How British Parliament Works

To Americans, this scene might be puzzling. Why would the prime minister, whom Americans think of as the equivalent of the U.S. president, appear in the floor of the House of Commons and argue face-to-face with the opposition party's leader?

The reason is that while the U.K. also has a representative democracy, its parliamentary system is very different from the U.S. Congress. Unlike the U.S, there's no separate executive branch headed by an elected president and a legislative branch with two equal houses.

Instead, in the U.K., those functions essentially are blended, and most of the power is vested in a single legislative body, the House of Commons. The politics that controls the House of Commons faction — currently the Conservative Party — gets to select one of its legislators as the nation's prime minister, the equivalent of the U.S. president, and picks the cabinet members who run the various parts of the government as well.

"Joe Biden was a member of the U.S. Congress as a senator, but had to give up his seat when he became vice president," explains Dr. Matthew Williams, a scholar and expert on British politics who currently serves as the access and career development fellow at Jesus College Oxford. "Boris Johnson is still a member of Parliament for Uxbridge, in West London, and absolutely does not have to give up his seat."

The odd feature of British democracy, and other parliamentary systems as well, is that most voters don't get a chance to choose their national leader, unless they happen to live in the legislative district — called a "constituency" — that the legislator selected by the party as prime minister represents. "And they're not voting for the executive, right?" notes Mariely López-Santana, an associate professor and director of the political science graduate program at George Mason University's Schar School of Policy and Government. "They're voting for a member of the legislature."

In practice, though, since voters generally know who the party plans to pick as prime minister if it wins enough seats, they know that a local vote cast for, say a Conservative, is a vote cast for Johnson.

The U.K.'s Parliament in some ways is far more powerful than Congress. While the U.S. Constitution limits the powers of Congress, the U.K. doesn't have such a written document.

As a result, in theory, "Parliament is sovereign, meaning that Parliament can have no legal limitations placed upon it," Williams says via email. "We don't, for example, have any higher constitutional law that can stop Parliament from enacting any policy it wishes."

"So much of the British system is fuzzy because they have no written constitution," explains Mark Doyle. He's a professor who specializes in the history of modern Britain and Ireland and the British Empire, among other topics, at Middle Tennessee State University, and is the author of several books, including "Fighting like the Devil for the sake of God" a look at religious violence in Victorian Belfast. "And so the rules are kind of this conglomeration of precedent and convention. Sometimes the courts step in from time to time to make rulings. The rules are less clear cut."

Parliament took centuries to evolve into its modern form, beginning with the medieval councils that British kings held with barons to raise money for wars, to the January Parliament summoned under Simon de Montfort, Earl of Leicester, in 1265, which was the first to include representatives elected by their local communities.

By the late 1600s and early 1700s, as the power of the British monarchs slipped, Parliament become more and more powerful. Sir Robert Walpole, who served in the House of Commons from 1721 to 1742, is today viewed as the first prime minister, even though he didn't officially hold the position.

The U.K. once had something closer to a true bicameral system, in which the voting public elected a House of Commons that shared power with hereditary aristocrats and clerical leaders in Parliament's second chamber, the House of Lords.

But in 1911, the Parliament Act took away the Lords' ability to reject funding bills or veto other legislation passed by the House of Commons, and the House of Lords gradually has lost most of its clout.

Today, the House of Lords is largely an advisory body, whose approximately 800 members mostly are experts in education, law, health, the sciences and other fields appointed as life peers by Queen Elizabeth, on advice of the prime minister. Though the House of Lords Act of 1999 took away the seats and voting privileges of most of the aristocrats who inherited their titles and automatic rights to sit and vote in Parliament, there are 92 hereditary peers who still remain in the House of Lords, as well as 26 Lords Spiritual, who are bishops in the Church of England.

Unlike the U.S., where the Democrats and Republicans hold all but two seats in the Senate and one House seat, the House of Commons' 650 members belong to 11 different political parties. The Conservative Party (359 members as of January 2022) is the dominant force, and Labour (199 members) is the main opposition party.

But groups such as the Scottish National Party (45 members), the Liberal Democrats (13 members) and Northern Ireland's Democratic Unionist Party (eight members) also hold seats. Another seven belong to Sinn Féin, a party that wants to pull Northern Ireland out of the U.K. and unify it with the Republic of Ireland. Its members win local elections and then refuse to take their seats in protest, Doyle explains.

In the event that one of the big parties doesn't win enough seats to control the House of Commons outright — a situation called a hung Parliament — it's possible for them to cut deals and form a coalition with the smaller parties to take over the government.

"When you have more political parties, it becomes less likely that one political party will reach 50 percent," López-Santana says.

In the U.K., coalitions have been formed a few times in the last decade. In 2010, the Conservative and Liberal Democrat parties joined forces in an unusual right-left partnership, and in 2017, Conservative prime minister Theresa May clung to power until 2019 by forming a coalition with the Democratic Unionists.

In an era where deep political divisions that make it difficult to accomplish anything in the U.S. Congress, the U.K. system, which concentrates power in the party that controls the House of Commons, might seem like a more efficient way to govern.

"Whichever party controls the House of Commons controls the government," Doyle explains. Right now, the Conservative Party controls 360 seats in the House of Commons, more than the rest of the parties combined. As a result, the Conservatives control everything. "There's no real chance for the gridlock that [the U.S.] has in your system," Doyle says.

But as Williams points out, the U.S. system wasn't created with efficiency in mind. "It was designed to ensure that a wide diversity of voices could be brought to bear on public policy," he says. "Clearly the danger of the British system is that it can easily be steered by whichever party happens to win a majority of seats in the House of Commons."

Another big difference between the U.K. and the U.S. is that control of the House of Commons doesn't change hands that frequently. The last Labour government, as Doyle notes, lost power in 2005, and Conservatives have formed most of the governments over the past century. "In that way, it's slightly more stable," he says. "You don't get the same kind of whiplash that you would get, you know, going from Barack Obama to Donald Trump."

Compared to the U.S. Congress, the U.K. system doesn't have as much room for individual legislators to disagree with the leadership, either.

"In the U.S., individual members of the House and Senate can be quite powerful and have little incentive to listen to what the executive has to say," according to Williams. "In the U.K., the executive and the legislature are fused. This means that an ambitious member of the House of Commons needs to follow the party line or else they will never be promoted. Whilst there are some reasonably high-powered jobs within the House of Commons that are separate from the government, the most powerful roles in British public life are controlled by party whips. The discipline within parties is therefore higher in the U.K."

The U.K. Parliament and the U.S. Congress also are elected differently. Unlike the U.S. system, in which elections are held for members of the U.S. House every two years and Senators are elected to six-year terms on a staggered basis, since 2011, the Fixed-Term Parliaments Act (FTPA) has dictated that elections should be held at five-year intervals. But the law also allows a two-thirds majority of the House of Commons to approve an early election.

The House of Commons also can pass a vote of no confidence in the government, and unless a new coalition is put together in 48 hours, an early election must be called. Legislation has been introduced in the House of Commons to repeal the FTPA, but it hasn't yet been passed.