From Little Things Big Things Grow

Twice, before he shot and killed 12 people in a rampage at the Washington Navy Yard on Sept. 16, Aaron Alexis was arrested for discharging a firearm - once in his Ft. Worth apartment, and once outside his grandmother's home in Seattle. Neither time was he prosecuted for a crime. 

And in a related story:

Navy Yard gunman Aaron Alexis had sought treatment for insomnia in the emergency rooms of two Veterans Affairs hospitals in the past month, but he told doctors he was not depressed and was not thinking of harming others, federal officials said Wednesday.

And this:

Aaron Alexis sought medical help in the days before his shooting rampage at the Washington Navy Yard, leaving a trail of missed distress signals now under scrutiny in the massacre’s wake.

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