LITTLE ROCK — The Arkansas Supreme Court on Thursday struck from the ballot one of two measures to legalize medical marijuana in the state, finding that supporters did not comply with a state law governing the use of paid canvassers.

In a 5-2 decision, the state’s top court said no votes cast for Issue 7, which sought to legalize medical marijuana through an initiated act, are to be counted. Issue 6, which would legalize medical marijuana through a constitutional amendment, remains on the ballot.

The Supreme Court issued the ruling in a lawsuit filed by Little Rock lawyer Kara Benca. She argued that of the 77,516 signatures in support of the measure that the secretary of state’s office deemed valid, several thousand should be invalidated, and the measure should be denied ballot access for failing to meet the threshold of 67,887 valid signatures of registered Arkansas voters.

Benca argued that 8,620 of the signatures should be invalidated because the measure’s sponsor, Arkansans for Compassionate Care, did not show that it obtained background checks for some paid canvassers; provided dates for some background checks that conflicted with the dates on the background checks; did not disclose some canvassers to the secretary of state; and disclosed some canvassers after they began collecting signatures.

A special master the court appointed in the case, John Robbins, said in a report last month that most of the canvassers were volunteers, that many who identified themselves as paid were to be paid only if funds contributed to the petition drive in the future allowed, and that many of those canvassers were never paid. He found that Benca did not identify which canvassers were paid and said he could not determine which, if any, of the 8,620 signatures should be invalidated.

In its majority opinion Thursday, the Supreme Court said the special master erred and found that all 8,620 signatures should be invalidated. The court said that once a sponsor identifies a canvasser as paid, it must comply with the relevant requirements, regardless of whether the canvasser ever receives payment.

Benca also argued that 3,329 signatures should be invalidated because some canvassers gave a post office box or a business address instead of a residential address and some signers failed to give an address. The special master said in his report that only some of the signatures should be invalidated, finding that some of the irregularities were merely clerical errors, but the Supreme Court said Thursday that all 3,329 should be invalidated.

Benca further argued that 155 signatures should be invalidated because canvassers verified petitions before voters signed them. The special master found that these were just clerical errors and said the signatures should be counted, but the Supreme Court said Thursday that all 155 should be invalidated.

The Supreme Court said its ruling disallowed 12,104 signatures, leaving 65,412 valid signatures, or fewer than the 67,887 needed to qualify the measure for the ballot.

Chef Justice Howard Brill and Justice Paul Danielson said in dissenting opinions they would have upheld the special master’s findings. Justice Courtney Goodson said in a separate opinion she concurred in the decision to strike Issue 7 from the ballot but said she was writing to comment that the state law on paid canvassers places undue restrictions on the petition process.

“Without question, the act imposes arduous and burdensome requirements to the procedures for circulating and filing petitions for initiatives and referenda. By erecting such obstacles, the act imposes a chilling effect on the rights of our citizens to initiate laws,” Goodson said in her concurring opinion.

Arkansas for Compassionate Care said in a statement Thursday it encourages Arkansans to vote for both Issue 6 and Issue 7.

“ACC placed a medical cannabis law on the ballot in 2012 and we were narrowly defeated,” said Ryan Denham, the group’s deputy director. “We came back with an army of volunteers and successfully placed Issue 7 on the ballot. We’ve been up against many hurdles, including the governor, attorney general, surgeon general, a competing campaign and two lawsuits. We will keep fighting, ensure that no patient faces arrest for using a safe and effective medicine, whether that protection comes from Issue 6 or Issue 7.”

Jerry Cox, executive director of the Family Council Action Committee, said in a statement Thursday the court “did the right thing” by disqualifying Issue 7 but said Issue 6 “is just as bad as Issue 7, if not worse.”

“Issue 6 gives a handful of businesses a powerful monopoly over the marijuana industry,” he said. “It lets people buy, sell, and smoke marijuana as ‘medicine.’ It opens marijuana stores in Arkansas. Candy and soft drinks containing marijuana will be sold as ‘medicine.’ Schools won’t be able to stop students, teachers, bus drivers and others from using marijuana. Employers won’t be able to fire employees who test positive for marijuana.”

Early voting for the Nov. 8 general election began Monday.