The plaintiffs sued the city and county of San Francisco in 2009, challenging a 2007 ordinance requiring all handguns to be set on trigger lock.
The plaintiffs claim that requiring handguns to be rendered "inoperable at all times," makes it impossible for its members to use guns for self-defense, "particularly in urgent, life-threatening situations."
The ordinance also prohibits the firing of guns within the home in self-defense as well as the sale of ammunition "specifically designed for use in self-defense emergencies," the complaint states.
"What's the point of having a gun that doesn't work?" asked plaintiffs' attorney Don Kates in 2009. "In my opinion this case is a hands-down winner under state law and the Second Amendment."
The plaintiffs also challenged a 1994 ordinance that prohibits the sale of enhanced ammunition in San Francisco, including fragmenting bullets and other bullets "that serve no 'sporting purpose.'"
The plaintiffs moved for a judgment on the pleadings, which was denied. They then moved for a preliminary injunction, which U.S. District Judge Richard Seeborg denied in an order Monday.
Judge Seeborg noted that the plaintiffs "candidly acknowledge" that they sought an injunction partly as "an attempt to obtain a legal ruling, one way or the other, that would permit appellate review."
The dispute centered around the U.S. Supreme Court ruling, District of Columbia v. Heller, that struck down a similar trigger lock ordinance.
The Supreme Court found that requiring gun owners to use trigger locks "makes it impossible for citizens to use them for the core lawful purpose of self-defense and is hence unconstitutional."
Judge Seeborg found "Heller left too much unsettled for it to dictate a particular result" in this case.
"Against the backdrop of evolving law, and in the absence of controlling precedent, the conclusion emerges that plaintiffs have failed to show a probability of success on the merits of their claims that the challenged ordinances are constitutionally infirm," the judge wrote.
The judge noted that "law in this arena undoubtedly will continue to develop" with more precise analytical standards for Second Amendment challenges.
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