A parole panel in Georgia refused on Monday to grant clemency to a man who is scheduled to die by lethal injection on Tuesday evening, apparently unpersuaded by evidence that he was ineptly represented at trial by a drunken lawyer, had an exceptionally harsh childhood and has a severe intellectual deficit.

But in what could be a legal decision with wider effects, lawyers for the man, Robert Wayne Holsey, were still waiting for the Georgia Supreme Court to respond to a last-minute appeal. They argued that the state’s standard for determining intellectual disability in capital cases — the country’s most stringent — runs afoul of a recent decision by the United States Supreme Court.

Mr. Holsey was convicted of armed robbery and murder in 1997 and sentenced to death. He had robbed a convenience store and shot and killed a pursuing officer.

His trial lawyer later admitted that at the time he was drinking up to a quart of vodka daily and facing theft charges that would land him in prison. He said he should not have been representing a client.

On appeal, a Superior Court judge ruled that during the penalty phase of Mr. Holsey’s trial, his lawyer had failed to effectively present evidence that might have forestalled a death penalty, including facts about Mr. Holsey’s history and his intellectual deficit. That judge called for a new sentencing trial.

But the Georgia Supreme Court reversed the decision, ruling that the jury had heard enough evidence about mitigating factors during the initial trial…

The state requires defendants to prove that they are intellectually disabled “beyond a reasonable doubt…”

In other states, either a “preponderance of evidence” or “clear and convincing evidence” is necessary to establish disability, said Eric M. Freedman, a law professor and death penalty expert at Hofstra University. Both are less stringent standards than the one used in Georgia.

Robert Wayne Holsey Faces Lethal Injection in Georgia, NYTimes.com, 12/8/2015