LONDON — In the 2016 Brexit referendum and the 2017 general election, Henry Pritchard was not eligible to vote. He was too young.
Now, having surpassed the legal voting age, 18, and eager for the government to change its course on leaving the European Union, he is desperate for an opportunity to have his say.
With Prime Minister Theresa May departing and the Oct. 31 Brexit deadline looming, choosing the country’s next leader is one of the most important decisions in a generation or more to confront Britons. But in the coming week’s election, Mr. Pritchard once again finds himself excluded.
“This is my future, Brexit is my future, but I am not allowed to participate in the process of deciding what that future might look like,” the 19-year-old gap-year student said in a phone interview.
Only 160,000 members of the Conservative Party will vote for Britain’s next leader because under the parliamentary system, the prime minister is elected directly by the governing party. And that is not going down well among the 99 percent of the population who feel shut out of the process. The reality that less than 1 percent of registered voters will make the consequential decision at such a critical time has left many questioning the very foundation of their democracy.
“The future of our country is going to be decided by a handful of out-of-touch toffs,” said Chris Richardson, 21, a civil engineering student.
“The Tories have made a complete mess of Brexit over three years and have ultimately failed,” he added. “It’s not too late to avert the crisis, and the public is desperate to have its say, but instead we are being shut out further and are forced to watch this slow-motion car crash. It’s brutal.”
Until Brexit, few Britons voiced dissatisfaction with their country’s political system. Even when the leader steps down, as Mrs. May announced she would in May after failing to get her Brexit deal through Parliament, there is no requirement for holding a general election. Both John Major and Gordon Brown took office as prime minister without a general election.
Most galling for many is that the decision lies with the Tories, whose party members are determined to have Brexit delivered by Oct. 31 at any cost. That view has been rejected by the majority of the population but trumpeted by Boris Johnson, the front-runner in the prime minister’s race with a 48-point lead, according to a recent YouGov poll.
But despite the dissatisfaction, few people are calling for the prime minister to be elected directly.
“Members of Parliament electing a prime minister is a central part of parliamentary democracy, so even if the system could be changed it would fundamentally undermine the principle of parliamentary confidence,” said Owen Winter, the director of Make Votes Matter, a political group that campaigns for proportional representation.
The current leadership contest, however, has resulted in greater awareness of how unrepresentative the House of Commons is. The share of seats each party gets does not match the share of votes it receives, which has resulted in more people — including Conservative Party members — calling for an overhaul of the “first past the post” voting system. Critics say it favors larger political parties, which have a larger geographical base.
The Conservative Party lost its parliamentary majority in the 2017 general election, but struck a deal with Northern Ireland’s Democratic Unionist Party to support Mrs. May on certain issues in exchange for financial support.
“The new prime minister will have a majority in the House of Commons despite the Conservatives and D.U.P. winning only 43 percent of the vote in 2017,” Mr. Winter said. “If Parliament genuinely represented how people voted, the issue of an internal leadership election would be far less problematic, because the new leader would still have to win the support of M.P.s from multiple parties, representing a majority of voters.”
Having overwhelmingly voted to remain in the European Union, young Britons feel increasingly alienated and ignored by politicians during the Brexit process and the selection of the next prime minister.
“Most politicians don’t campaign directly towards young people simply because of low youth voter turnout, making it not worth their effort, which results in young people’s concerns not being listened to,” said Oscar Redgrave, 17, who started a pro-European Union campaign group for youths in Shropshire, in midwest England.
“It’s really important that young people are listened to,” he added, “because we will have to live with certain policy and other decisions like Brexit for the longest.”
Even pro-Brexit youths are feeling left out.
“Not all Brexit voters believe in leaving no matter what the circumstances,” said Ashley Turner, 24, who works on her father’s farm and supports Mr. Johnson’s rival for prime minister, Jeremy Hunt, who has not committed unequivocally to leaving by Oct. 31. While Ms. Turner favors leaving, she worries that a no-deal Brexit would be a disaster for British agriculture and possibly ruin her family’s business.
“The politicians have a responsibility to avert an economic calamity, and I think Jeremy Hunt is capable of leaving with a good deal,” Ms. Turner said in a phone interview. “But what does our opinion matter when we don’t even get a vote? It’s a weird kind of democracy we live in.”
Even though Mr. Johnson is pledging to meet the Brexit deadline, many people doubt that he can manage it in the face of a recalcitrant Parliament. That could lead to a no-confidence vote and a general election, many analysts say, but it is not clear that the public supports that outcome, either.
“The two most popular options are either leaving without a deal or having another referendum and changing our minds,” Britain’s leading polling expert, John Curtice, a professor of politics at the University of Strathclyde, said in an interview.
Among the public, Mr. Johnson and Mr. Hunt are running neck and neck, according to the Ipsos/MORI, a widely respected pollster.
But Terry Grossman, 43, a member of the opposition Labour Party who lives in London, dismissed the Tory leadership contest as a “waste of time,” saying that it only made the prospect of leaving by the October deadline less realistic.
“The campaigning is a joke,” Mr. Grossman said, scoffing at a West London pub on Friday. “We are in the middle of a national crisis over Brexit and they are putting things like fox hunting back on the agenda to appeal to the few thousand elites who will vote for them.”
Betty Logan, a 34-year-old trainee nurse, also dismissed the leadership campaign as an exercise in futility.
“It took Theresa May three years to try and figure it out, and she failed,” said Ms. Logan, who added that she would consider moving abroad with her family if Britain left the European Union without a deal. “How on earth is a backtracking buffoon like Boris going to deliver this in three months? It’s not going to happen. We need another referendum.”
In the latest “What U.K. Thinks: Poll of Polls,” an average of the six most recent polls on Brexit, Britain remains about as evenly divided now as it was three years ago — a state of affairs that most say is agonizing and destructive.
“I think the worst thing for this country is this deadlock over Brexit, because other important issues are being neglected,” said Melissa Logan, Betty’s Logan’s sister. “I voted to remain, but we can’t keep living in limbo. If it’s going to be a no-deal, then so be it. At least we will be moving forward.”