MONTGOMERY -- Death row inmate William Kuenzel waited too long to file his latest appeal, a state court ruled Monday.

Kuenzel, who was sentenced to death more than 25 years ago for the 1987 murder of Sylacauga convenience store clerk Linda Jean Offord, sought to overturn that conviction on the grounds that a key witness in the case said one thing to a grand jury and another in the trial. The Alabama Court of Criminal Appeals ruled that Kuenzel waited too long to press that claim.

"Only when he did not obtain the relief he wanted in federal court did Kuenzel decide to pursue a state remedy," Judge Elizabeth Kellum wrote in the court's opinion.

Kuenzel, 53, was convicted in 1988 of capital murder. Prosecutors said he killed Offord with a 16-gauge shotgun during a late-night robbery of Joe Bob’s Crystal convenience store. Kuenzel's roommate, Harvey Venn, testified that he waited in a car while Kuenzel went in to rob the store. Venn served 10 years in prison for his role in the robbery.

Kuenzel's lawyers challenged the conviction in state court on the grounds that in Alabama, a person can't be convicted of a capital crime solely on the basis of an accomplice's testimony.

Another witness, April Harris, told jurors in 1988 that she recognized Kuenzel and Venn at the store when riding past in a car about an hour before the killing. In 2010, Kuenzel's lawyers unearthed grand jury testimony that showed Harris saying she "couldn't make out" who was in the store.

The inmate brought an appeal in federal court, and saw it rejected there. The U.S. Supreme Court declined to hear the case. Then he brought it back to the state appeals court. In their ruling, judges noted that appeals based on new evidence have to be brought six months after the evidence is discovered.

David Kochman, Kuenzel's attorney, said he would apply for a re-hearing of the case, and if denied would try to take the matter to the Alabama Supreme Court.

"I think the point is that this decision turns exclusively on procedure without considering the merits," he said. "This is a case where form cannot prevail over substance."

Kuenzel was originally scheduled to die by lethal injection March 19, but his execution was stayed so the appeals court could hear his case.

Drug challenge could continue

Eight others, also scheduled for execution this year, saw their executions stayed when the U.S. Supreme Court took up a challenge to Oklahoma's lethal injection protocol.

Like Alabama, Oklahoma uses midazolam as the first drug in a three-drug combination for lethal injection. The drug is supposed to kill the pain caused by the potassium chloride used to stop an inmate's heart. After a botched execution with the drug in Oklahoma last year, inmates argued that use of the drug was illegal under the constitutional ban on cruel and unusual punishment. Alabama's scheduled executions were put on hold pending a ruling in that case.

Last month, the Supreme Court upheld the use of the drug, saying that inmates hadn't identified another available drug that would cause less pain.

The condemned Alabama inmates and the state attorney general had until Monday to file new motions in response to the Supreme Court ruling. An attorney for five of the inmates —  not including Kuenzel —  said his clients are continuing to challenge Alabama's execution protocol. He said Alabama's execution procedures may not be exactly the same as the procedures used in Oklahoma.

"My clients and I know way more about Oklahoma's protocol than we do about Alabama's," said John Palombi, who works as a federal public defender in Montgomery. "That's the issue here."

Asked for comment on the Supreme Court case, attorney general spokesman Mike Lewis said in an e-mail that the attorney general's office was in the process of filing motions to dismiss complaints by all eight inmates.

Alabama hasn’t executed an inmate in two years, due to legal challenges and shortages of drugs.

Capitol & statewide reporter Tim Lockette: 256-294-4193. On Twitter @TLockette_Star.