WASHINGTON - After nearly a year and 1,000 interviews - including of former President Donald Trump's family members and some of his closest advisers - the congressional committee investigating the Jan. 6 insurrection at the Capitol is ready to share its findings. 

In hearings that began Thursday and last throughout the month, it will tell the story of how the attack unfolded, detail Trump and his allies' role in it and say how Congress can try to prevent such an attack from happening again.

Here are six questions the committee expects to answer about Jan. 6.

1. How much responsibility for the violence falls on Trump?

Some committee members have hinted they will aim to prove Trump's culpability for Jan. 6 in a couple of respects: that he incited the attack on the Capitol, and that he broke federal law by trying to stop lawmakers from certifying Joe Biden's win. It is a crime to obstruct an official proceeding of Congress.

They've interviewed former aides and administration officials - including the No. 1 and No. 2 officials at the Justice Department at the time, Jeffrey Rosen and Richard Donoghue - who testified that they told Trump, in no uncertain terms, that he lost the 2020 election.

But to build the case that he committed a crime, the committee would need to demonstrate that Trump and his allies specifically planned to disrupt the congressional counting of electoral votes. It will be key to explain why he made no effort to tell the rioters to leave for 187 minutes as the attack unfolded, even as some of his Republican allies pleaded with his chief of staff to get the president to speak up. He eventually filmed a video telling the rioters to "go home, we love you. You're very special."

The committee has debated internally whether to go so far as to accuse him of a crime.

Rep. Liz Cheney of Wyoming, the top Republican on the panel, has raised the question of whether Trump committed a crime. But others argue that it could be viewed as a partisan overreach, given that Congress doesn't have any prosecutorial powers. The most it could do is refer Trump to the Justice Department, recommending that he be charged with a crime, and the Justice Department has been cautious when it comes to investigating the president and his top aides.

Still, it would be a big deal for a congressional committee to formally accuse a former president of a crime. Trump would go down in the history books as a president twice impeached and formally accused by Congress of breaking the law to stay in power.

2. How did Trump and his allies use the levers of government to try to keep him in power?

Trump galvanized support within the Republican Party and the federal government to fight his loss. Top officials in the White House and Justice Department told him what he wanted to hear, including that he could seize voting machines and have the military order a redo of the election. A majority of Republicans in the House of Representatives voted to reject electors in states that Trump lost.

But to what extent did government officials actively help Trump plan to overturn the election results?

To find that out, the committee recently took the extraordinarily aggressive step of subpoenaing its own colleagues - five House Republicans, including the top one, Kevin McCarthy - to learn what they knew about the attack and Trump's actions that day.

"These are people who participated in the rally, were on the phone with the president, who the president reportedly told to rescind the election and one of whom may have been pursuing pardons for those involved," committee member Rep. Adam Schiff, D-Calif., has said about these House Republicans.

It's unclear whether those lawmakers will testify. They could drag out their fight over a subpoena in court until after Republicans likely win back control of the House in November.

The committee has also been focused on what role the Justice Department played in casting doubt on the election results. How close was the Justice Department - specifically a high-ranking Trump ally, Jeffrey Clark - to publicly saying that it was concerned about election fraud claims in battleground states such as Georgia?

Such a statement would have lent weight to Trump and his allies' baseless claims even though they been thrown out in courts across the country, including by Trump-appointed and other Republican judges.

The committee also seeks to shed light on the actions of officials such as then-White House Chief of Staff Mark Meadows, who played a major role in putting people who had plans to overturn the election results in front of the president, reports The Post's Michael Kranish.

But in the government, there were also strong pockets of resistance to Trump and his allies. Justice Department officials threatened mass resignations if Trump put Clark in charge of the Justice Department. (Trump never did install Clark in the top job.)

The committee also will delve into efforts to put forward alternate slates of electors who would vote for Trump. Republican officials in at least five states falsely declared that Trump won and that the alternates were the true electors for their states; the Justice Department is reviewing what happened.

3. How did so many people come to believe - and act on - Trump's lies about the election?

The committee is particularly interested in unraveling the origins of this mass radicalization, which manifested in the most serious attack on the Capitol since the War of 1812 - this time, led by ordinary Americans rather than foreign soldiers.

The Washington Post's Jacqueline Alemany, Josh Dawsey and Amy Gardner report that the committee plans to spend a significant amount of time on this topic: The panel wants to flesh out for the public what extremists and extremist threats look like, and how disinformation spreads. It's also focused on how right-wing groups got involved in the attack.

The government in January charged the leader of the Oath Keepers, Stewart Rhodes, and 10 others with seditious conspiracy, a rare charge alleging they conspired to overthrow the government. And this week, seditious conspiracy indictments were handed down against Henry "Enrique" Tarrio, the former longtime chairman of the Proud Boys, and four of his top lieutenants.

