WASHINGTON (AP) — Supreme Court decisions to allow inmates to be put to death or to grant a rare reprieve often come at the last minute, and sometimes after the appointed hour of execution has come and gone.

That was the case Tuesday night in Georgia, where Marcus Wellons was pronounced dead just before midnight, nearly five hours after he was scheduled to be executed.

But there is less mystery to the high court process than one might think:

THE "DEATH CLERK"

The justices and their clerks know well in advance when executions are scheduled and where. A court official informally known as the death clerk sends around a weekly update and is in frequent contact with lawyers for inmates and the states as the date of execution nears.

As lawyers for condemned inmates press the case for delay in state and lower federal courts, the Supreme Court receives information about developments and, eventually, copies of those decisions.

LATE FILINGS

Very often those lawyers bring those arguments or similar ones the highest court in the country in a final attempt to save their clients' lives. On Tuesday, for instance, lawyers for Wellons and the state of Georgia were filing legal papers at the Supreme Court well into the evening.

The justices' rejection of Wellons' various appeals was issued roughly an hour after the last filing was submitted. And Wellons was executed just over an hour later.

FATEFUL DECISIONS

When an emergency appeal reaches the Supreme Court, it is directed to the justice who oversees the state in which the execution is scheduled. But death penalty appeals almost always are referred to the entire court.

The justices typically do not meet in person to discuss these cases, but confer by phone, and sometimes through their law clerks, according to the court's guide to emergency applications.

It takes five justices, a majority of the court, to issue a stay. The overwhelming bulk of last-minute appeals are denied, and often without comment.

Occasionally, one or more justices will dissent from the decision to let the execution take place. Even more rarely, a justice will explain why.