Thank you for joining our live coverage of day one in the second impeachment trial of Donald Trump.

You can keep following the story on our site, here.

Here's a look back at today's key moments:

• The Democrats, led by impeachment manager Jamie Raskin, began by showing a compilation of footage from Trump's rally and the violent riot that followed, arguing the Senate was within its rights to try the former president.
• Raskin also drew on his personal experience during the siege to make an emotional plea to convict the president.
• Trump's defence lawyers argued the proceedings were unconstitutional as Trump is now a private citizen and lacked due process, accusing the Democrats of being politically motivated and spiteful.
• The Senate voted to affirm the trial's constitutionality, with six Republicans agreeing with their Democratic colleagues that the trial should go on.

It all picks back up again tomorrow at 1200 EST (1700 GMT). Our live coverage will begin here at 1100 EST (1600 GMT).

See you then!

Today's writers and editors were Tom Geoghegan, Marianna Brady, Sarah Fowler, Ritu Prasad, Sam Cabral, Tara McKelvey, Anthony Zurcher, Sam Granville, Georgina Rannard, Holly Honderich and Alice Cuddy.

Image source, Getty Images

It's been a long day of impeachment proceedings, but if you haven't had your fill of US politics yet, we understand.

If you want to read more about the Capitol riot, check out these stories:

• Capitol riots: Five takeaways from the arrests
• Did Trump's words at rally incite violence?
• Watch: The terror of being trapped in the US Capitol
• Watch: What the Proud Boys did before Trump's speech

Or are you looking for more on impeachment?

• Watch: Trump's impeachment explained
• Who are the key players?
• Fact-checking the Senate trial
• The plot (and spoilers) of Impeachment II

The storming of the Capitol last month left five people dead, over 100 police officers injured and millions of dollars in damage to the building.

The impeachment trial comes down to this one question: Did Donald Trump incite the insurrection of the Capitol on 6 January?

No matter what the Senate decides, the repercussions of that day tell us a frightening truth about the divided American public.

BBC Newsnight's Gabriel Gatehouse takes a closer look at the movements of far-right extremists on the day of the riot - and how the Proud Boys were already heading to the Capitol before President Trump had even spoken at his rally.

But the vast majority of those arrested for their actions on 6 January did not have affiliations to such groups before the siege.

Experts say that many more Americans have become radicalised since the election and warn that the risk of political violence could grow.

A month-long search for offenders has resulted in charges against a reported 221 people, which you can read about here.

Tara McKelvey
BBC News, Washington

What can be done if Republicans refuse to convict Trump? - Cody, Ohio, USA

Yes. The senators could censure Trump. This would be a formal denunciation and condemnation by the Senate, but holds no real penalties. Still, it would be a defeat for a man who once described himself as the “greatest of all presidents”.

Very little will be remembered from the first day of Trump's impeachment trial, aside from the opening video.

After hours of arguments, the montage of footage from the Capitol riot that Democrats played remains the top search term in the US.

It's garnered praise online, with one lawyer who worked on Trump's first impeachment calling it a "smart" move.

Journalists who covered the proceedings on Tuesday said the acoustics of the Senate amplified the sounds.

"The sounds of the montage seemed to echo a lot more in the chamber, filling it with the screams and yells of the mob," wrote Emily Cochrane. "When the video concluded, it was silent in the chamber."

Reporter James Poniewozik said that it included footage he had not seen before while MSNBC host Tiffany Cross commented on how powerful the montage was.

And others have said it was a sharp reminder of how violent the riot was, with historian at Princeton university Kevin Kruse commenting about how close to danger those inside the Capitol were.

Here's a look at what Republicans are saying about this first day of impeachment proceedings.

Texas Senator John Cornyn told NBC he was not impressed by the Trump defence team.

"The president’s lawyer just rambled on and on," Cornyn said. "I’ve seen a lot of lawyers and a lot of arguments and that was not one of the finest I’ve seen."

But Alabama Congressman Mo Brooks continued to back the president (he was among the lawmakers to dispute the election results last month).

