The court’s 5-2 ruling was released the day before Michigan’s ballot was to be finalized Friday.
The measure will appear on the ballot as Proposition 3, which would establish “an individual right to reproductive freedom, including the right to make and carry out all decisions about pregnancy.”
Supporters of the amendment say it would block Michigan’s 1931 abortion law, which bans all abortions except to save the mother’s life.
“Now more than ever we are excited and motivated to restore the protections lost under Roe,” Darcy McConnell, communications director for the ALL campaign, said in a statement Thursday after the ruling.
“This confirms that more than 730,000 voters read, signed and understood the petitions,” McConnell added, adding that “the opposition’s claims are designed to distract from our efforts to preserve abortion rights under Roe for nearly 50 years.”
In its staff report to the committee, the Bureau of Elections estimated the petition had 596,379 valid signatures — about 146,000 more than the minimum required for certification.
However, opponents have challenged the proposed amendment as there is no space between words in the petition.
In its Thursday order, the state Supreme Court pointed to a 2012 ruling that said only the board’s duty regarding petitions is to determine the form and content and whether there are sufficient signatures.
Michigan law requires that pleadings contain the full text of the amendment after the summary and must be printed in 8-point type.
“Irrespective of the presence or extent of spacing, it is not in dispute that all the words are in the same line and are printed in 8-point type,” the court said.
“In this case, the lack of space between the words did not change the meaning of the words,” the court wrote. “Assuming that the challengers’ objection to the gap is a challenge to the ‘form’ of the petition properly considered by the Board, the petition has met all statutory form requirements, and the Board has a clear statutory duty to certify the petition.”
In a concurring opinion, Chief Justice Bridget McCormack criticized the panel’s two Republican members who voted against certification, saying they would “deny millions of Michiganders their rights.”
“What a sad time,” he wrote.
Judge David Viviano dissented, writing that he could not have found that the petition complied with Michigan law and that the board acted “properly” in reducing certification.
“Failure to include spaces renders the amendment difficult to read and understand. Thus, as the majority points out here, it may have the correct words in the correct order—but the absence of critical word spaces renders the rest of the text very difficult to read and understand, hence the ‘full text’ required by the Constitution and statutes. “Less than,” he argued.
Justice Brian Zahra also dissented, saying he wished the court had heard oral arguments on the issue. He called on the Legislature to amend Michigan’s election law to require the board to certify the ballot at least six weeks before the vote is finalized.
Michigan Republicans blasted the decision along with another on a voting rights referendum initiative. “Despite the court ruling, these measures are very serious for Michigan, and we are confident they will be defeated at the ballot box in November,” Elizabeth Giannone, the state party’s deputy communications director, said in a statement Thursday evening.
Earlier Thursday, Michigan Secretary of State Jocelyn Benson, a Democrat, said the ruling underscored “that the role of the Board of State Canvassers under the law is to ensure the will of the voters.”
The board is scheduled to meet in person at 10 a.m. Friday, according to a news release from the Michigan Secretary of State’s office.
This story has been updated with additional details.
CNN’s Omar Jimenez and Ethan Cohen contributed to this report.