GILROY (KPIX 5) – A major question remains after the Gilroy Garlic Festival shooting over how the suspect was able to get his hands on that gun.

The answer to that questions, of course, depends on where someone is buying.

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“Without a national law that deals with those things you’re always going to have the problem of guns being trafficked from states with weaker gun laws to states with stronger gun laws,” Giffords Law Center Executive Director Robyn Thomas said.

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The AK-47 derivative used in the Gilroy shooting is not legal in California. And at 19, the gunman was short of California’s 21-year-old minimum for buying any gun.

In Nevada, however, neither of those laws apply. That is where the gun was purchased, and there is evidence that out-of-state guns are frequently used in California crimes.

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“After a gun show in Nevada, we see a spike in gun violence in California cities. So we know for sure that the weak laws in Nevada and even weaker laws in Arizona are influencing gun violence here in California,” said Thomas.

She is executive director for the Giffords Law Center to Prevent Gun Violence, and says people often hear the phrase “gun trafficking” and think of something on an industrial scale. Most of it, really is not.

“Buying a trunk full of guns that wouldn’t be able to be purchased in the state where they’re being sold, driving across state lines and then just selling them out of the trunk of a car on a street corner,” said Thomas.

In this case, it only took one person with one rifle. And that is renewing calls for national standards.

“That’s why we talk about universal background checks as a benchmark starting point for comprehensive gun regulation. Because once you have that nationally, it becomes much more difficult to go to other states when you’re someone who shouldn’t have a gun, to just get a gun by invading background checks in a state like California,” Thomas said.

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Following the Las Vegas shooting, Nevada did approved mandated background checks for all private gun sales. That law will go into effect next year.