• That was an interesting if, at times to the layman at least, an occasionally impenetrable opening. What have we learnt so far?
• The court will make its decision based on the legal principles only, putting to one side the political questions surrounding Brexit, President Lord Neuberger said in his opening remarks
• He added that some participants had received “threats of serious violence and unpleasant abuse” on social media simply for exercising their “fundamental right” to go to court. This abuse, he argues, “undermines the rule of law”
• Opening for the government, Attorney General Jeremy Wright said the result of the EU referendum was "clear" but the court had a right to decide what role Parliament had to play in the Brexit process
• Parliament had the ability to "stand up for itself" and curb the government's prerogative powers but had chosen not to do so, he insisted
• The use of executive powers to begin Brexit talks was not only lawful but in "line with parliamentary sovereignty and in accordance with legitimate public expectations", he told the court. 
• Jeremy Wright said prerogative power has been "deliberately and definitively" granted to governments
• James Eadie QC says the way EU treaty became law shows government can create or remove rights through international deals
• The case is expected to last four days with a decision in January  

James Landale
Diplomatic correspondent

The government has announced it will try to keep existing EU tariff rates on goods entering Britain from outside the EU, after it has left the European Union. 

In a written statement, the international trade secretary Liam Fox said he wanted to "replicate as far as possible our current obligations" which have been agreed at an EU level. 

He said he would draft new UK-specific "schedules" at the World Trade Organisation that would be similar to existing tariff and quota rates in order to "minimise disruption to global trade". 

He made the announcement as a formal dialogue with the WTO began about Britain's trading relations after Brexit. 

Mr Fox said: "The UK’s WTO commitments currently form part of the European Union’s schedules. When we leave the EU we will need UK-specific schedules. In order to minimise disruption to global trade as we leave the EU, over the coming period the Government will prepare the necessary draft schedules which replicate as far as possible our current obligations."

Lord Sumption presses Mr Eadie at length about the basic rationale and purpose of the royal prerogative, which makes for an interesting exchange. 

Mr Eadie hints about a "short adjournment" being in the offing and just as he is about the launch into a discourse of the "principle of legality" - Lord Neuberger intervenes and asks whether it would be a "good moment" for lunch.

The whole court seems to be in agreement and proceedings come to a halt - to be resumed at 1400 BST.

The focus moves on to another historical case relating to the use of the royal prerogative. 

This was the dispute in the 1970s between the government and the famous airline entrepreneur Sir Freddie Laker about whether he should be granted a licence for a budget airline between the UK and United States - which at the time was seen as a serious threat to British Airways and other trans-Atlantic operators. 

After years of wrangling, the Skytrain service launched between Gatwick and New York in 1977 but the business went bust five years later. 

Lord Mance takes a particular interest in this and pursues a line of questioning about the case and the degree to which the use of the prerogative was underpinned by legislation in place at the time or flouted it.

Nadine Dorries has said she doesn't think the court case should even be going ahead. 

The Conservative MP told the Daily Politics: "People put their trust in the Government when they put their tick [in the box] and the argument was made clear that this is what it is going to look like. People knew exactly what they were voting for."

We have been going for about 90 minutes now. 

Mr Eadie runs through a number of relevant cases from the past relating to executive powers, including one revolving around the government's seizure of a hotel during World War One for use as a munitions plant.

He says the De Keyser Hotel ruling from 1920 - which stated the government could not use prerogative powers to pay its owners lower levels of compensation - had been superceded since by other judgements. 

As a result, he says it is necessary to reverse the "conventional approach" to how the extent of government powers are viewed.

The Daily Politics

A cheerful update from our man at the court on the Daily Politics.

"If it was highly charged outside... inside, OJ Simpson it is not,'" said political correspondent Rob Watson. "It is pretty dry stuff."

For those too young to remember, that's a reference to the US televised murder trial of sports star OJ Simpson back in the mid-1990s. That was a trial which was this year turned into a hit drama-documentary, starring John Travolta amongst others.

Will we be seeing a prime time dramatisation of this week's events in 20 years time? Tune back in here, in 2036, to find out...

An Andrew Marr interview with Marine Le Pen on Remembrance Sunday "was justified", Ofcom rules.

More to and fro on the applicability of prerogative powers to Article 50 and whether it is out of step with domestic legislative precedents. 

Putting the government case, Mr Eadie says legislation enshrining rights derived from EU membership into domestic law was "susceptible to change" and governments can "entirely lawfully take steps without further parliamentary authorisation which directly alter domestic law, including by removing rights".

He is taking on the argument from Ms Miller's team that rights conferred and created by Parliament - including those in the 1972 European Communities Act - can only be taken away by Parliament.

Interestingly, he cites Greenland's departure from the European Community - in the mid 1980s - saying changes to rights through treaty agreements at the time were implemented via prerogative powers rather than primary legislation. 

Wales Online

Mick Antoniw, Counsel General for Wales and Pontyprid MP, said there were fears for his country if Brexit goes the wrong way. 

He told Wales Online, external: “People did not vote to allow the UK Government to use Brexit as a means of rolling-back devolution by returning to Westminster control over our farming and agriculture industries, our environment, our fisheries and other matters that have been devolved to Wales since 1999.

“The sole legal question before the Supreme Court is simple – can the UK Government, as a matter of constitutional law, withdraw the UK from the EU without an Act of Parliament providing prior authorisation to do so? The view of the High Court is that it cannot.

“Our view as a Welsh Government is that it cannot. The UK Government want to use the Crown Prerogative to invoke Article 50 of the Treaty on European Union, but they don’t want the UK Parliament to have that say.”

Some brief jollity over the mass of bundles of case law at the court's disposal and whether Mr Eadie is directing the justices to the right document. 

Mr Eadie says he is "testing the (IT) system to the point of destruction" to which Lady Hale, who has already picked Mr Eadie up at one point, tells him "I am sure you are right".

Lord Neuberger intervenes to tell Mr Eadie he is right but adds the little rejoinder "on this point" - which leads to an outbreak of laughter in the courtroom.

We are beginning to get interventions from some of the justices. 

Lord Carnwath asks government lawyer James Eadie whether he believes that the use of executive powers should be subject to legal review from time to time.

"When deciding what difference the referendum makes, then arguably if the government said 'we are going to get out of Europe without any parliamentary mandate at all or in the face of an adverse referendum, that may be said to be an abuse of power which is reviewable by the court on that basis," he says.

He suggests it is a point which the government's legal team might like to return to at some point over the next four days. 

In a roundabout way, Mr Eadie seems to defer to him on this point - saying there are "non-justiciability" issues to consider. 

We weren't the only ones who noticed... 

Jeremy Wright hands over to senior government lawyer Mr James Eadie. 

He continues on a similar theme, elaborating on the government's executive powers which he says are a vital pillar of the "modern British constitution" - used by successive government in matters of war and peace and international relations.

He says his arguments are complex and necessarily longer than they would be in other cases. But he says he is conscious of those watching proceedings outside the court and clearly speaking as a horseracing fan, he understands his responsibility to keep the "broader interest" on board during what is bound to be an avalanche of legal arcana.

Courtesy of the TV cameras we have had a good look around the inside of the courtroom, and it does not look like the most diverse crowd...

Concluding his remarks for the time being, Attorney General Jeremy Wright, for the government, says for all the reasons that he has set out, to deny the government the right to use prerogative powers to trigger Brexit talks would not be "supportive of parliamentary sovereignty but would be positively inconsistent with it". 

The Daily Politics