AJ Armstrong trial: Presiding judge determining if robbery video should be admitted into evidence

HOUSTON, Texas (KTRK) -- Evidence that will be seen in the third capital murder trial for AJ Armstrong was presented on Thursday. Text messages between Armstrong and his parents in the months leading up to their murders, his police interrogation, and autopsy photos of Dawn and Antonio Sr. were admitted during a pre-trial hearing.

But there's one surveillance video clip Judge Kelli Johnson has yet to decide if she'll allow jurors to see.

Twelve days after the murders, the black and white video shows what appears to be two men breaking into a gym owned by the Armstrongs in Bellaire and stealing two computer monitors.

The defense attorney for Armstrong, Rick DeToto, argued that the video is evidence there could be an "alternative perpetrator." Armstrong was in jail, already charged with his parents' murder, when the break-in happened.

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Prosecutors fired back, saying there was no connection between the robbery and the murders.

In the capital murder, "nothing was taken from the home," Assistant District Attorney Ryan Trask pointed out.

Dawn and Antonio Sr. were shot to death in July 2016. Their son was arrested and charged hours after their murders. In two separate exclusive interviews with ABC13, Armstrong has maintained his innocence.

Since the first trial, the defense has suggested Armstrong's older half-brother, Josh Armstrong, who has a mental illness, could be the real killer.

DeToto said the evidence showing that has "gotten stronger."

"Josh Armstrong is not on trial here," Trask argued.

Prosecutors also contended no one has ever identified either of the two people seen in the surveillance video as Josh.

In Armstrong's first trial, the video was seen by the jury. In the second trial, the defense changed its strategy and didn't use it.

RELATED: Jury picked for AJ Armstrong's 3rd murder trial set to start Monday

Judge Johnson is expected to rule on Monday, June 5, before jurors are seated on whether or not the video will be evidence in the new trial.

Opening statements will begin with 45 minutes for prosecutors as they lay out their theory of how A.J. Armstrong allegedly murdered his parents when he was 16 years old.

The defense will have the same amount of time to show why Armstrong is not the killer.

The jury of 12 and four alternates was picked Wednesday after an in-depth, three-week selection process.

The trial is expected to last between two and three weeks.

If Armstrong is found guilty, he'll be automatically sentenced to life in prison with the possibility of parole after 40 years.

See more of ABC13's seven-year coverage on A.J. Armstrong's murder trial.

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