50 shades of controversy: a history of the EU exit clause
It is a fitting quirk of history that the 264 words shaping Britain's divorce from the EU were brought to life by British representatives over the objections of federalist colleagues who warned of trouble ahead.
The now-infamous Article 50 triggered by Prime Minister Theresa May came about as part of a grand convention, undertaken between 2002 and 2003, to write an overarching constitution for the EU as it prepared to enlarge deep into eastern Europe.
Looking back today, delegates to the convention recall the rancour that surrounded the very idea of an "exit clause", which was unprecedented in EU law.
"Most people thought the notion that you might ever want to leave was an utter insult," said British lawmaker Gisela Stuart, who was part of the convention's 13-strong executive "praesidium".
The Labour MP fought hard for the exit clause at the convention, noting that it was touch and go whether it would be retained when delegates held their final negotiating session in July 2003.
The convention ended, to the sounds of champagne corks popping and Beethoven's "Ode to Joy", with the clause intact.
Stuart did not share in the joy.
She went on to take a starring role in the pro-Brexit campaign that culminated in last year's referendum decision by voters to make Britain the first country to take advantage of Article 50.
Her revulsion at the EU grew out of what she felt was the elitist spirit of the convention, but was fuelled particularly by later events.
The EU's enlargement did take place, in 2004, but the proposed constitution was then thrown out by French and Dutch voters in referendums.
- A punishment clause -
Despite that stinging electoral rebuff, EU leaders regrouped and bundled much of the legal revamp into a new treaty, signed in Lisbon.
The initial text's "Article 60" lived on in the form of Article 50.
Still, few involved in its evolution thought it would ever be invoked.
Originally, the idea was to encourage adoption of the constitution as quickly as possible by creating a mechanism to kick out a member state if it failed to ratify the text within two years.
"Everyone assumed it would be the British who would have a problem with ratifying the constitution, not the French or the Dutch. So at first it was an expulsion clause," Stuart told AFP in a phone interview.
"But neither at its inception nor in its final stage, when it became the Lisbon treaty's Article 50, did any of its draftsmen consider that it would be needed."
The two-year timeframe for withdrawal lived on in the revamped treaty, but the article's designers did not spell out whether the process can be stopped once it begins.
That ambiguity could become a flashpoint as opponents to Brexit fight a rearguard action to retain Britain's membership, or at least access to the EU's common market.
British diplomat John Kerr, who as secretary-general to the convention was Article 50's draftsman-in-chief, insists that the process is indeed reversible if the member state changes its mind.
- One-way ticket -
In a BBC interview in November, Kerr, a member of the House of Lords, conceded that he had very different circumstances in mind when crafting the article.
"I thought the circumstances in which it would be used, if ever, would be when there was a coup in a member state and the EU suspended that country's membership," he said.
"I thought that at that point the dictator in question might be so cross that he'd say 'right, I'm off' and it would be good to have a procedure under which he could leave."
However, others at the convention predicted that the new clause would be exploited by eurosceptics to make endless mischief.
"At the time the EU's opponents framed the EU as a one-way ticket to an unknown destination in a locked carriage," Dutch representative Gijs de Vries told AFP.
Some of the EU's defenders felt that inserting an exit clause would refute such arguments.
But de Vries said that "the introduction of an exit clause was unlikely to satisfy the populists; on the contrary, I expected it to embolden them.
"I fear the British referendum debate rather proved my point."
AFP / Expatica