But the committee is also up against a wider cultural tolerance, within the Republican Party, of what happened on Jan. 6 and of attempts to undermine the 2020 election. Top Republican lawmakers - even former vice president Mike Pence, whose life was threatened by the attackers - have downplayed what happened. It's now a badge of honor in some circles to have been in Washington D.C. protesting election results or to be labeled an insurrectionist, even as the courts debate whether people who participated can run for office. Republicans in Pennsylvania just nominated Doug Mastriano, an election denier who passed through police barricades at the Capitol on Jan. 6, for governor. (He has said he did not enter the building and left when he realized the protest had turned violent.)

4. What is the connection between officials' actions and ordinary people's violence on Jan. 6?

As Congress was convening that day to certify each state's electoral votes, Trump took to a stage down the street from the Capitol and told his supporters: "I said something is wrong here, something is really wrong, can't have happened, and we fight. We fight like hell, and if you don't fight like hell you're not going to have a country anymore," he declared.

He had spent months before that falsely claiming in apocalyptic, sometimes violent language that the election was stolen from him. ("Be there, be wild," he had tweeted, inviting his supporters to Washington for a "Stop the Steal" rally taking place just before the final step in the presidential certification process.)

Much of the Republican Party apparatus geared up to support his election fraud claims. A majority of House Republicans signed onto a baseless, last-ditch lawsuit led by Republican state attorneys general asking the Supreme Court to step in and overturn the results in swing states Trump lost. Republican lawyers took election fraud claims to courts across the country - and often got laughed out of court. Conservative Republican senators announced they would reject certain states' results on the 6th; one of them, Josh Hawley, R-Mo., was photographed giving Trump supporters a fist pump the day of the attack. Two local Republican election officials in Michigan originally voted to reject Detroit's election results before changing their minds after an outcry from voters there. The Republican National Committee cheered on much of this.

The question the committee must answer is: How is all this connected to the attack? Was the insurrection a spontaneous outburst led by some bad actors in the crowd? Or is there evidence the violence was fed - or even coordinated - by government officials and the president himself, after months laying the groundwork for it?

5. How was the Capitol so vulnerable to attack?

The Capitol is one of the most open complexes in Washington. But Capitol police had upped their security measures ahead of Jan. 6, aware that Trump's "Stop the Steal" rally down the street near the White House could get out of hand.

So how did those protesters march up to the Capitol, overwhelm police, knock down barricades, and take over the House and Senate floors for a time, as well as top lawmakers' offices? Five people died in the Jan. 6 attack or in the immediate aftermath, and 140 police officers were assaulted. The Capitol Police chief resigned a day after the insurrection.

But the committee has debated how much to delve into that question, report The Post's Jacqueline Alemany and Josh Dawsey. Should the focus be on the building or the people who invaded it? "The Capitol didn't attack itself," a spokesman for Cheney told them.

Another aspect of this question is how the military responded. It took about three hours for members of the National Guard to respond, despite the Capitol Police begging for backup.

Congressional investigators have interviewed top Defense Department officials to try to put together a timeline of how and when the military responded to the attack. They also want to know whether Trump loyalists in the department worked to activate martial law during the attack, an idea that was brought to Trump's attention before and after the attack.

An independent review within the Defense Department found that military leaders responded appropriately.

6. What should be done to prevent similar attacks on democracy?

The committee also wants to share policy prescriptions to keep this from ever happening again.

One idea members seem to be coalescing around is reforming the Electoral Count Act, a law dating to the 1880s that governs how Congress approves states' electoral votes. Lawmakers want to make it much harder for members of Congress to challenge states' results and make it crystal clear that the vice president, who presides over the process, can't override the will of voters while counting the votes.

But states, not Congress, control elections. So Congress has limited power to prevent state lawmakers or secretaries of state from overriding the popular vote. Before Trump set his sights on stopping the certification of the vote in Congress, he was pressuring state officials to overturn results in Georgia and Michigan, among others.

The committee has also been looking at how Trump may have abused or considered abusing emergency power laws. These laws could have allowed the military to seize voting machines and require a rerun of the election. Trump also could have declared martial law, imposing curfews and essentially extending his leadership indefinitely.

There's no proof Trump considered declaring martial law. But texts the committee got from Meadows reveal a litany of top Republicans - including lawmakers such as Reps. Marjorie Taylor Greene of Georgia and Jim Jordan of Ohio, and Virginia "Ginni" Thomas, the wife of Supreme Court Justice Clarence Thomas - encouraging him to keep going with his fraud claims or even to declare martial law.

The possibility so spooked the chairman of the Joint Chiefs of Staff, Army Gen. Mark Milley, that he talked with other military leaders about resigning rather than participate in what would have amounted to a coup attempt, Post reporters Carol Leonnig and Philip Rucker wrote in their book "I Alone Can Fix It."

The committee might not delve fully into proposed solutions until September, when it plans to release a report on its findings and hold one final hearing before the midterm elections.