Aaron Alexis, the gunman behind Monday's Navy Yard shooting in Washington, D.C., displayed signs of psychological trouble before he killed 12 people.
The 34-year-old military contractor gave off warning signs of mental illness, experts told Metro, perhaps most notably through run-ins with law enforcement. Alexis allegedly shot out the tires of a man’s truck in Seattle in 2004 and claimed to have blacked out during the incident. He was arrested again in 2008 for disorderly conduct in DeKalb County, Ga., and again in 2010 in Fort Worth, Texas, for shooting his gun through the ceiling of his apartment – though he was never charged after he claimed he was simply cleaning his gun.
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In addition to his arrests, Alexis had also seemed increasingly agitated to his peers. He expressed frustration with his company, through which he worked as a contractor for the Navy. Alexis told his friends he felt the company was not treating him properly in terms of benefits and pay, according to ABC News. One close friend even told ABC that she suspected Alexis of purposely damaging her brand new car. Alexis’ best friend Nutpisit Suthamtewakul told USA Today that Alexis was paranoid and "always thought someone was trying to hurt him."
An anonymous Navy official told the Los Angeles Times that Alexis’ Navy record included “several unauthorized absences from duty, instances of insubordination and disorderly conduct, one instance of being absent without leave and several failed inspections.”
Psychologist Dr. Peter Langman, author of "Why Kids Kill: Inside the Minds of School Shooters,” told Metro that Alexis’ history of previous violent behavior coupled with his gun use made him particularly dangerous.
"That to me would be a red flag,” said Langman. “If he’s looking really agitated and he has owned guns and misused them in the past, that really increases the risk that his anger will take a violent turn.”
Langman said one common trait of mass killers is that they, like Alexis, feel wronged and want to take revenge for the perceived offense. “[The killers] feel like they’re the victim and they’re justified in taking revenge, even if the shooting has nothing to do with the original injustice,” Langman explained. “He felt victimized in the Navy and he didn’t go for the specific people who victimized him, he just went after random people somehow connected in his mind to the organization that served him the injustice.”
Dr. Kathy Seifert, an expert on mental health and criminal justice, said while the warning signs individually may not have been serious, their accumulation was a cause for concern. However, in many cases, as in Alexis’, the information was spread out over several different sources and it may have been difficult for one person to see the whole picture.
"The police had part of it, his employer had part of it, Veterans Affairs had a piece of it. … He had trouble in the military, so if we’re looking at the whole thing, we can see the pattern,” Seifert said. “When those risk factors start to add up is when they need an evaluation.”
Seifert said psychologists need to evaluate people who are at risk for violence differently than those who are not. “Basically, what you’re looking for is how well the person is functioning in his life, and if they’re having problems at work, at home and in the community,” she said.
Seifert said other signs include emotional outbursts, a history of aggression, anger issues and difficulty getting along with other people, and that a combination of these signs equal a big red flag.
Alexis reported hearing voices to Veterans Affairs, according to USA Today – a hallmark symptom of schizophrenia. Langman said hearing voices is also a symptom of other mental illnesses, but schizophrenia is a "good guess.” He said many of history's mass shooters have had undiagnosed schizophrenia.
“If he had schizophrenia, that could have really magnified his grievances,” said Langman. “It could have been a key factor.”
Seifert pointed out that if Alexis did have schizophrenia, which often manifests itself in the late teens to early twenties, nobody around him put the signs together. Alexis’ family said he was suffering from PTSD stemming from his time acting as a responder after 9/11, and Seifert said this is a possible explanation for his hearing voices, though schizophrenia is a more likely cause.
“People can have flashbacks of something that happened, and only a professional can tell you if it’s a flashback or a hallucination, but something going on in his head wasn’t right and he needed an evaluation and treatment,” she said. “The reality is that he didn’t get it, even though he went to the VA twice.”
Seifert added that though most people with trauma do not become violent, untreated trauma can lead to serious consequences and violence.
Many media outlets have also pointed out that Alexis stayed up late playing shooting video games. Langman said although violent video games have no serious bearing on the vast majority of the population, there are some people who are particularly vulnerable to influence from violent games and movies.
"If they’re feeling agitated and building their rage, it can be an imaginary preparation for what they’re eventually going to do in real life,” he said. "They get used to killings and shootings without feeling anything. In this case, it may have provided a little extra factor – a rehearsal and desensitizing for someone who was already on the edge.”
Both Seifert and Langman agree that one of the most important factors in preventing future violence is de-stigmatizing mental healthcare and raising awareness about mental health in the general population. “We all need to be better educated about what signs and symptoms we need to be worried about and get people immediate help; we need to educate families, supervisors, owners of business and the general public to recognize the difference between a little mental health problem and a big mental health problem,” said Seifert.
Langman said if people are worried that someone they know may commit an act of violence, they should ask them if they're thinking of hurting other people or themselves and refer them to mental health professionals if so. Otherwise, they can explain their concerns to local law enforcement and have police officers assess the situation.
Follow Andrea Park on Twitter: @andreapark