Handout / Reuters

Boris Johnson has been defeated in Parliament, the first loss of his brief premiership—on his first vote. His government has no majority, members of Parliament are trying to legally stop the government from carrying out its stated agenda, and Johnson is shutting down the legislature for five weeks at the very moment of Britain’s gravest postwar political crisis. All the while, legal challenges are being lodged against the government, and Conservatives are being thrown out of the ruling party en masse or literally crossing the House of Commons floor to defect.

It is political chaos. And yet, this is precisely how it is supposed to work.

Yes, it is messy and uncertain—and baffling to most casual onlookers. But stand back and a different picture emerges, one that makes more sense, in which the constitution and conventions governing Britain’s archaic political system are holding, and pushing the country toward a decision, even if they are being taken to their limits in the heat of the crisis.

The 2016 referendum created a mandate for the United Kingdom to leave the European Union, but not the type of Brexit it would seek. Parliament’s job has been to fill in this gap.

But how should the U.K. decide on which way to proceed? Britain has no codified constitution set down in a single document, as in the United States, creating a supreme set of rules that govern the country. Instead, the U.K. has a mishmash of laws, practices, and conventions that have developed—and continue to develop—organically over time.

If you really wanted to, you could write down all of them, and this document would be Britain’s constitution—on that day. But with the government and opposition using every lever at their disposal, it might be out of date by the time it came off the press.

Of course, the U.K. does have foundational documents that stand the test of time. The 1689 Bill of Rights established the supremacy of Parliament over the Crown after the Glorious Revolution overthrew King James II. (For this and many other reasons, talk of Britain—or, more accurately, England—being somehow more coolheaded, more conservative, than other countries is absurdly ahistoric: England executed its monarch, King Charles I, more than 100 years before the French.)

The fundamental tenet of the British constitution, then, is that Parliament is sovereign—and therefore no Parliament can bind the next. What one Parliament does, another can undo. Parliament, elected by the people, can change its mind, reverse course—or double down. It can kill the King if it wants. True, the current Queen might have recourse to the law if Parliament tried to pull an Oliver Cromwell today. But essentially, this constitutional settlement has not changed: Parliament’s sovereign power remains the core principle governing Britain.

Let’s take one piece of legislation that, on the face of it, appears to change the nature of this constitutional settlement: the 1972 European Communities Act. This made Britain part of the EU, making European law, made in Brussels, supreme over British law, made in Parliament. Yet even this, as we are seeing today, can be repealed. Parliament remains sovereign.

There are other complicating factors: the Human Rights Act, the Good Friday Agreement, and devolution. Britain is also, theoretically, bound by international law, though Parliament could always legislate to become a European North Korea if it wished. It is sovereign.

Much of the rest of the British constitution is legislation, case law, and convention. This means the U.K. has been, traditionally at least, supremely flexible in how it governs itself. In World War II, for instance, both main parties agreed to delay a general election until after the cessation of hostilities. This meant that even though the convention was to hold elections every five years, there was no election for 10 years, from 1935 to 1945. In that time, the premiership changed hands twice: from Stanley Baldwin to Neville Chamberlain in 1937, and from Chamberlain to Winston Churchill in 1940. This was all entirely constitutional.

Ultimately, the core convention is that whoever controls Parliament holds power. This takes us back to Brexit. The problem is, since 2016, no one has really controlled Parliament. In a fractious, historic debate yesterday—largely centered on this very question—the former Conservative Attorney General Dominic Grieve, who has since been kicked out of the party for voting against the government, set out the nub of the issue. “Our constitution is adaptable,” he told MPs. “And I’m afraid it is having to adapt to the reality that our government does not have a majority and has not had one for some time.”

Despite the referendum result, a majority of MPs remain deeply skeptical of leaving the EU and have been willing to vote against any proposal to do so. Today, they will try to make it illegal for Johnson to take Britain out of the EU without a negotiated exit deal.

