the investigation into whether Donald Trump sought to push Ukraine into investigating his domestic political rivals:

1 Riveted? Or bored?

Public hearings are not necessary to impeach a president. The point of public hearings is to take the case against the president to the public. So, is the public watching on their televisions? Or did they tune out after the first five minutes of congressional droning and change the channel?

The greatest risk for Donald Trump is that the hearings shift public opinion in a way that Republicans become tempted to abandon him. The greatest risk for Democrats is that people just can’t be bothered to pay that much attention to a complex story.

2 The witness’s chair

Trump’s argument that he did nothing wrong is undercut intuitively by the fact that what he did caused such widespread horror in the ranks of the state department, defense department, national security council and elsewhere.

The public has yet to hear the witnesses speak. Are they persuasive? Are they credible? What do they sound like? Substantive, serious people? Or the “unelected and anonymous bureaucrats” with an axe to grind that Republicans have been characterizing them as?

3 Who is telling the more persuasive story?

The argument that Trump abused the power of his office by leaning on Ukraine to interfere in the 2020 US election appears to be strong, and the evidence for it appears to be substantial – but how well are Democrats making the argument, and how successfully are Republicans rebutting it?

In watching the hearings, will viewers be struck by the audacity of Trump’s alleged misconduct? Or will viewers come away thinking that what Trump did was no big deal?

Both sides have said they will allow staff lawyers to conduct part of the questioning. Are those lawyers getting the extra mileage out of witnesses that members might not?

4 Republican hijinks

In the impeachment inquiry so far, Republicans have used wild tactics, such as invading the secure room where depositions were being taken, to derail and deflect the investigation. What will they do once the cameras come on? Will it descend into chaos?

In advance of public hearings, Republicans moved Representative Jim Jordan, a strident Trump defender, onto the committee, and they demanded that the impeachment whistleblower appear as a witness. They have attacked the process at every turn and pronounced the hearings a “sham”.

Will they manage to turn the impeachment hearings into the kind of self-regarding and incoherent Washington spectacle that Americans love to hate?

5 Trump’s reaction

With all the cable news channels including Fox News planning to carry the impeachment hearings live, there’s a nonzero chance that Trump himself will be watching. The question is whether he will be tweeting. Trump’s reaction could be significant if he attacks the witnesses in a way the public feels is unfair.

Or perhaps the president will hit on a riposte to finally take the impeachment heat off.