While many politicians and activists are strongly encouraging voter registration before the midterm elections this November, North Dakota is moving in the opposite direction — the state is excluding a large portion of its population from voting.

The Supreme Court decided last week — less than a month before election day — to allow a voter ID law in the state that would require voters to supply their name, street address and date of birth in order to register to vote. The requirement could prohibit a sizable number of Native Americans from registering to vote — a breach in democracy that should not be allowed.

The government of North Dakota claims the law is necessary to prevent voter fraud by preventing non-North Dakotan residents from setting up P.O. boxes to vote illegally. A judge had originally overturned it in 2016 on the grounds that voter fraud in North Dakota was “virtually non-existent.”

The problematic part of the reintroduced law is the requirement to supply a home address. Many Native American reservations, which are home to around 20,000 of the state’s 46,000 Native Americans, don’t use street addresses — some use P.O. boxes for their mail, which don’t count as street addresses in the eyes of the voter ID law. In the past, including primaries this year, tribal identification was enough to allow people to vote. Now, this will not be the case during the general election in November.

Native American groups are struggling to find a way around the law to allow people to vote. Justice Ruth Bader Ginsburg wrote in a dissent with Justice Elena Kagan that “70,000 North Dakota residents — almost 20% of the turnout in a regular quadrennial election — lack a qualifying ID.”

This is a large number of voters to disenfranchise, including the homeless population — in which Native Americans are overrepresented. The law will allow voters to use pay stubs or utility bills as forms of identification, but Justice Ginsburg points out that “approximately 18,000 North Dakota residents also lack supplemental documentation sufficient to permit them to vote without a qualifying ID.”

The law seems to be a purposeful move on the part of the Republican-led state government to exclude a large, typically democratic-leaning population from voting. In one of the least-densely populated states in the country, mere hundreds of votes can influence the outcome — Democratic Sen. Heidi Heitkamp, who is up for reelection this year, won her last election in North Dakota by just 3,000 votes.

North Dakota isn’t the only state to pass stricter voter ID laws in recent years. Since the Supreme Court struck down the Voting Rights Act’s requirement that states get federal approval to change voting laws in 2013, Alabama has passed many laws to make it more difficult for minority citizens to vote.

Almost immediately after the Supreme Court made its decision, the state government announced that in 2014, the following year, it would require photo ID to register to vote — but more Alabama voters without photo ID are black or Hispanic than white. Moreover, a year after the law went into effect, the state closed 31 driver’s license offices — where people can go to get photo ID — along distinct racial boundaries. Eight of the 10 counties with the highest African American populations lost offices, compared with only three offices lost in the 10 counties with the lowest percentage of African American voters.

It’s unacceptable for states like North Dakota and Alabama to limit the ability of their citizens to register to vote — in fact, they should be making it easier to register. Preventing voters from participating in the democratic process during a key election season is not only unethical, it’s fundamentally un-American.