In 2017, Theresa May sought to wrest control of Parliament in the only way possible: an election. She failed. The country returned a hung Parliament. Britain, it seemed, had not made up its mind.

Unable to build a majority for her Brexit plan, she was eventually forced to resign—following the rejection of her negotiated withdrawal deal in three separate parliamentary votes. It was not a constitutional requirement that she resign, having lost over the central issue of her government, but a convention. Johnson has come in and made his choice: a full-throated Conservative Brexit. But like May, he doesn’t control Parliament and so cannot get his way. The central tenet of the British constitution, unwritten but rooted in the Westminster earth, has held.

Faced with the reality of the situation, Johnson has now asked Parliament to allow an election to take place, seeking a mandate for the plan that he currently cannot enact. This is the essence of British democracy.

His bid, however, was made harder by one of the rare bits of the constitution that is actually codified: the 2011 Fixed-Term Parliaments Act. The act, as the name suggests, sought to fix the length of a Parliament—as in the U.S., where presidents and members of Congress are elected for fixed periods. If a prime minister wished to dissolve Parliament to hold an election, he or she would need a supermajority, or two-thirds of MPs, to do so. (The opposition Labour Party has declared it will not allow an election until it is sure Johnson cannot pursue a no-deal Brexit. It may decide it can never be sure so will block an election in the hope of simply removing Johnson from power and becoming the government itself. If it can assemble a majority, it has the right. Remember, Parliament is sovereign.)

This piece of constitutional tinkering has played a central role in Britain’s parliamentary chaos over the past three years. Previously, prime ministers could make any piece of legislation a confidence measure, by which they meant that the proposal was so important to the government that if it was rejected by the House of Commons, they would either resign to allow a new prime minister to take over—or hold an election to win a majority to enact the law. This had the effect of focusing minds, forcing potential rebels to potentially lose their seats in an election if they decided to vote down the government. The Fixed-Term Parliaments Act changed this calculus overnight. MPs could now vote down the government without it collapsing. Lawmakers had a free shot—and they have taken it over and over again against the government when it has come to Brexit.

The upcoming election—should Johnson be successful in his call for one to be triggered—is the constitutionally correct instrument to solve political impasses. Johnson stands on a platform of Brexit “do or die” by October 31; the opposition Labour Party wants to delay Britain’s exit, negotiate a new deal, and put it back to the people in a second referendum, with the option to scrap Brexit altogether. Almost every other major political party will also seek another referendum. Should either side be able to form a majority after the election, they will have the power to do what they cannot do now.

This, of course, is the optimistic scenario. It would mean the British constitution had done its job: forced the political establishment to form a majority position for a way forward.

There are, however, potential wrinkles, which could test the legitimacy of the constitution. These have not been an issue until now, because convention has meant they were never tested. Yet, Brexit has—to the alarm of many in Westminster—put a question mark next to many of them.

Let’s take a few core examples. First, the prime minister has suspended Parliament for five weeks to limit the maneuvering of his opponents, using his “prerogative power” to do so—powers granted by convention but now being challenged in the courts.

Second, were an election to be called, the prime minister again has the prerogative power to set the date. Though aides have said a poll would likely be held next month, MPs are concerned he could subsequently delay the election beyond October 31, the Brexit deadline. Johnson’s power in this regard is bound only by precedent and convention.

Third, what if Johnson simply refused to do what Parliament instructed of him? At least one minister has left open the possibility that the government would not be bound by a vote of MPs. Would the Queen have to intervene to dismiss the prime minister from office? She has the power, theoretically, as long as there is a majority in Parliament for someone else. These questions have never been an issue—until now.

Finally, and most realistically, what if no party or coalition emerges from the election with a majority? Britain would be back to the drawing board, its constitution working but stretched to its limits by the divisions that have taken hold in Britain—divisions its constitution, ironically, has been so good, for so long, at resolving.

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