NBC 7 has been investigating how U.S. Marine veteran Edwardo Arriola, who has been charged in the shooting death of Navy Corpsman Devon Rideout, was able to buy a gun after he was discharged from the Corps following schizophrenia diagnosis.
Having a diagnosis of a mental illness does not disqualify a person from buying or possessing a firearm. Arriola shouldn't have been able to buy a gun because a military judge ruled him as a quote "mental defective" during a military court hearing.
Under federal law it is illegal for any person to sell or otherwise dispose of any firearm or ammunition to any person knowing, or having reasonable cause to believe that such person, “has been adjudicated as a mental defective or has been committed to any mental institution.”
The legal definition, "If you have been determined by a court or commission that you are as a result of mental illness a danger to yourself or others or found incompetent to stand trial by reason of lack mental responsibly."
The military court ruling came after Arriola, a helicopter technician who joined the Marines in 2011, went to Mexico and did not return in 2014.
It was two years later, according to a Marine Corps official, that Arriola was arrested by Border Patrol Agents and returned to the Marine Corps where he was held in the brig prior to a hearing to determine if he should stand trial for unauthorized absence.
A Marine Corps spokesman told NBC 7 a judge found Arriola incompetent to stand trial.
Gun control advocates say that is when Arriola’s information should have been given to the agency responsible for entering his name into the National Instant Criminal Background Check System.
“If an active-duty servicemember is found incompetent to stand trial in a military court, military authorities would then be required by federal law to properly report that record to the FBI’s gun background check system to ensure that the person could not pass a background check to acquire a deadly weapon,” said Ari Frelich with the Giffords Law Center to Prevent Gun Violence.
The Marine Corps spokesman said the Corps did not believe that submitting a name was required back in 2016, so Arriola’s name was not entered in the system.
According to the Marines, at the time Arriola attempted to buy the gun they were contacted by the California Department of Justice and provided detail to them about his background.
NBC 7 reached out to the California Department of Justice for comment and hasn't heard back from the state agency.
The San Diego District Attorney’s office said in court that Arriola legally purchased the gun used in the alleged murder.
Prosecutors say Arriola “ambushed” Rideout in broad daylight as she exited her Oceanside apartment to take her dog for a walk on Friday, July 20. They say she had just gotten home and was still wearing her Navy uniform when she was killed.
Police officers were called to the complex on Los Arbolitos Boulevard just before 4 p.m. and arrived to find Rideout in the breezeway outside her unit. She was suffering from gunshot wounds, police said.
First responders tried to revive her but she was pronounced dead at the scene. Prosecutors said Arriola tried to prevent witnesses from getting to Rideout to help give her emergency aid.
Arriola, who lived in the unit above Rideout, was arrested the next day on suspicion of murder.