Reality Check

One of the topics being discussed in tonight’s presidential debate is the issue of violent crime. President Trump says there’s been a major spike in crime this year and that he’s the best candidate to tackle it.

We’ve looked into rates of violent crime in the US, and found that in many US cities it has fallen compared to the same period last year.

It’s a downward trend stretching back over many decades, as shown in this chart of violent crimes recorded in two of the worst affected cities, New York and Chicago:

However, Mr Trump does have a point if looking at just murder rates, which have shown significant rises in major US cities like Chicago over the past year.

Image source, Getty Images

It's less than 1.5 hours until Donald John Trump and Joseph Robinette Biden Jr. take to the stage.

Observers are primed for a fierce, perhaps rancorous, debate expected to draw tens of millions of viewers - although the studio audience will be limited due to social distancing.

With Trump behind in the polls, his challenger is expected to pounce on revelations about the president's income tax payments - including that he paid just $750 in 2016 and 2017.

Aiming to rattle his opponent, Biden released his own tax returns just a few hours ago. He and his wife Jill paid nearly $288,000 (£224,000) in income tax last year, according to the filings, external.

President Trump is skilled at deflection, but will he manage to divert attention from his record during the coronavirus pandemic with claims about Biden's son Hunter, and his dealings in Ukraine?

Can Biden, who has demonstrated flashes of hot-headedness during the campaign, keep his temper under 90 minutes of goading?

It's going to be a fascinating watch!

Laura Trevelyan
BBC World News America presenter, Cleveland, Ohio

Image source, Getty Images

Just 6% of those polled by CBS News say they are watching tonight’s debate to decide who they’ll vote for.

Much of the country has already decided, and will be tuning in tonight to cheer on their man. Indeed, millions of Americans have already requested absentee ballots and more than 1.2 million have cast their ballots.

For the undecided voters, first impressions are likely to be crucial - which makes the opening 30 minutes absolutely key. The challenge for Donald Trump, who is looking to reset the race, is to attack and put Joe Biden on the back foot.

The former vice-president has successfully run a mostly virtual campaign so far. Tonight, supporters predict, he’ll try to deflect personal attacks about him and his son Hunter by saying "let’s not talk about my family, let’s talk about what we can do for the American family".

When he formally announced his entry into the 2020 presidential race, Joe Biden declared that he stood for two things - workers who "built this country", and values that can bridge its divisions.

As the US faces challenges from coronavirus to racial inequity, his pitch in essence is to create new economic opportunities for workers, restore environmental protections and healthcare rights, and international alliances.

Here's our look at where he stands on the key issues.

One of the topics we'll hear the candidates debate tonight is the Supreme Court.

The nation's highest court is a contentious subject for many, as it gets the last say on many hot-button issues (think abortion access, gun rights, healthcare, and immigration).

Under President Trump, the court has been called the most conservative-leaning in modern US history.

Now, the death of liberal justice Ruth Bader Ginsburg means it could further tilt towards the right if Trump and the Republican-controlled Senate are able to replace her in the months ahead.

With two appointments already in the president's first term, the bench's ideological balance favours conservatives in a 5-4 split.

So how much has the Trump-era Supreme Court changed America's legal landscape? We look back at five closely watched cases from the last year - with some help from our North America reporter, Anthony Zurcher.

Read the full analysis here.

Laura Trevelyan
BBC World News America presenter, Cleveland, Ohio

Congressman Tim Ryan of Ohio will be in the debate hall tonight supporting Joe Biden - he tells me this bellwether state of Ohio, comfortably won by Donald Trump in 2016, is going blue and I can "take that to the bank".

The suburbs are trending Democratic, says Congressman Ryan, as people turned off by the chaos of the Trump presidency and his handling of the coronavirus turn towards Joe Biden.

Everyone wants to know - who are Americans going to vote for?

Although many have made up their minds on how they will vote in November, others remain unconvinced and need to hear more from Trump and Biden.

Tonight, we're watching the debate with four members of our US election voter panel – one Biden voter, one Trump voter and two undecided voters.

Learn about Ariel, Joshua, Brian and Keirsten.

If you're a US voter, you can join our panel for future debates here.

