U.S. Supreme Court Justice Anthony Kennedy on Wednesday rejected the National Rifle Association’s request for an emergency stay blocking enforcement of Sunnyvale’s new ban on possession of ammunition magazines that hold more than 10 rounds.

The NRA had sought the stay Monday after the 9th Circuit Court of Appeals and a federal trial-court judge in San Jose refused the request last week. Kennedy had ordered Sunnyvale’s lawyers to respond by Wednesday afternoon and then issued his order — brief and without explanation — a short while later.

The NRA represents six Sunnyvale residents who claim the new ordinance, passed by 67 percent of the city’s voters last November as Measure C, infringes upon their constitutional rights.

State law has banned making, selling, giving and lending magazines that can hold more than 10 rounds since 2000. Those who owned them before then were allowed to keep them, but Sunnyvale’s Measure C went a step further by banning possession no matter when they were acquired. The ordinance took effect Dec. 6, giving residents 90 days to either sell their magazines to a federally licensed dealer, store them outside the city, or turn them in to police for destruction.

As of midnight last Thursday, anyone who possessed a magazine that can hold more than 10 rounds was committing a misdemeanor punishable by a fine of up to $1,000, six months in jail or both.

“Sunnyvale voters passed the gun safety ordinance and we’re prepared to defend the ongoing legal challenges against it,” Sunnyvale spokeswoman Jennifer Garnett said Wednesday. “This was just another step forward in that process.”

Chuck Michel, the NRA’s West Coast counsel representing the Sunnyvale plaintiffs, issued a statement Wednesday saying he’s “disappointed but not surprised” that Kennedy refused the plaintiffs the “very rarely granted extraordinary relief we had hoped for.”

“As the courts themselves make clear, this type of denial is not a reflection on the merits of our underlying appeal, which is still going forward in the Ninth Circuit,” Michel said. “Our brief is due in early April, and law enforcement and civil rights groups are already lining up to support us in that effort to stop these infringements on Second Amendment rights.”

Josh Richman covers politics. Contact him at 510-208-6428. Follow him at Twitter.com/josh_richman. Read the Political Blotter at IBAbuzz.com/politics.