In August 2023, Armstrong was convicted of shooting and killing his parents, Dawn and Antonio Sr., back in 2016 as they slept in their southwest Houston home.
Armstrong was 16 years old at the time. Now a 24-year-old father, he is appealing his conviction.
The DA's letter, filed in the last 24 hours, explained that some of the language used to describe the results of the DNA testing done in Armstrong's case could be imprecise. The letter does not say there are errors with the DNA testing itself.
"We are aware of (Houston Forensic Science's Center's) nonconformance report, as we sent defense notice of it," the HCDAO said in a statement to Eyewitness News. "It is our understanding that while language within any supplemental report may change, the overall results and conclusions will not.
We have also reached out to Armstrong's appellate attorney for a reaction to the news. ABC13 has yet to hear back.
Armstrong is currently serving life in prison at the Robertson Unit in Abilene, Texas, with the possibility of parole after 40 years.
The twists and turns of this case have spanned eight years. ABC13 covers it all in our in-depth documentary, Texas True Crime: All American Killer. Watch it now wherever you stream ABC13.
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