At the center of the case is Bennie Dean Herring, no stranger to law enforcement, who drove a pickup truck to the Coffee County sheriff’s department one afternoon to check on another of his trucks, which was sitting forlornly in the department’s impound lot for reasons unclear.

As he was preparing to leave, he was spotted by a county investigator, Mark Anderson, who knew him and wondered if there was an outstanding warrant for Mr. Herring’s arrest. No, the warrant clerk said; there are no active warrants against Mr. Herring in Coffee County.

Whereupon the investigator asked the warrant clerk to call the sheriff’s department in neighboring Dale County. Sure enough, the Dale County warrant clerk said: There was an outstanding warrant against Mr. Herring for failing to appear in court on a felony charge.

Acting quickly on that information, Mr. Anderson and a Coffee County deputy followed Mr. Herring, pulled him over and arrested him. A search turned up some methamphetamine in Mr. Herring’s pocket and a pistol under the front seat of his truck.

All this took place within 10 or 15 minutes. Meanwhile, the Dale County clerk had discovered that the warrant against Mr. Herring was no longer active after all. But by the time that information reached Mr. Anderson and the deputy, they already had Mr. Herring in handcuffs.

The defendant moved unsuccessfully to suppress the evidence against him, arguing that it had been seized in the course of an unlawful arrest. A federal magistrate held that the officers had acted in a “good faith belief” that the warrant was active, and had found the drugs and pistol before learning that the warrant had been rescinded.

A federal district judge agreed, and refused to suppress the evidence. A jury convicted Mr. Herring of possessing illegal drugs and being a felon in possession of a firearm, and he was sentenced to 27 months in prison. He has been appealing his conviction on one ground: that the lower court erred in denying his suppression motion.

The United States Court of Appeals for the 11th Circuit ruled on July 17, 2007, that the lower court was right in finding the evidence admissible, and that the circumstances of the Herring case called for an exception to the decades-old exclusionary rule, which attempts to deter police misconduct by barring the use of illegally obtained evidence. The 11th Circuit ruled essentially that the Coffee County officers had acted in good faith, and that it made no sense to punish them for an error committed in a neighboring county.

“Hoping to gain a beneficial deterrent effect on Dale County personnel by excluding evidence in a case brought by Coffee County officers would be like telling a student that if he skips school one of his classmates will be punished,” the 11th Circuit wrote.

In recent years, and with a lineup of justices less conservative than today’s, the Supreme Court has defined circumstances that justify exceptions to the exclusionary rule. So, even though the high court is Mr. Herring’s last chance, its decision to take his case does not necessarily augur well for him.

Separately, the court declined on Tuesday to hear appeals of lower-court decisions concerning who has standing to sue the government over its warrantless wiretapping program, and insurers’ rejection of some kinds of claims on homes damaged during Hurricane Katrina and its aftermath.