SAN DIEGO -- A year and a half after the death of a San Diego police officer in a shootout, authorities have made another arrest.
Fernando Gallo, a 38-year-old convicted felon with a past drug conviction in San Diego, was arrested in Murrieta Tuesday for possessing firearms, including the gun used to kill SDPD Officer Christopher Wilson.
On October 28, 2010, a probation check at a Skyline-area apartment led to a deadly shootout. Wilson, the shooter Holim Lee and Lee's girlfriend, Lucky Xayasene, all died in the incident.
After nine months, three others in the apartment who did not pull the trigger were charged with murder due to their involvement, which included actions such as switching off the lights prior to the shootout.
At the same time, San Diego police asked federal agents to trace the history of the weapon used to kill Wilson -- a Springfield XD-40, a .40-caliber pistol.
Experts say the most critical thing needed in tracing a gun's history is the serial number. On the Springfield XD-40, the serial number is located on the barrel and on the frame.
Mike Bullock, who manages American Shooting Center in Kearny Mesa, told 10News he has worked on other weapons traces with the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF).
"There's always a chain of custody on a firearm. The ATF tracks it from the manufacturer, to the distributor, and to the retailer, " said Bullock.
According to a federal complaint, the gun's first buyer was a Las Vegas gun dealer who sold it to a man named Gary Saks. Saks then sold the firearm to Gallo, who sold the gun to a friend two months later.
Investigators zeroed in on Gallo, who was not allowed to own weapons due to his status as a convicted felon.
Wilson's ex-wife, Tracy Wilson, said the gun's history isn't a surprise.
"Any dirtbag will get their hands on [a] gun. I'm not going to fault someone about whether people could have been caught at so many steps on the way," she told 10News.
Still, she is comforted by the fact the case is being investigated so thoroughly.
"It's nice to think that after a year and a half after Chris was murdered, San Diego police and other law enforcement remain on top of things, making sure justice is served," Wilson said.
As far as the gun sale, it appears the sale of the handgun to Gallo occurred in Nevada and was legal. Unlike California, Nevada does not require background checks.
It remains unclear how the gun ended up at the Skyline apartment.
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