Son of ex-NFL player found guilty of killing parents, sentenced to life in prison

The son of a former NFL player was found guilty of capital murder in the killing of his parents when he was 16, a Texas grand jury determined on Wednesday.

Antonio “A.J.” Armstrong Jr. was sentenced to life in prison without parole after 40 years, according to FOX 26 Houston.

Armstrong was charged in 2016 with the murders of Antonio and Dawn Armstrong. Prosecutors said Armstrong shot and killed his parents inside their Bellaire townhome. Dawn Armstrong was pronounced dead at the scene and Antonio Armstrong died in a hospital with a gunshot wound to the head.

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Antonio Armstrong, Jr., stands outside the courtroom following the day’s testimony in his trial on Monday, April 22, 2019, in Houston. (Brett Comer/Houston Chronicle via Getty Images)

There were two mistrials before the conviction this week. The jury was hung in a deadlock in 2019, and in 2022, they could not agree on a verdict.

Authorities at the time said the son’s story about a masked intruder did not add up, and an investigation failed to find any evidence of a forced entry. A portion of the 2019 trial focused on A.J. Armstrong’s call to 911, saying “it’s all my fault,” according to FOX 26 Houston.

Prosecutors argued in the first trial that Armstrong put a pillow over his parents’ faces and shot them both – a claim Armstrong denied. Prosecutors also said that before the murders took place, Armstrong fired a practice shot into his bedroom floor and also claimed Armstrong tried to light the house on fire and researched how to rig a vehicle in order for it to explode when it turns on.

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Antonio Armstrong, Jr., stands outside the courtroom following the day’s testimony in his trial on Monday, April 22, 2019, in Houston. (Brett Comer/Houston Chronicle via Getty Images)

Armstrong’s relationship with his parents was reportedly strained before the killings.

The third trial honed in on the family’s alarm system inside the house. Home security representatives testified to the exact timings of motion sensors ticking off and how it was linked to the murders. A motion sensor near the parents’ bedroom ticked off at 1:09 a.m. Another sensor ticked off at 1:25 a.m. near where the murder weapon was found, and after 911 was called, the alarm was disarmed at 1:56 a.m.

The third trial also mentioned blood specks on Armstrong’s shirt at the time he was arrested. The Harris County district attorney said two drops of blood belonging to Antonio Armstrong Sr. were found on the back under a nametag sticker the police put on A.J.’s shirt when he was initially arrested. Forensic officials initially said no DNA evidence was reported to be found, according to the station.

Armstrong reportedly filed a lawsuit against the City of Houston over the blood specks revelation.

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Antonio Armstrong Sr. with the 49ers. (Rick Doyle / Getty Images)

Antonio Armstrong was a standout linebacker at Texas A&M University before briefly playing for the San Francisco 49ers and Miami Dolphins.

The Associated Press contributed to this report.