Last week, the State of California became the sixth state in the country to call for a constitutional amendment overturning the U.S. Supreme Court’s 2010 ruling in Citizens United v. FEC, and restoring democracy to the people.

With the passage of a resolution through its state legislature, California is the latest to join this growing grassroots movement across the nation. Hawaii, New Mexico, Vermont, and Rhode Island have passed similar resolutions through their state legislatures, and a majority of state legislators in Maryland have signed a letter to Congress supporting an amendment. And, just this past Wednesday, the Montana Secretary of State certified for the November ballot a voter initiative calling for a constitutional amendment, the first such statewide ballot measure in the country.

All of this comes on the heels of another controversial Supreme Court decision, in a Montana case, that makes it clearer than ever that we the people must use our amendment power under the Constitution to defend our democracy.

In January 2010, just five Justices of the U.S. Supreme Court decided, in Citizens United, to sweep away a century of precedent barring corporate money in elections. They asserted that independent corporate expenditures would not corrupt the electoral process nor create the appearance of corruption. They made that assertion without any facts to back it up. This is because the petitioners in Citizens United never presented such facts in the first place and did not seek, in their original complaint, to overturn prior Supreme Court rulings prohibiting corporate political expenditures. These five Justices, on their own, transformed the Citizens United case into a vehicle for unleashing unlimited corporate money in our elections.

Two weeks ago, they had a chance to reconsider the decision—and the facts showing that independent corporate expenditures do lead to corruption and the appearance of corruption—by accepting for review the case of American Tradition Partnership v. Bullock: a case that addressed Montana’s century-old law barring corporate money in elections.

In 1912, the voters of Montana passed the Corrupt Practices Act in response to the dominance and control of their elections and government by the “Copper Kings,” the barons of the copper mining industry during the Gilded Age.

On December 30 of last year, the Montana Supreme Court issued a major ruling upholding the law after a corporate entity, American Tradition Partnership, had challenged it, seeking to spend its money in Montana elections. The state supreme court recounted the extensive evidence of corruption that led to its passage and asked: “When in the last 99 years did Montana lose the power or interest sufficient to support the statute, if it ever did?”

The court cited in this history how W.A. Clark, a Copper King, had purchased a U.S. Senate seat by paying members of the Montana state legislature for their votes. (Prior to the enactment of the 17th Amendment to the U.S. Constitution establishing direct elections of U.S. Senators by popular vote, state legislatures had appointed them.)

When the Senate refused to seat Clark because of the 1899 bribery scheme, he engaged in further corruption to obtain a second appointment, serving in the Senate from 1901 to 1907. Clark’s bribery was so notorious that, as the Montana Supreme Court noted, in 1907 Mark Twain wrote that Clark “is said to have bought legislatures and judges as other men buy food and raiment. By his example he has so excused and so sweetened corruption that in Montana it no longer has an offensive smell.”

When American Tradition Partnership appealed, taking the Montana law to the U.S. Supreme Court, rather than reviewing this history and the factual evidence that justified the law, the Court, by a 5-4 vote, took the extraordinary step of issuing a summary reversal of a state supreme court ruling, denying any merits-based review of that decision. In other words, without even hearing the case or reviewing the factual record before them, the nation’s highest court reversed the Montana Supreme Court and struck down the state’s century-old law. This is a radical action by the same five Justices—just as radical as the Citizens United ruling.

It is time to overrule the U.S. Supreme Court—and we the people have the power to do this.

We have used the Constitution’s Article V amendment power many times before. Seven of our 27 amendments have overturned egregious Supreme Court rulings, and since the Citizens United ruling, people across this country have been mobilizing in support of a new amendment to reclaim our democracy.

Hundreds of resolutions similar to the one approved in California last week have already been passed in cities and towns throughout the nation, including the cities of Boston, Los Angeles, New York, and Seattle. Eleven state attorneys general have joined the call. More than 1,000 business leaders are on board. More than a dozen amendment bills related to Citizens United are now pending in the U.S. Congress. The U.S. Senate Judiciary Committee is planning to hold a hearing on amendment proposals on July 24. And, the President of the United States has said an amendment may be necessary.

The Court’s decision in the Montana case will only further fuel this movement, as it is clearer than ever that this Court, under its current makeup, is not likely to revisit Citizens United any time soon. The last two years of experience under the Citizens United ruling have demonstrated that independent expenditures from corporations and mega-wealthy individuals threaten the integrity of our elections, and we can expect to see even more of this in the coming months.

Americans across the political spectrum agree that corporations are not people and that the promise of government of, for, and by the people must be defended. We are at a crossroads. We’re facing one of our gravest tests. But as in such moments of crisis before, we are coming together, and we will use our power under the Constitution to protect our republican democracy.