LITTLE ROCK, Ark. (AP) — The Arkansas Supreme Court has halted one of two executions planned for Thursday night, once again throwing a wrench in the state's plans to conduct several executions before the end of April, when one of its lethal injection drugs expires.

The court ruled that Stacey Johnson could pursue his requests for enhanced DNA testing in hopes of proving his innocence in the 1993 rape and killing of Carol Heath. The Innocence Project filed the appeal along with Johnson's attorney.

"We've established that modern DNA testing methods can prove Mr. Johnson's innocence, and Arkansas law clearly established that Mr. Johnson is entitled to that testing," said Karen Thompson, a staff attorney with the Innocence Project, on Tuesday after the appeal was filed. "It's just common sense that before the government sends a man to his death, we should use the best scientific methods to make sure we have convicted the right person."

In its 4-3 ruling, the state's highest court followed the same split it did on Monday, when it halted two other executions involving different inmates.

"Today, our court gives uncertainty to any case ever truly being final in the Arkansas Supreme Court," Justice Rhonda Wood wrote in a dissenting opinion.

Inmate Ledell Lee is also set for execution Thursday night but he also has legal challenges pending before several courts, including a similar request for more DNA tests.

A spokesman for Arkansas Attorney General Leslie Rutledge said the state is reviewing its options regarding Johnson's case. The state can ask the Arkansas Supreme Court to reconsider its decision or appeal to the U.S. Supreme Court, which on Monday opted not to vacate a separate stay involving inmate Don Davis.

Also still pending is a lawsuit from the medical supplier McKesson Corp., which says it sold the drug vecuronium bromide to the Arkansas Department of Correction for inmate medical care, not executions. The company sued to stop Arkansas from using the drug in the planned lethal injections, and a hearing over that issue was underway in Little Rock on Wednesday afternoon.

A state prison official testified that he deliberately ordered the drug last year in a way that there wouldn't be a paper trail, relying on phone calls and text messages. Arkansas Department of Correction Deputy Director Rory Griffin said he didn't keep records of the texts, but McKesson salesman Tim Jenkins did. In text messages from Jenkins' phone, which came up at Wednesday's court hearing, there is no mention that the drug would be used in executions.

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