We've been asking readers what they'd ask Biden and Trump if they could sit in the moderator's chair for the evening. Here's a look at what people around the world had to say.

• What is Trump's stance on global warming? - Juliette, 16, France
• Is the current US schooling system permitting children from all social classes to receive a high-quality education? - Edouard, 16, Switzerland
• What would you say to families who have lost loved ones to the Covid-19 pandemic? - Donna, 48, Memphis, Tennessee, US
• If you were to make one major concession to the other side, would it be a Supreme Court nomination, the Affordable Care Act (Obamacare), or immigration policy? - Labib, 56, UK
• After four years of lines being drawn, how does each candidate propose to unite the United States? - Gretchen, 46, Albuquerque, New Mexico, US

We'll share more thoughts from our audience throughout the night.

You can submit your own queries here - about the debate or anything US election-related - and we'll get our reporters on it.

While Trump is spending the remaining hours before the debate in a hotel near the debate venue, Biden is staying at a private house about 25 minutes away in Pepper Pike - a suburb of Cleveland.

The Biden campaign won't say whose home it is. While there, Biden has apparently decided to step out for some old-fashioned campaigning.

As Donald Trump eyes a second term in office, he faces a country struggling with challenges from coronavirus and the pandemic's economic aftershocks - and an electorate that will weigh his record from his four years in office.

His 2020 pitch is to bring back the economy, boost jobs, protect US trade interests, and to continue with his hard-line stance on immigration.

We looked in detail at where he stands on eight key topics: Jobs and money; trade; foreign policy; immigration; health; climate change; criminal justice; and gun control

What are Donald Trump's policies?

Emily Maitlis
Newsnight Presenter

Joe Biden goes into this debate with a substantial lead in the national polls. So this debate becomes a chance to reset the race if Donald Trump gets it right.

And I imagine he will want to set traps for the Democratic nominee.

Don't forget that Biden has up till now united a party which had been quite divided. He’s brought the progressives on side - the Bernie Sanders wing - and he’s brought the centrists from the Obama era with him.

But what happens when he’s asked about wedge issues that could divide these two sides?

How does he answer, for example, a question about reparations for slavery - which some on the left of the party have advocated.

What if he’s asked about a move to expand the Supreme Court - "court packing" - which could even up the political balance.

Again it’s a move favoured by a segment of the Democratic base, but one that could hugely alienate the centrists who perhaps want a candidate to steady the ship, not create revolution.

These are going to be the tough balances for Biden tonight. On the other hand, Trump has made life easier for his rival by downplaying expectations.

Continued references to Biden’s "medication","weakness", insinuations of "dementia" could mean that all Biden has to do is not fall off the stage - and he will be seen to have triumphed.

Ritu Prasad
BBC News writer, Fort Myers, Florida

We’ve been asking our readers for their most pressing questions about the US election. Now it’s our turn to respond.

Click here if you want to know more, or to send us a question of your own.

Lee R, 48, from Peoria, Arizona, asks: I have voted by mail in Arizona, how does that compare with states that just started sending out ballots to registered voters? What security measures do they have?

We’ve gotten quite a few questions on election security and mail-in ballots, so here’s a (very general) look at how states keep absentee voting secure.

According to the National Conference of State Legislatures, external, along with Arizona, 30 states verify signatures on ballots with what’s in a voter’s file - these include California, New York, Texas and Florida. Only six don’t verify a signature.

In eight states, voters need witness signatures, or a notary, in addition to their own.

Mississippi, Missouri and Oklahoma go further and say absentee voters must have the ballot notarised. In Arkansas and Alabama, voters must also mail in a copy of their ID.

Many states begin processing absentee votes before Election Day - 3 November 2020 - to get a head start on verification.

But with millions more opting to post their votes thanks to Covid-19, we’re not really sure what election night (or week, or month) might look like.

We explored what could happen here.

For more on postal voting, check out our Reality Check team's explainer on voting fraud.

Laura Trevelyan
BBC World News America presenter, Cleveland, Ohio

Donald Trump Jr is doing the rounds of TV positions outside the debate hall. He says his father has been treated very unfairly by the New York Times, and one thing the tax records showed was that there’s no financial connection between the president and Russia, but the media isn’t interested.

