The mass shooting at the Gilroy Garlic Festival in Northern California over the weekend provided a particularly horrific illustration of a common pattern: With California’s many restrictions on firearms, criminals often get their weapons from nearby states with comparatively lax gun laws.

During a Monday news conference, Gilroy Police Chief Scot Smithee said the perpetrator, a 19-year-old local man, used an AK-type rifle purchased in Nevada to carry out a rampage that left 12 people injured and three dead. A federal law enforcement source told the San Francisco Chronicle that the gun was a WASR 10, an AK-47 derivative banned by California’s assault weapons ban.

The shooter purchased the weapon from Big Mikes Gun and Ammo, a six-hour drive from where he lived. Michael Christopherson, the owner of the store, expressed his condolences to the victims of the shooting on the company’s Facebook page. Christopherson wrote that when he sold the weapon to the shooter he had “no reasons for concern” and that the shooter seemed “happy.”

“I would never ever sell any firearm to anyone who acted wrong or looks associated with any bad group like white power,” said Christopherson via Facebook. Big Mikes currently sells WASR 10 rifles for around $700.

California has among the strictest gun laws in the country. The state has universal background checks, waiting periods, and severe limits on the design and functionality of the semiautomatic rifles it allows residents to own. Late last year, lawmakers raised the minimum age for purchasing a rifle to 21.

But nearby states like Nevada and Arizona have no such laws. As a result, these border states have become hotspots for gun traffickers and criminals eager to bring weapons into California.

According to the most recent federal data available, the Bureau of Alcohol, Tobacco, Firearms, and Explosives traced 1,554 firearms from California crime scenes back to Nevada in 2017. Only Arizona, which accounted for 2,185 crime guns that year, supplies more of California’s crime guns.

Nevada Is a Leading Source of California Crime Guns

Washington

392

Oregon

449

Nevada

1,554 guns

California

Arizona

2,185

Texas

764

Washington

392

Oregon

449

Nevada

1,554 guns

California

Arizona

2,185

Texas

764

Washington

392

Oregon

449

Nevada

1,554 guns

California

Arizona

2,185

Texas

764

Source: 2017 ATF Firearms Trace Data. Graphic: Daniel Nass.

An analysis by FiveThirtyEight showed that across the country, firearms tend to move from states with loose gun laws to neighboring ones with tighter controls. California was found to have the third-strictest gun laws in the country, behind only Hawaii and Massachusetts.

The Gilroy shooting isn’t the first high-profile criminal act in which weapons used in California were originally obtained from Nevada. In 2013, a former Los Angeles Police Department officer declared war on the police. In a manifesto, he bragged about circumnavigating the federal background check system by purchasing a short-barreled rifle and suppressor in Nevada. He’d later kill four people, resulting a 10-day manhunt. In 2018, three Nevada residents were sentenced in federal court for orchestrating an arms trafficking scheme that moved dozens of weapons from Reno into the Bay Area. The weapons, which were legally purchased in Nevada, drew the attention of federal authorities when the guns started appearing in robberies and murders.

Research has also documented how the looser standards of its neighbors undermine California’s stringent gun laws. In 2017, researchers at the University of California, Berkeley, released a study probing the potential link between gun shows in Nevada, where private vendors can sell to people banned from guns without putting them through a background checks, and firearm-related deaths and injuries across the border in California. The study found that in the two weeks following a Nevada gun show, hospitals in California within two hours of the border see a 70 percent increase in gun-related deaths and injuries.