Georgia's system of paying justices of the peace $5 for every search warrant they issue but nothing for warrant requests they reject was struck down as unconstitutional yesterday by a unanimous Supreme Court.

The court ruled that when a magistrate's income depends on the number of warrants he issues, his decisions lack the detachment required by the Fourth Amendment's ban on unreasonable searches and seizures.

The fee system was upheld last July by the Georgia Supreme Court over the dissents of two justices appointed by President-elect Jimmy Carter when he was governor, William B. Gunther and Harold N. Hill Jr. They were outvoted by two other Cater appointees and two justices appointed by former Gov. Carl Sanders.

According to the state court majority, the magistrates, who are unsalaried and often untrained in the law, were competent to decide whether to grant police warrant requests.

"We are not persuaded that a justice of the peace would violate his oath to earn a $5 fee," they said, noting that Winston Murphy, the magistrate in the contested case, had "testified that he had refused to issue search warrants on some occasions."

In his dissent, Justice Gunther said, "I simply cannot hold that neutrality and detachment exist in such a situation . . . It just seems to me that the state has 'stacked the deck' in its favor."

The U.S. Supreme Court agreed with Gunter. The fee system, the court said in an unsigned opinion, provides a judicial officer who "has a direct, personal, substantial pecuniary interest" in his decision to grant or deny permission to conduct a search.