The suspect in the shooting outside a North Austin Target had a history of mental health issues and frequent run-ins with law enforcement since at least 2012, according to a police statement and court records from Travis and Williamson counties.
Ethan Nieneker, a 32-year-old white man, spent time behind bars in 2016 and 2017 for family violence, driving while intoxicated and violating the terms of his bond or protective order, court records show.
At least two other family violence charges in Travis County were dismissed; the last charge from 2019 was dismissed three years ago because the victim was unable to be contacted. Nieneker was also charged with marijuana possession and vandalism.
Nieneker is accused of fatally shooting Adam Chow and his 4-year-old granddaughter in a Target parking lot on Monday afternoon. A third victim, Hector Leopoldo Martinez Machuca, was transported to the hospital where he was later pronounced dead.
Nieneker was charged with two counts of capital murder and first degree felony murder, APD Sgt. Nathan Sexton said at a news conference Tuesday. He could face additional charges.
The suspect used a handgun that he got through his family, Sexton said. Generally, people convicted of domestic violence cannot legally possess firearms under federal law. It was unclear whether any family member will face charges.
APD is investigating whether he was under the influence of drugs or alcohol at the time.
Austin Police Chief Lisa Davis said the victims were chosen at random and that there were "some serious failures here" in reference to the mental health system.
On Monday, Davis said Nieneker has previously been held in emergency detention. These holds occur when there is evidence of "imminent, substantial risk of serious harm to self or others."
A coworker who asked not to be named for fear of losing their job said Nieneker had a noticeable change in behavior during his shift at a restaurant Saturday evening.
"He started to ramble on about how in the past few days he has had a revelation and felt as though he was chosen and felt like a new man," the coworker told KUT News, adding that Nieneker said he had not eaten in several days "in an attempt to become closer to his higher power."
"It just struck me as very manic," the coworker said. "The way he was speaking was kind of fast and declarative. It struck me as very concerning just because it was such a stark difference from the Ethan I had worked with the previous weekend."
KUT News' Syeda Hasan contributed to this report.
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