At the time of the shootings, he worked for The Experts, a subcontractor on an HP Enterprise Services contract to refresh equipment used on the Navy Marine Corps Intranet network.
His life over the past decade has been checkered.
Alexis lived in Seattle in 2004 and 2005, according to public documents. In 2004, Seattle police said, Alexis was arrested for shooting out the tires of another man's vehicle in what he later described to detectives as an anger-fueled "blackout." According to an account on the department's website, two construction workers had parked their Honda Accord in the driveway of their worksite, next to a home where Alexis was staying. The workers reported seeing a man, later identified by police as Alexis, walk out of the home next to their worksite, pull a gun from his waistband and fire three shots into the rear tires of their Honda before he walked slowly back to his home.
When detectives interviewed workers at the construction site, they told police Alexis had stared at construction workers at the job site daily for several weeks prior to the shooting. The owner of the construction business told police he believed Alexis was angry over the parking situation around the site.
Police eventually arrested Alexis, searched his home, found a gun and ammunition in his room, and booked him into the King County Jail for malicious mischief.
According to the police account, Alexis told detectives he perceived he had been "mocked" by construction workers the morning of the incident. Alexis also claimed he had an anger-fueled "blackout," and could not remember firing his gun at the Honda until an hour after the incident.
Alexis also told police he was present during "the tragic events of Sept. 11, 2001" and described "how those events had disturbed him."
Then, on May 5, 2007, he enlisted in the Navy reserves, serving through 2011, according to Navy spokeswoman Lt. Megan Shutka.
Shutka said he received the National Defense Service Medal and the Global War on Terrorism Service Medal during his stint in the reserves. Both are medals issued to large numbers of service members who served abroad and in the United States since the 9/11 attacks. Alexis' last assignment was as aviation electricians mate 3rd class at the Naval Air Station Joint Reserve Base in Fort Worth, Shutka said.
It was while he was still in the reserves that a neighbor in Fort Worth reported she had been nearly struck by a bullet shot from his downstairs apartment.
In September 2010, Fort Worth police questioned Alexis about the neighbor's report; he admitted to firing his weapon but said he was cleaning his gun when it accidentally discharged. He said he didn't call the police because he didn't think the bullet went through to the other apartment. The neighbor told police she was scared of Alexis and felt he fired intentionally because he had complained about her making too much noise.
Alexis was arrested on suspicion of discharging a firearm within city limits but Tarrant County district attorney's spokeswoman Melody McDonald Lanier said the case was not pursued after it was determined the gun discharged accidentally.
After leaving the reserves, Alexis worked as a waiter and delivery driver at the Happy Bowl Thai restaurant in White Settlement, a suburb of Fort Worth, according to Afton Bradley, a former co-worker. The two overlapped for about eight months before Alexis left in May, Bradley said.
Having traveled to Thailand, Alexis learned some Thai and could speak to Thai customers in their native language.
"He was a very nice person," Bradley said in a phone interview. "It kind of blows my mind away. I wouldn't think anything bad at all."
A former acquaintance, Oui Suthametewakul, said Alexis lived with him and his wife from August 2012 to May 2013 in Fort Worth, but that they had to part ways because he wasn't paying his bills. Alexis was a "nice guy," Suthametewakul said, though he sometimes carried a gun and would frequently complain about being the victim of discrimination.
Suthametewakul said Alexis had converted to Buddhism and was prayed at a local Buddhist temple.
Embry-Riddle Aeronautical University, which offers online courses in aviation and aerospace, confirmed that Alexis was enrolled as an online student via its Fort Worth campus, started classes in July 2012 and pursuing a bachelor's of science in aeronautics.
"We are cooperating fully with investigating officials," the university said.
Alexis arrested in Seattle
The man identified as the shooter in the Washington Navy Yard slayings had been arrested in Seattle in 2004 for shooting out the tires of a parked car in what he described as an anger-fueled "black out."
Two construction workers building a new home told police that Aaron Alexis walked out of a home next door on May 6, 2004, pulled a pistol from his waistband and fired three shots into the rear tires of their parked car.
Alexis later told police he thought the victims had "disrespected him" and "mocked him" earlier that morning after he discovered that his own vehicle had been tampered with. Alexis also told detectives he didn't remember firing his weapon until about an hour later, according to the police report.
Seattle police said in a statement Monday that detectives later spoke with Alexis' father, who told police Alexis had anger management problems associated with PTSD, and had participated in rescue attempts on Sept. 11th, 2001.
When police interviewed the construction workers and manager in 2004, they told police Alexis had "stared at the construction workers every morning for about 30 days prior to the shooting." The owner of the construction business said he believed Alexis was angry over the parking problem outside the construction site, Seattle police said.
Alexis was booked into King County Jail on June 3, 2004, after making several attempts to find him, police records show.
Court records show he had a hearing and was released on the condition he not have contact with any of the construction workers. A message left for the attorney who represented him at that hearing, Raymond Connell, was not immediately returned.
Seattle police said Monday the case was referred to Seattle Municipal Court for charges of property damage and discharge of a firearm.
There's no record that he was ever prosecuted, and a spokeswoman for the Seattle City Attorney's Office, Kimberly Mills, said Monday that her office never received the report from police so did not review it for possible charges.
According to public documents, Alexis lived in Seattle in 2004 and 2005. He voted in 2004, and received several traffic violations in the Seattle area.
Nobody answered the door Monday afternoon at a home in south Seattle where Alexis lived at the time. The home is near the end of a dead-end street that backs up against Interstate 5, sits under heavy airplane traffic and is across from a park marred by graffiti.
Neighbors said two older women lived in the home. Juan Martinez, 32, lives next door and said he has had brief, friendly encounters with his neighbors but hasn't seen any male relatives at the home or heard of them mentioned. He's lived in the area for five years.
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