For seven years, Armstrong and his team fought to show he was not the killer. He first shared his story with Eyewitness News in 2018, claiming an intruder killed his parents. He saw the "masked man" run from the scene.
Armstrong's first two capital murder trials ended with hung juries, but in August 2023, a third jury convicted Armstrong of capital murder.
This case captivated a city, with twist after twist in the investigation.
Now, for the first time, and only on ABC 13, you'll hear from witnesses pivotal in putting Armstrong in prison, the former detective who interrogated the teen hours after the murders, and the bloodstain pattern analyst who explained how Armstrong committed the murders.
You'll hear Armstrong's own words: his 911 call and police interview, and see how prosecutors transformed the courtroom into the crime scene during trial.
We'll walk you through what prosecutors argued Armstrong was doing on his phone in the minutes leading up to the murders, and why they say Armstrong's iPhone activity fit with the home security system records "like a puzzle," proving he was the killer.
Armstrong's family has supported him from day one, believing he is innocent.
Armstrong, now 23, is serving life in prison in Abilene, Texas at the Robertson Unit, west of Dallas. It's a six-hour drive from his wife and young son in Houston.
He's appealing his conviction. Armstrong will be 63 years old when he's up for parole in 2063.
Watch Texas True Crime: All American Killer wherever you stream ABC 13.
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