The need for a Brexit ‘backstop’ – to prevent a hard border between Northern Ireland and the Republic – was one of the first things both the EU and UK agreed was essential in negotiations. But after negotiations faltered time and again over the details of the backstop, the complexity of this contentious issue became ever more evident. Now, with a deal thrashed out, the backstop is still posing the biggest threat to Theresa May and her ability to get the deal passed through UK Parliament.
Before we delve into the topic, it’s important to remember two things: Firstly, if the Brexit deal is voted through on December 11, this doesn’t mean negotiations are done.
All that really does is reset the clock to allow more time for the nitty gritty details of a deal to be finalised, which will be done during the two-year transition period after the March 29 official Brexit deadline.
Secondly, we need to remember that the backstop, according to the Government, is a “last resort,” is not desirable, and will ONLY be enforced if a better solution has not presented itself during the two years of transition.
READ MORE: A Brexit timeline – from the referendum to today and what’s up next
Brexit backstop explained: The issue of the backstop and the Northern Ireland border are complex
Ok then, so what is the backstop in simple terms?
The backstop is a sort of safety net or insurance policy.
The backstop is meant to ensure no matter what happens with the rest of the negotiations, there won’t be a hard border between Northern Ireland and the Republic.
So, even if the rest of the UK leaves the EU with no trade or security arrangements, there won’t suddenly be border checks and restrictions on the island of Ireland.
At present, goods and services are traded between the two jurisdictions with few restrictions.
As the UK and Ireland are currently part of the EU single market and customs union, products do not need to be inspected for customs and standards, but after Brexit, all that could change.
Brexit backstop explained: The backstop is a sort of safety net or insurance policy.
Why is the backstop so tricky?
The two main spheres of sensitivity around the backstop can be broken into two main themes: political and economic.
The basic building block of peace in Northern Ireland – the 1998 Good Friday Agreement – removed security checkpoints from the Irish border and made it practically invisible.
Before this agreement, a long period of conflict, had run since the 1920s, known in the latter half of the 20th century as The Troubles.
The Troubles was a period of violence between two groups – Republicans (who wanted Northern Ireland to re-join the Republic) and Loyalists (who wanted to remain part of the UK). Many people were killed in the fighting.
There are concerns that a return to a hard border could reignite the political violence of The Troubles.
In addition to this, and creating a catch-22, is the worry of creating a hard border down the Irish sea – cutting off Northern Ireland from the rest of the UK.
Essentially, if the Irish border remains fluid, there would still need to be checks in place for goods in and out of the rest of the UK and EU.
If there is no hard border in Ireland, those goods will need to be checked in ports, meaning trade between Northern Ireland and the rest of the UK would be stilted.
So a hard border in Ireland won’t work, and a border in the Irish sea won’t work.
And why do we need to have a border of some sorts? Because the UK has insisted it will leave the EU single market and customs union.
That means, somehow, everything in and out of the UK to and from the EU needs to go through a border check.
READ MORE: Follow our LIVE updates as Brexit debates unfold
Brexit backstop explained: There are political and economic sensitivities around the Irish border
The other concern, of course, is economic.
The economies of Northern Ireland and the Republic are completely interconnected.
Huge amounts of goods and services cross the border every day without checks of any kind.
At least 30,000 people are estimated to travel across the border each day for work.
The Republic and Northern Ireland have a Common Travel Area which predates the EU, which both sides insist will stay in place regardless.
But this doesn’t prevent a hard border emerging for everything else.
READ MORE: How healthcare and the NHS will suffer, deal or no deal
Brexit backstop explained: The main motorway between Northern Ireland and the Republic
So what does Theresa May’s deal say about the backstop?
After months on end of negotiating, Theresa May finally announced her deal on November 14 – but as we’ve seen, there aren’t many in British politics who are willing to support it.
The deal includes a backstop that would see Northern Ireland staying aligned to some rules of the EU single market, if another solution cannot be reached before the end of the transition period (end of 2020).
That means that goods coming into Northern Ireland from the rest of the UK would need to be checked to see if they meet EU standards (essentially creating a border between the two).
It would also involve a temporary single customs territory effectively keeping the whole of the UK in the EU customs union – until both the EU and UK agree that it is no longer necessary.
But the worry here is that the UK would not be able to leave the backstop unilaterally – meaning the EU would need to approve the backstop ending.
This could lead to the UK being required to follow EU rules for an indefinite amount of time, while holding no say in them due to the leaving status.
Mrs May has said there was no deal on the table that did not involve signing up to the backstop – but that it is only an insurance policy.