William Hague:

Boris is prepared to give ground to the EU because otherwise MPS will vote to delay Brexit indefinitely

Last week I described why each of the three key decision-makers in the latest Brexit negotiations – Boris Johnson, the Democratic Unionist Party and the Irish Prime Minister, Leo Varadkar – has a strong incentive to do a deal. Since then they have all duly demonstrated that they want to do one, despite optimism waxing and waning every few hours after each bulletin from Brussels.

Yet some people in this country will be puzzled as to why the great majority of concessions seem to come from the British side, and why the “do or die” Prime Minister continues to make them. The UK has conceded that the island of Ireland will be one area for the purposes of regulations covering agricultural and manufactured goods and has, as far as one can tell, also accepted that any departure from that regime would require the consent of both nationalists and unionists in Northern Ireland.

On the third and most complex issue of customs rules, it is again the British Government that is giving ground from its initial position, although any solution will involve the EU and Ireland accepting some new way of managing customs, previously unknown in the world.

A deal might be done but, if so, it will be one that stretches the tolerance of hardline Brexiteers to the limit. Why is this ebullient and determined PM, the champion of leaving come what may, so utterly devoted to doing that deal, even if more concessions are made along the way?

Part of the answer lies in the briefings he will have received about the inevitable consequences of a no-deal departure. While much attention is understandably focused on the fate of industries such as car manufacturing, Boris will have read and digested a stream of advice pointing out the serious risks of instability in Northern Ireland and also of losing access to vital databases of criminals and potential terrorists. No sane person could sit in Downing Street reading that without balking at the no-deal scenario.

But even if he considered such difficulties exaggerated or unlikely, he has to recognise what the last six weeks have vividly proved – that in a contest between the Government and Parliament, it is Parliament that holds all the trump cards. “Do or die” has always been based on the illusion that ministers hold the decisive power – in fact it is not currently within their gift to do or even to die. Before anyone becomes outraged at Boris for giving more ground or settling on terms well away from his original plans, they should understand what Parliament would be capable of doing in the event of him not arriving at a deal.

Heads of government in conflict with a determined majority of the Commons are normally doomed to defeat, as Charles I illustrated by losing his head on the block. Parliament can innovate and make up new rules however it wishes, all the more so when not constrained by an impartial Speaker or the threat of an election being forced upon it. Both of those factors are highly unfair to today’s Government and need changing, but neither can be changed this week.

Whenever the Boris ministry looks like it might get away with a no-deal exit, the Commons can do something to block it. The fiasco of the aborted prorogation, which resulted in the passing of the Benn Act in short order, demonstrated precisely that. If, this Saturday, he reports that no agreement has been struck and we are leaving anyway at the end of the month – still the official position of the Government – Parliament has four escalating steps it can take to stop him.

First, if there is any doubt over his obligation to send the humiliating letter set out in the Act, asking for an extension until January 31, the Commons will attempt to enforce it. They can pass any motion they wish to make clear their will, forbid civil servants to cooperate with obstruction of the Act, threaten impeachment, or begin amending it so that someone else writes the letter. They can also sit continuously, 24 hours a day, passing one such motion after another, until he sends it. In the meantime, the Supreme Court would be very likely to rule that the law is clear and the letter must be sent.

An extension until next year and an election before then would quite possibly be the outcome of this, but that could result in Brexit never happening at all. If, alternatively, Boris turned out to be on the brink of outmanoeuvring them all, Parliament has far more weapons at its disposal.

The second available step of escalation is to pass another Act, nullifying any steps to get round the first one. If the Government proposed to become obstructive within the EU, Parliament can pass various laws to forbid that. It can provide for budgets to be paid, force the vacant British seat on the European Commission to be filled, or place a legal duty of cooperation on ministers.

If all that fails, MPS can pass a motion of no confidence in the Government and attempt to install a different administration. So far they have been unable to agree on a potential prime minister, but the imminent implementation of no deal would be quite likely to push them into an agreement.

Their fourth recourse, if Boris remains in office but with a delay to Brexit, is to require further extensions and a new referendum before holding any general election. If just one third of MPS refuse to support an election it will be very difficult to bring one about, and as the Corbyn leadership decays Labour MPS are even less keen on facing the voters. The Tories could end up with Brexit indefinitely postponed, another referendum to fight, economic uncertainty intensifying, and getting blamed for the lot.

The only way of avoiding these dreadful possibilities is to do a deal that can either get straight through Parliament or win such relief and support in the country that the case for a new public vote falls away. Boris Johnson can evidently see that. In contrast to some earlier rhetoric, his strenuous efforts to secure a deal are the right thing to do. Those worried that he is giving away too much should cut him some slack, and understand the formidable power of the sovereign Parliament that it was always their wish to defend.