"Impeaching Donald Trump for inciting a riot is akin to impeaching him for Russian collusion – neither of which happened and both of which are Socialist Democrat concoctions," he tweeted.

A Trump campaign account, meanwhile, tweeted a criticism of having Democrat Patrick Leahy chair the session. (Typically ensuring trial rules are followed is the job of the Chief Supreme Court Justice, but he declined.)

"Imagine having a 'trial' where the 'judge' had already voted to convict the defendant? That's what happens in banana republics, third world dictatorships and now the United States Senate. SAD!"

Conservative pundit Ann Coulter shared an opinion piece from political news site The Hill that suggested Republicans could unite the country by convicting Trump, commenting: "And Democrats could unite the nation by giving them a wall in return!"

Rab is a doctor who has been very frustrated with Trump over the past four years and says his irresponsible conduct since the election merits his impeachment. He is a member of our voter panel.

Do you think Donald Trump should be convicted by the Senate?

Yes. Even before the violence at the Capitol, he made comments calling people to come to DC on 6 January and "stop the steal". When the president of the United States says something, people believe it.

He also made comments encouraging people to fight like hell and scared them that they wouldn't have a country anymore if they didn't.

We need to hold people accountable for doing things that are wrong.

Six Republican senators just joined their Democratic colleagues in voting to move the trial forward.

They are Lisa Murkowski of Alaska, Bill Cassidy of Louisiana, Susan Collins of Maine, Ben Sasse of Nebraska, Pat Toomey of Pennsylvania and Mitt Romney of Utah.

You may have heard most of those names before - Murkowski, Collins, Sasse, Toomey and Romney had previously taken a similar vote upholding the constitutionality of the trial proceedings.

But Bill Cassidy is a noteworthy name on the list: he had previously voted to dismiss the trial.

Cassidy later told CNN the House prosecutors made "very good arguments", noting he'd always planned to approach the trial "with an open mind" and as an "impartial juror".

Anthony Zurcher
BBC North America reporter

Well, that should about do it. There are going to be four days of arguments, Senate questions and, perhaps, witnesses.

The final outcome, however, is all but certain.

When the first substantive vote of the impeachment trial was taken on Tuesday – a vote about whether to have a trial at all – only six Republicans sided with all 50 Democrats to proceed.

That’s well short of the 17 Republicans who would be necessary to convict.

And if there aren’t 17 Republicans who think there should be a trial at all, it seems unlikely that the House impeachment managers are going to be able to change enough minds.

Sam voted twice for Donald Trump but has turned his back on him, saying the attack on the Capitol "made me sick to my stomach". He is a member of our voter panel.

Do you think Donald Trump should be convicted by the Senate?

There is not enough direct correlation and evidence for him to be convicted, so he should not be. But the impeachment in the House was a good slap on the wrist. There needed to be some sort of response to the way he handled - or didn’t handle - the peaceful transfer of power.

I don't think Trump himself was directly responsible for getting people riled up but I do think that he set the stage for what happened.

But pursuing a conviction is just another means of tribalistic partisan politics that will further divide the country because there are still millions of Americans who voted for Trump and really like him.

Alright, so in the last four hours, we've heard from House prosecutors and the Trump defence team.

And we've just had a speedy vote on whether or not the trial is constitutional and can continue (it is, and it will).

Now what?

• Starting tomorrow at 1200EST (1700GMT), each side will have 16 hours to present their case.
• Each side cannot exceed eight hours of presentation each day and cannot exceed two days of presentation overall.
• After that, the Senate will have a total of four hours to question both sides.
• If the prosecutors choose to call witnesses or request more documents, each side can then have four hours to make their case.
• The two parties will then have a total of four hours to make their closing arguments.

Both Republicans and Democrats are keen on a speedy trial, US media report, so we could see a vote on conviction as early as this weekend if there are no witnesses to hear from.

The Senate has voted 56-44 that it is constitutional to hold a trial for a president who is no longer in office.

This means Donald Trump's second impeachment trial will continue, starting tomorrow.

Only a simple majority was required on the measure.

Now that arguments from both sides have concluded, the Senate is voting on whether or not to go forward with Trump's impeachment trial.

