A federal judge on Tuesday upheld Maryland's new ban on assault rifles and magazines capable of holding more than 10 rounds, handing at least a temporary victory to state officials who say the measures could ward off mass shootings.
A collection of gun owners, stores and industry groups had sued the state, saying the bans violated their Second Amendment right to bear arms.
Judge Catherine C. Blake disagreed, writing flatly: "I find the law constitutional."
Blake's decision adds to a growing list of legal victories for states that have tightened their gun laws in recent years, even after the Supreme Court decided in 2008 that the Second Amendment guarantees an individual right to bear arms.
Gun rights advocates say they are not disheartened, however, and plan to keep fighting.
The Maryland law has strong backing from top state officials, and Attorney General Douglas F. Gansler, whose office handled the case, praised the judge's ruling.
"The banning of assault weapons and large-capacity magazines is a vital tool in the effort to help protect Marylanders from the most destructive weapons available for use by criminals," he said in a statement.
"This ruling reflects our view that the law in no way infringes the Second Amendment rights of Marylanders."
But Patrick Shomo, president of Maryland Shall Issue, a gun group that is a plaintiff in the case, played down the importance of Tuesday's ruling. He said it was a step in a much longer process and that his side would file for review of the case by the 4th Circuit Court of Appeals.
"This decision allows us to push to the next level," he said.
The General Assembly passed Maryland's law in 2013, shortly after Adam Lanza killed 20 children and six adults at Sandy Hook Elementary School in Newtown, Conn.
The legislation led to unprecedented gun sales; permit applications doubled. Gun rights advocates filed their challenge a few days before it went into effect Oct. 1.
The case has moved swiftly through the court, with the two sides conducting several depositions of witnesses, filing briefs and arguing before the judge over just a few months.
At the final hearing last month, the two sides debated before a packed courtroom over whether the law would be effective and how the judge should apply the Second Amendment to the case.
The gun owners argued that the landmark 2008 Supreme Court ruling meant Maryland could not outlaw entire classes of weapons or magazines that are commonly owned for lawful purposes.
The state's lawyers challenged the assertion that the banned rifles are common. In any case, they argued, restricting particularly dangerous weapons is still permissible.
Blake, who was appointed by President Bill Clinton, wrote that she was not convinced that assault rifles such as the AR-15 are used regularly for self-defense. She wrote that they seemed to be "military style weapons designed for offensive use."
Blake did not rule on whether the weapons or magazines are protected by the Second Amendment. But even if they are, she wrote, the bans are a legitimate way for the state to enhance public safety.
The law "seeks to address a serious risk of harm to law enforcement officers and the public from the greater power to injure and kill presented by assault weapons and large capacity magazines," she wrote.
Blake's ruling joins others from Washington, California, Connecticut and New York, where judges have upheld similar bans.
Adam Winkler, a professor of constitutional law at the University of California, Los Angeles, said courts have found that a variety of restrictions on gun ownership pass muster even after the Supreme Court ruling.
"Case after case has upheld bans on assault weapons," Winkler said. "Gun advocates insist such laws violate the Second Amendment, but courts have disagreed."
The state's victory comes on the heels of a ruling from the 4th Circuit last year upholding the state's restrictions on handing out permits to carry a handgun in public, which are among the toughest in the country. The decision in that case guided Blake's analysis.
But Shomo said that gun rights advocates across the country will continue to fight. Several rulings upholding assault rifle bans are on appeal. Shomo said he is optimistic of ultimately winning another case before the Supreme Court to bolster what he sees as an important victory in 2008.
"Gun control today is limited to poking at the edges of the Second Amendment," he said. "Our community is taking the long view."