He says his father will talk about his great record of achievement tonight - the trade deals he’s done for the American worker, standing up to China.

As someone who travels the battleground states campaigning for the president, Don Jr says there’s tremendous support for Trump. Joe Biden has been in public life for 47 years and his record is nothing compared to Trump’s, says the loyal son.

We're waiting for what promises to be an electrifying evening, but let's not forget what it's all leading up to - the election on 3 November. One question we get asked a lot has to do with the fact that the president of the United States isn’t directly elected by American voters but by members of what's known as the electoral college. Here’s how the system works.

Reality Check

Mr Trump has repeatedly said he’s not allowed to make his taxes public while an audit is taking place, but that he would make a disclosure once it had been completed.

Mr Trump’s legal team says his tax returns since 2009 are still in the process of being audited by the US tax authorities.

There is, however, no legal reason why the president can’t release his returns during an audit as we explain in our fact-check on the subject, and he is the first in almost 50 years not to make them available.

It’s also not unusual for US presidents to have their finances audited whilst in office.

According information published by the New York Times this week, President Trump paid just $750 in income tax in both 2016 and 2017.

Joe Biden has just taken a tour of the debate hall, and in contrast to Trump, has chosen to wear a mask while on stage.

Biden has rarely left his home in Delaware, and has limited his physical campaigning due to the coronavirus pandemic. Winning Ohio is crucial to his campaign - the state is seen as a bellwether for the outcome of the election.

Biden is keen to make tonight's debate a referendum on Trump's handling of the virus, and to show Americans that he is better suited to handle the pandemic that has claimed over 200,000 lives and derailed the economy.

Later tonight, neither candidate will be required to wear a mask on stage. But there's a decent chance Biden will wear one anyway as he walks to his podium, just to send a message to voters.

Image source, Getty Images

Who's in the best position as we wait for crunch time, Trump or Biden?

Philippe Reines, formerly a senior adviser to Hillary Clinton, played Donald Trump during her 2016 debate prep - and he believes Biden's got the advantage.

Why? "Because people see Donald Trump every day. If that guy shows up tonight, why are they going to like him any more at 9 o'clock tonight than at 2 o'clock in the afternoon? They're not!"

Ritu Prasad
BBC News writer, Fort Myers, Florida

We’ve been asking our readers for their most pressing questions about the US election. Now it’s our turn to respond. Click here if you want to know more, or to send us a question of your own.

Noel E, 64, from Herefordshire, UK, asks: How will the thousands of fire-displaced Americans get to vote?

Great question - and a timely one as state registration deadlines are fast approaching.

To vote in the US, you need to provide a mailing address and a residential address when you register.

When you request an absentee ballot, it’ll arrive at whatever you list as your mailing address - like a family member’s house, a PO box, a local election office, a shelter - even if you don’t normally live there.

But you’ll need to make any address changes soon.

For California, the online registration deadline is 19 October, and if you miss it, you’ll have to go to a voting site or pick up a ballot at an office. For Oregon, you have until 13 October, and 26 October in Washington State.

The presidential debates are a pretty big hitter, ratings-wise.

The lowest viewership ever recorded was a mere 36.1 million in 1996, when Bill Clinton (the incumbent president) took on Republican Bob Dole.

The highest rated appearance? President Trump would doubtless be pleased to know it was his: The first debate between Trump and Hillary Clinton drew 84 million viewers in 2016.

Image source, AFP PHOTO / Robyn Beck

Those with long memories may recall the Democratic nominee asked the now-president about his taxes, suggesting he had paid no federal tax in recent years.

“That makes me smart,” Trump responded.

It’ll be interesting to see how he addresses the issue tonight – because you can guarantee it’s coming up.

Image source, Reuters

Tonight's debate will be on air at the same time as a baseball game between the Cleveland Indians and the New York Yankees on ESPN. So who usually wins when politics and sports compete in the ratings war?

During the 2016 election, an American football game between the Atlanta Falcons and New Orleans Saints was scheduled for the same time as one of the presidential debates - and ended up with the lowest ratings in the history of Monday Night Football.

Other prime time events are taking place this week, but won't be coinciding with the debate: the final of ice hockey's Stanley Cup was held last night and the NBA Finals begin tomorrow night.