Because the deadline has passed to certify initiative titles, the court had allowed the measure on the general election ballot while it decided whether the votes will be counted.
Arkansas voters in 2016 approved a constitutional amendment legalizing medical marijuana. The proposed amendment would allow those 21 and older to possess up to an ounce of cannabis and would allow state-licensed dispensaries to sell recreational marijuana.
The Board of Election Commissioners rejected the measure after commissioners said they didn’t believe the ballot title fully explained to voters the impact of the amendment. Supporters of the measure argued that the board's criticism went beyond what was required for ballot initiatives.
Justices rejected the board's arguments for denying the measure, but the court also struck down the 2019 law that empowered the board to certify ballot measures. Before that law, ballot measures had to be reviewed by the attorney general before petitions could be circulated.
Two conservative justices agreed that the panel didn't have the authority to reject the proposal, but said Arkansas' Republican secretary of state also correctly found the proposal insufficient for the state's ballot.
“The proposed ballot title is nether complete enough to reveal the scope of the proposed amendment nor free of misleading omissions regarding the issues of child protection," Justice Shawn Womack wrote in a separate opinion.
A spokesman said Secretary of State John Thurston, who chairs the board of election commissioners, did not have a comment on the ruling.
Recreational marijuana is already legal in 19 states, and legalization proposals are on the ballot this fall in South Dakota, North Dakota, Missouri and Maryland. The Oklahoma Supreme Court on Wednesday ruled a proposal in that state will not appear on the ballot in November.
Responsible Growth Arkansas has raised more than $4 million in support of the Arkansas measure, primarily from medical marijuana businesses. Safe and Secure Communities, a group formed to oppose the measure, has raised more than $2 million from an Arkansas poultry executive and an Illinois shipping executive who have backed Republican candidates.
The Family Council, another group campaigning against the measure, on Thursday called the legalization proposal a “recipe for disaster."
Arkansas Republican Gov. Asa Hutchinson, a former head of the federal Drug Enforcement Administration who has opposed the proposal, did not have an immediate comment on the ruling.