For the next month or so, MPs are going to be debating, scrutinising and voting on one of the most important pieces of legislation ever put before Parliament.
The stakes are high, as Theresa May’s has a working majority of just 13 - although with ‘Labour Leave’ MPs that rises to nearly 25 on Brexit matters.
Even with the backing of anti-EU Labour MPs, it is still going to be a nervous few weeks for the Government as it tries to steer its flagship Bill through the Commons.
Here’s what you need to know about the EU Withdrawal Bill.
Why is it needed?
As everyone knows, the UK voted to leave the EU in a referendum in 2016.
But it isn’t the case the UK can just drop its EU membership card off at the reception in Brussels, hope on the Eurostar and come home.
As well as negotiating with the EU over the terms of our departure, the UK also needs to get its own house in order.
Firstly, it needs to repeal the law that took us into the EU – or the EEC as it then was – in 1972: The European Communities Act.
Secondly, the Government needs to copy over 40 years of EU law to make sure the everything continues as it currently does the day after Brexit. It is after this that MPs will be able to pick and choose which EU derived laws they wish to change or scrap entirely.
Thirdly, the Government says that in copying over that law, there may need to make some changes in to ensure they work properly. But instead of coming to Parliament to get MPs approval every time a change is needed, the Government wants to give itself extra powers to allow ministers to make alterations.
Want to know what’s really going on with Brexit? Sign up for HuffPost UK’s Brexit Briefing - sent straight to your inbox every Thursday.
The Key Controversies
Henry VIII Powers
One of the key controversies is around the powers the Government wants to give itself – the so-called Henry VIII powers.
The Bill will give Ministers the power to do anything which MPs can do when it comes to passing an Act of Parliament. This means the legislative authority of the Commons will be transferred to the signature of a Government minister.
The only exceptions set out in the Bill are to do with taxes, creating new criminal offences and anything to do with the Human Rights Act.
But in reality, ministers could give themselves the power to do all of those things – as under the terms of the Act they are able to change the very Act itself.
CHANCES OF DEFEAT: 4/5
Another worrying aspect of the Bill is the “sunset clause”. This is supposed to make sure all these powers end two years after the “exit day”.
Originally, the Bill did not contain a definition of “exit day”, meaning it would up to the Government to define when the UK had sufficiently left the EU to give up its powers.
After pressure from MPs, the Government announced las week the exit day will be written into the law as March 29 2019. However, as the Henry VIII powers show, this could be changed at any moment by the Government.
CHANCES OF DEFEAT: 2/5
Vote On The Final Deal
Another area where the Government has already conceded is on the final Brexit deal itself. David Davis announced on Monday that MPs would now get a vote on the deal as primary legislation – meaning it can be amended.
However, there is no guarantee that vote will take place before the UK leaves the EU, and if MPs reject the deal then Britain will leave on World Trade Organisation terms – often dubbed a ‘hard Brexit’.
One anti-Brexit Labour MP attacked this concession as a “sham”, and Tory MP Dominic Grieve, who put forward an amendment to get a more meaningful vote, seemed unimpressed by the announcement.
Professor Catherine Barnard, senior fellow The UK in a Changing Europe, said that Davis’ promise on the final deal “was presented as a classic Hobson’s choice: either accept it (‘deal’) or reject it (‘no deal’).”
She added: “In the event of no deal, this will result in a chaotic Brexit. This is where the EU Withdrawal Bill will come into its own, providing some legal certainty for EU citizens and businesses.”
CHANCES OF DEFEAT: 3/5
There are an estimated 111 laws set to come back from Brussels which are technically areas for the UK’s devolved bodies. The EU Withdrawal Bill would see those powers return to Whitehall, but not automatically passed on to Scotland, Wales and Northern Ireland.
The Scottish National Party are predictably up in arms about the move, but pressure on Theresa May to change the Bill is also coming from colleagues on her own benches from north of the border.
MSP Adam Tomkins, a close ally of Scottish Tory leader Ruth Davidson, last week called for the vast majority of laws be transferred directly to Holyrood.
Dr Jo Hunt, senior fellow The UK in a Changing Europe, said: “The Withdrawal Bill has significant consequences for devolution and the balance of powers between London and the devolved nations.
“It has aroused considerable opposition from the Welsh and Scottish governments and elected representatives.
“Without fundamental change to the devolution aspects of the Bill, it will face being rejected by the devolved parliaments, creating profound constitutional tensions.”
CHANCES OF DEFEAT: 2/5