WASHINGTON – The Supreme Court vacated a federal appeals court decision Monday for a simple reason: It was filed after the judge who wrote it had died.

"Federal judges are appointed for life, not for eternity," the justices wrote in an unsigned, five-page opinion.

A California county had asked the Supreme Court to reconsider the U.S. Court of Appeals for the 9th Circuit ruling in part because it was written by Judge Stephen Reinhardt, who died March 29, 2018 at age 87. The ruling was filed 11 days later, on April 9.

"Deceased judges cannot decide cases," Shay Dvoretsky, the lawyer for the school district, argued in court papers.

The Supreme Court agreed, noting that Reinhardt's reasoning in the case was endorsed by just six of the 11 judges on the panel, which meant his vote was critical. Although the decision wasn't altered after his death, the high court said judges could have changed their votes, making it an active case until the decision was issued.

"Because Judge Reinhardt was no longer a judge at the time when the en banc decision in this case was filed, the Ninth Circuit erred in counting him as a member of the majority," the justices said. "That practice effectively allowed a deceased judge to exercise the judicial power of the United States after his death."

Reinhardt was a well-known liberal judge who served on the equally liberal appeals court for more than 37 years. He was the last appeals court judge in active service who was appointed by President Jimmy Carter.

The justices' order does not settle the central issue in the case – whether men and women can be paid differently for the same work because of their prior salaries.

Fresno County hired a female math consultant at a lower salary than her male counterparts. School officials reasoned that salary history was a permissible, gender-neutral basis for determining pay rates under the federal Equal Pay Act of 1963.

The appeals court disagreed last year in an opinion written by Reinhardt, ruling unanimously that "prior salary alone or in combination with other factors cannot justify a wage differential" because it would perpetuate a pay gap between men and women.

Thirteen states, including California, and 10 local governments now prohibit employers from seeking job applicants' salary history. But federal appeals courts are split on whether prior pay can be considered along with other factors.

The central issue in the case is whether salary history is a job-related factor, such as work experience, ability and performance. Because women historically have been paid less than men for the same job, the appeals court ruled that it was not.

"If money talks, the message to women costs more than ... billions. Women are told they are not worth as much as men," Reinhardt wrote for six of the court's 11 judges, all of whom agreed with the result. "Allowing prior salary to justify a wage differential perpetuates this message, entrenching in salary systems an obvious means of discrimination."

The appeals court now must consider the case anew, without Reinhardt's presence.