Voting booths in Sacramento, California on March 5, 2018. (Justin Sullivan/Getty)

Knut Heidar is a professor of political science at the University of Oslo.

OSLO, Norway — The automatic right to vote should be the essence of democracy. But it doesn’t exist in the United States — unless you remember to register.

The problem is that about one in five U.S. citizens are eligible to vote but not registered. This makes turnout at elections in the United States much lower than in western Europe, shutting out significant voices in the democratic process. This democratic deficit deprives the less resourceful part of the population of its most central political right. It affects political campaigns as well as the election results. Candidates formulate policies and compete for office on the basis of policies targeting only registered voters. The unregistered are secondary citizens and excluded from the national “we.”

But there is an easy way to ensure voting rights: automatic voter registration.

In Norway, all citizens registered in the public census are — if qualified — eligible to vote. Prior to an election, they receive a notification card with the election time and date and the location of their local polling station. It is the duty of the state to update the register, which is identical to the public census. No individual action is required. The register is also used for tax lists, public health care systems, passport issuances and many other public services. Turnout for Norwegian parliamentary elections are today between 70 and 80 percent, while U.S. Congressional elections have a turnout between 30 and 50 percent.

Norway has never had a system that requires individuals to register to vote. For a state striving for home rule and independence throughout the 19th century (Norway was a union with Sweden until 1905), a broad franchise was important to mobilize national support and give legitimacy to political institutions. Suffrage rights came comparatively early to excluded groups, like citizens without property and women. All men could vote by 1898, and women won the right to vote in 1913.

Nowhere is voting a universal right — nor should it be. Norwegian voters must be qualified. Minors cannot vote, although some have proposed giving extra votes to parents. Also, Norwegian courts can deprive those convicted of “crimes against the state” of their voting rights — although the vast majority of prisoners have voting rights. A citizen losing his or her political rights is extremely rare. Prisoners are part of the democratic community, and their punishment should reflect their crimes.

Some argue that the task of registering shows a minimum interest in the vote, which improves the quality of the voters. However, this is kin to arguments used to suppress the extension of suffrage to women and those without property. It is doubtful that voter registration actually improves voters’ decisions.

Unregistered citizens may not have had the know-how or resources that make registering easier, such as a computer, printer or easy access to transportation. A single mother juggling multiple jobs, for example, may not know she needs to register or may not know how to access the form or may not find the time, but if she wants to vote, she should be able to; her voice matters. Keeping legitimate voices out of the democratic process reduces the legitimacy of public decisions.

Democracy as a form of government is not a fixed structure: It develops according to history and choice. Some U.S. states have already introduced the automatic registration of voters. Now it’s time that the federal government stepped up and asked: Do we want the United States to be a true democracy based on “one person, one vote”? If America wants its citizens to have full democratic rights, it must enact automatic voter registration.

This was produced by The WorldPost, a partnership of the Berggruen Institute and The Washington Post.