In a surprise announcement, Britain's prime minister called for an early election on June 8. (The Washington Post)

On Tuesday, British Prime Minister Theresa May called for a snap election. If her plan is approved, Britons will go to vote for their new parliament on June 8, bringing forward an election originally scheduled for 2020 by three years.

Since Britain's vote to leave the European Union last June prompted then-Prime Minister David Cameron to step down, there has been some speculation that a new election could be held ahead of schedule. The vote would not only serve as a chance for May's Conservative Party to informally ratify the Brexit vote, but it may also allow them to take seats from the center-left rival Labour Party.

Still, ahead of May's announcement on Tuesday, many British political commentators were doubtful that an early election would be called. Shortly before the news broke, Daniel Finkelstein, a well-respected political columnist with the Times of London, even suggested May was not going to announce a vote.

Finkelstein has since spent the day offering mea culpas, but he wasn't alone in misreading the situation. May's announcement genuinely took many in Britain's political world by surprise, and not without reason: The prime minister and her staff had repeatedly and unequivocally ruled out having an election.

Here are some clear examples:

  • On June 30, 2016, as May launched her bid for leadership of the Conservatives, she said: "‘There should be no general election until 2020.
  • During a BBC interview on September 4, 2016, May said: “I'm not going to be calling a snap election.”
  • On March 7, a source in May's office told the Telegraph that an early election was “not something she plans to do or wishes to do.”
  • On March 20, May's spokesperson told a group of journalists: “There is no change in our position on an early general election. There is not going to be a general election.”

Clearly, May changed her mind. What's not clear is exactly when she did that and why. While announcing her plans for a vote, the prime minister said she had “concluded that the only way to guarantee certainty and stability for the years ahead is to hold this election and seek your support for the decisions I must take,” adding also that she had only taken the decision “recently and reluctantly.”

May will now have to convince some in Parliament that an election is the right move. Under Britain's Fixed-Term Parliaments Act 2011, a period of five years is normally required between elections. This can be bypassed if two-thirds of the House of Commons agree or if there is a motion of no confidence in the government. It is also possible to change the law.

May's flip on calling for an early election stands in contrast to the example of former prime minister Gordon Brown.

Brown, like May, became prime minister after his predecessor, Tony Blair, resigned in 2007. He was elected Labour Party leader, and thus prime minister, in an internal party vote. Despite widespread speculation that he would call an early election to give him the public's mandate, Brown eventually decided not to — a decision many say helped contribute to his and the Labour Party's defeat in the scheduled 2010 election.

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