SAN FRANCISCO — In an unusual outcome, the California Supreme Court split Monday over whether to uphold the death sentence of a man convicted of killing a jewelry store owner during a 1996 robbery in Fresno.

The court generally reaches unanimous decisions in death penalty cases.

With Associate Justices Mariano-Florentino Cuellar and Goodwin Liu dissenting, the court ruled that defendant Vaene Sivongxxay chose not to have a jury decide his case at the outset of his trial and had no right to be advised specifically that a judge would also decide the allegation that he committed murder during the course of a robbery.

That allegation made Sivongxxay eligible for the death penalty.

The trial court did not ask Sivongxxay separately whether he waived his right to a jury trial on the robbery and murder allegation. But the five justices in the majority said the error did not taint the trial since there was no evidence Sivongxxay would have chosen to have a jury decide the allegation.

The ruling upheld Sivongxxay’s death sentence.

Kirk Jenkins, an appellate lawyer who studies the California Supreme Court, said it reached unanimous decisions on death penalty cases more than 75 percent of the time in 2015 and an even higher percentage last year.

Still, Jenkins said there was evidence that the court was scrutinizing death penalty cases more closely in the past few years.

Cuellar and Liu said the trial court failed to explain to Sivongxxay that he was entitled to have a jury decide the allegation that he committed murder in the course of a robbery.

Cuellar and Liu also said the trial court failed to ask Sivongxxay separately whether he waived his right to a jury trial on the allegation.

Liu said the majority opinion “undermines an important safeguard of California’s death penalty scheme.”

Cuellar and Liu are relative newcomers to the court. Gov. Jerry Brown nominated Liu to the court in 2011. Cuellar joined in 2015.