In a span of less than 72 hours, a massacre at a Monterey Park dance studio and a killing spree at two farms in Half Moon Bay left California in anguish. One man carried out his attack with a gun banned by the state, while the other used a gun he legally owned, police said.
The twin shootings, which left 18 people dead, once again drew attention to the patchwork of laws, court rulings and workarounds that have made the United States the gun capital of the world. Even in California, a state with some of the country's strictest gun laws, the limits can be sidestepped.
"It does illustrate the challenges of regulating state by state when firearms are so easily carried across state lines," said J. Adam Skaggs, chief counsel at the gun safety group Giffords Law Center.
The prospects for new federal gun laws are dim. Congress last year passed the first federal gun legislation in decades, including billions of dollars to address mental illness and encourage states to enact laws allowing authorities to confiscate weapons from dangerous individuals, but the newly Republican-controlled House of Representatives is unlikely to advance further gun bills.
Efforts to institute more sweeping limits such as universal background checks and banning high-capacity magazines have repeatedly failed to overcome opposition from Republicans, who say such measures will not deter criminals while infringing upon the rights of law-abiding gun owners.
Any new federal law would also have to survive legal challenges at the U.S. Supreme Court, whose conservative majority expanded gun rights in a landmark ruling last June that established carrying a weapon in public as a basic right.
Gun control groups such as Giffords and Everytown for Gun Safety say they are taking the long view while also pursuing non-legislative avenues, including increasing public pressure on the gun industry to prioritize safety.
Everytown has partnered with mayors in 31 cities to release data tracking the manufacturers of guns recovered in crimes, part of a campaign to convince the public that gun companies are profiting off violence. The goal is to force gun makers to implement new measures, such as cutting ties with dealers that sell at gun shows where background checks are not required, according to the group.
Everytown's legal arm, meanwhile, has filed lawsuits against gun manufacturers on behalf of mass shooting victims.
"A missing piece of the gun debate in this country is the industry," said Nick Suplina, senior vice president for law and policy at Everytown.
Other countries, such as the United Kingdom, New Zealand and Australia, have curtailed mass shootings by banning handguns or semiautomatic long guns and buying back millions of weapons, taking them out of circulation.
Those options appear remote in the only country with more privately held guns than people, gun-control advocates say. So long as guns are available in some parts of the United States, individuals determined to carry out mass attacks can likely obtain the weapons they desire, Skaggs said.
"If you know you can't pass a background check in Michigan, you can just drive to Ohio and buy from a private seller," said April Zeoli, a professor at the University of Michigan's Institute for Firearm Injury Prevention. Federal background checks only apply to licensed dealers, not private transactions.
The majority of guns used in mass shootings were obtained legally, according to the nonprofit Violence Project, which maintains a database of attacks.
The gun Huu Can Tran used during the ballroom shooting on Saturday is banned for sale in California. The county sheriff said he also used a high-capacity magazine, which California defines as one that holds more than 10 rounds and has outlawed. Authorities have not said where Tran acquired the weaponry.
Chunli Zhao legally owned the gun used in the Half Moon Bay attack on Monday, police said.
Only eight states have enacted laws banning certain high-capacity semiautomatic weapons of the type often used in mass shootings, according to Giffords Law Center. Six states have passed laws requiring background checks to purchase ammunition in addition to guns; in most other states, ammunition can be bought with no oversight.
Giffords and other advocacy groups say states with tougher regulations tend to have less gun violence, including suicides and homicides. California, for instance, ranked 43rd in the rate of gun deaths in 2020, according to federal data.
The RAND Corporation's Science of Gun Policy initiative released its latest report this month, finding some evidence that banning high-capacity magazines lessens mass shootings but inconclusive evidence regarding the impact of background checks on such incidents.''
Gun control advocates say they know the steep obstacles they face. The National Rifle Association spent decades working towards the 2008 Supreme Court opinion that ruled the U.S. Constitution guarantees Americans an individual right to own guns.
The sort of national cultural shift needed to reverse that may take a similarly long time, Skaggs said.
"Changes in politics and changes in constitutional law and jurisprudence don't happen quickly," he said. "They take years or decades or generations."
* The writers are from the Reuters news agency