What are the key arguments of Trump’s lawyers ahead of his impeachment trial?

His lawyers have set out a range of legal and factual arguments, in a 78-page memorandum, that they intend to make at trial.

These are the highlights:

– Argument: Trump did not incite the insurrection

Defence lawyers are adamant that Mr Trump did not incite the riot when he addressed a huge crowd of supporters at a rally that preceded it.

They accuse House impeachment managers of cherry-picking Mr Trump’s statements from an hour-long speech by highlighting only those that Democrats see as helpful to their case, pointing out repeatedly that he had told his supporters to “peacefully and patriotically make your voices heard”.

They argue that even the statement that has attracted the most notoriety – “If you don’t fight like hell, you’re not going to have a country anymore” – was figurative in the general context of election security, not an invocation to violence. And they suggest Mr Trump could not have himself incited the riot given the indications law enforcement had before January 6 of the potential for violence that day.

But for Democrats, the focus on those specific statements at the rally ignores the cumulative impact of Mr Trump’s baseless, weeks-long efforts to call into question the results of the presidential election, and his urging of supporters to come to Washington on the day that the Senate was set to certify the results of US President Joe Biden’s victory.

There was no widespread fraud in the election, as Mr Trump claimed falsely over several months and again to his supporters just before the insurrection. Election officials across the country, and even then-attorney general William Barr, contradicted his claims, and dozens of legal challenges to the election put forth by Mr Trump and his allies were dismissed.

– Argument: His speech is protected

Mr Trump’s legal team plans to lean on the US Constitution in multiple ways, including by arguing that Mr Trump enjoyed First Amendment protections in everything he said to his supporters.

“The fatal flaw of the House’s arguments is that it seeks to mete out governmental punishment – impeachment – based on political speech that falls squarely within broad protections of the First Amendment,” the lawyers say.

In a seminal Supreme Court case, Brandenburg v Ohio, the justices held that the government can suppress speech that is designed to produce imminent lawless action and is likely to do so. But Mr Trump’s lawyers say his words at the rally do not come close to meeting that standard.

In their own filing, House Democrats say the First Amendment defence is lacking since Mr Trump was not impeached for expressing an “unpopular political opinion” but rather because he “wilfully incited violent insurrection against the government”.

“Rights of speech and political participation mean little if the President can provoke lawless action if he loses at the polls” the Democrats wrote.

– Argument: The trial itself is unconstitutional

This is disputed among legal scholars, but Mr Trump’s legal team plans to argue that the trial itself is unconstitutional because he is no longer in office. They say the Constitution does not extend the power of impeachment against a “private citizen”.

They insist that conviction at an impeachment trial requires the possibility of removing the defendant from office. Now that Mr Trump is out of the White House, they say, there is no legal basis for such a trial.

Not so, say Democrats, who say there is indeed historical precedent – albeit not for a president – to conduct an impeachment trial for someone no longer in office for acts committed while that person was in office. They argue there is no “January exception” for a president’s final days in office.

Their argument got a boost on Sunday when Charles Cooper, a conservative Washington lawyer with deep ties to the Republican legal community, wrote in a Wall Street Journal opinion piece that a trial of Mr Trump did indeed pass constitutional muster.

– Democrats have their own statements and actions to answer for

Mr Trump’s lawyers signalled that they will look to defend Mr Trump by invoking other examples of what they say is similar political rhetoric from Democrats.

They point to a statement that House speaker Nancy Pelosi made at a 2018 news conference about the Trump administration’s zero tolerance policy on immigration. “I just don’t even know why there aren’t uprisings all over the country. Maybe there will be,” she said.

It is unclear whether making a comparison with a statement like that, which did not result in violent uprisings aimed at the Trump administration, will actually resonate with a Senate audience, especially as Mr Trump’s lawyers try to make the claim that their own client’s words are being taken out of context.

Mr Trump’s speech to supporters came after he falsely claimed for weeks that the election was being stolen from him and pressured state and local officials to change the outcome.

Beyond those statements, the legal filing suggests other Democrats may find themselves name-dropped in unexpected ways during the trial. Mr Trump’s lawyers argue the trial creates a “dangerous slippery slope” for politically charged impeachments. It posits, for instance, that both Mr Biden and Hillary Clinton could be impeached for actions during the Obama administration.

– Due process

Mr Trump’s lawyers resurrect an argument raised during the first impeachment case against him – that House representatives rushed through the process without conducting a full investigation or evaluating all the evidence.

House Democrats note, though, that Mr Trump was invited to give evidence in his own defence and refused. They say they plan to make note of that at trial to support an inference about his guilt.

Allegations of a hurried or incomplete investigation may be difficult to sustain given that the senators themselves bore witness to the insurrection and were in the chamber when the rioters entered the building.