BBC editors in Washington have cast a critical eye on how well the defence lawyers are making their case.

Samantha Granville
BBC News, Capitol Hill

There is only one camera in the Senate chambers and it's not on the senators. Here's what's going on that you can't see.

Republican Senators Murkowski, Collins and Graham are the studious notetakers.

Senator Josh Hawley, also a Republican, was reading papers that didn’t seem to be marked with the symbols of the House - so they probably weren't trial-related documents.

Senator Sasse looked confused at one point and seemed to just shake his head before sharing a whisper with Senators Scott, Burr and Portman.

Democratic Senator Sanders is staring straight ahead and listening to the arguments.

Fellow Democrat Senator Booker is in the back of the room. He appeared to get a little restless and stood up and leaned against the back wall of the chamber.

The former president's lawyers continue their arguments that the impeachment trial is unconstitutional.

Later tonight, the Senate will hold a vote on whether or not the trial can take place.

Here are some of defence attorney David Schoen's arguments:

• He says Democrats are using "the guise of impeachment as a tool to disenfranchise" those who support Donald Trump.
• He argues that Democrats have had an "insatiable lust for impeachment in the House for the past four years", referring to it as an "unprecedented snap" trial with little due process.
• He played a video that showed various Democratic members of Congress calling for the former president's impeachment, including several videos from 2017, his first year in office.
• He also referenced House Speaker Nancy Pelosi's "politically motivated threat" that the lower chamber would impeach Trump if Vice-President Mike Pence and his cabinet did not invoke the 25th Amendment to remove him from office.

Tara McKelvey
BBC News, Washington

Image source, Getty Images

Trump is facing legal troubles in Washington, and at home in Palm Beach, Florida, too.

He bought his ocean-side property, an estate called Mar-a-Lago, in 1985, and spent part of his winters there. Then, after leaving the White House, he moved in.

Some of his neighbours want him out, saying he will bring down property values, and have talked about evicting him. They say an agreement that was reached nearly 30 years ago, one that turned the estate into a private club, does not allow anyone to live there on a permanent basis unless they work on the premises.

Trump, through a lawyer, has argued that he should be allowed to stay, as an employee. The issue is being discussed at a Palm Beach Town Council meeting on Tuesday.

One of his former employees, Wes Blackman, a former project director at Mar-a-Lago, says that Trump will see the designation as an employee not as a demotion, but as an opportunity, a loophole that will allow him to stay where he is. The designation as an employee is "convenient and expedient", says Blackman.

"It gets him out of a tight situation." Besides, says Blackman, the fight with his neighbours in Florida is not the biggest problem Trump is facing today. Over the course of the day, Blackman has been watching the impeachment trial in Washington, wondering how his old boss will fare.

Image source, Getty Images

Now up, Trump lawyer David Schoen.

He begins by saying it's an honour to appear in this chamber, but "that is tempered by a feeling of grave concern".

"My overriding emotion is frankly wanting to cry for what I believe these proceedings will do to our great long-enduring Constitution and to the American people on both sides of the great divide that now characterises our nation."

Schoen says the trial is unconstitutional and "wrong as wrong can be".

He adds that while Democrats claim the proceedings are for accountability if that was the case, they would wait for a full investigation.

He says the trial is a "chance for partisan politicians to eliminate Donald Trump from the American political scheme and to disenfranchise" the millions of people who voted for him.

Schoen says the trial is for "pure, raw, misguided partisanship".

Much of Trump lawyer Castor's speech has focused on appealing to the patriotism of the Senate.

"The top responsibility of a US senator and the top characteristic that you all have in common... there isn't a single one of you who doesn't consider yourself a patriot of the US."

"That is why this attack on the constitution will not prevail," he says, reiterating his argument that the impeachment of Trump is unconstitutional.

Image source, Reuters

Trump attorney, Bruce Castor Jr, denounces the Capitol riot and says those responsible ought to be prosecuted.

He adds that there is a reasonable desire to ask "how do we make them pay?"

But Castor argues that Trump should not be the scapegoat for this tragedy.

"We expect US senators to not react to popular will and emotions, but do what is right," Castor says.