Still no verdict after 4 hours of deliberation in AJ Armstrong's capital murder retrial on Monday

HOUSTON, Texas (KTRK) -- A.J. Armstrong walked out of court Monday surrounded by his grandmothers, girlfriend, family and friends, as jurors have yet to reach a verdict after their first day of deliberation.

Closing arguments lasted more than three hours.

Prosecutors began by talking about the importance of the Armstrong home security system, citing the alarm records prove the killer had to have come from inside the Armstrong home.

"It makes no sense someone outside the household would bust into the house with the alarm on, peruse the house, find the homeowner's gun, shoot the homeowner, go downstairs, write a note, lock up the house -- it just doesn't make sense," prosecutor Ryan Trask told jurors.

Trask held up a poster outlining A.J.'s cell phone activity on the morning of the murder, July 29, 2016. The records show A.J.'s cell phone activity stopped at 1:02 a.m.

"The only time (A.J.) was not on his phone was in the 38-minute window when his parents were getting murdered," Trask said.

At 1:09 a.m., the second floor motion detector, on the same floor where Dawn and Antonio Sr. slept, went off. A.J.'s bedroom was located on the third floor. The first-floor living room motion sensor was activated at 1:25 a.m., according to the alarm records. A.J. himself called 911 at 1:40 a.m..

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But A.J.'s attorneys showed jurors, the ADT house alarm records had errors 77 times in the three weeks leading up to the murders.

"The alarm records are that -- garbage. They are garbage," said defense attorney Chris Collings, throwing stacks of alarm records into a trash can for dramatic effect. "How many errors, how many mistakes, how many false reportings do you have to have? A.J. deserves to have his future decided on something more than records that are garbage."

Both prosecutors and defense attorneys revisited the text messages between A.J. and his parents.

"The reason we showed you those text messages was so you could see what the victims thought of (A.J.)," Trask said to the jurors.

Over the course of the last three weeks, jurors were shown dozens of texts between A.J. and his parents, which show Dawn and Antonio Sr. frustrated with their son over failing grades, lying about being out with his girlfriend, and smoking in the house.

"He was engaging in extremely disruptive behavior and he did it with a smile on his face," said Trask, talking about the weeks leading up to the murders.

"Throughout all those texts, when his mom and dad are getting on him about all the stuff that's going on, does he ever get angry? No," A.J.'s attorney, Rick DeToto told jurors. "Please go through all of (the text messages) -- not just the bad ones."

Thousands of pages of text message records were introduced into evidence during the trial. DeToto argued those records prove A.J. is not a cold-blooded killer because, minutes before the murders, he was texting with his girlfriend.

"A.J. was having kissy faces with his girlfriend. He's texting her: I love you. I miss you. Is that the state of mind of a killer?" DeToto said.

DeToto told jurors Houston police made up their minds within 11 minutes of being on the murder scene, that A.J. was the killer, without investigating anyone else.

"There was no gunshot residue, no blood, no fingerprints, no DNA, no nothing -- so as that disease spread through the homicide investigators, it started to shape how they looked at this case," DeToto said.

The defense has long said A.J.'s older half-brother, Josh , could have been the killer. Josh had dropped out of college and was living back in Houston, at an apartment near his parent's house on Palmetto. According to A.J.'s cell phone records, Josh was the first person A.J. called after calling 911. Josh showed up at the murder scene minutes later.

Josh suffered a psychotic breakdown in the years after his parents' murders, according to his medical records, published into evidence.

"We are not trying to stigmatize Josh. I feel sorry for that young man. The allegations by the district attorney's office that we're picking on him for his mental illness -- no way," DeToto said.

"What kind of desperate, Hail Mary attempt is this? They have totally missed the mark in understanding mental illness and how it played in this case," Trask told jurors.

A.J.'s attorneys argued Josh was starting to spiral before the murders -- and that could have led to him killing Dawn and Antonio Sr.. But prosecutors say it's clear Josh became severely mentally ill because of the traumatic event of living through his parents' murders.

"There were no signs of mental illness before the murders," Jordan said to the jury. "Let me say that again. There were no signs to anyone of mental illness before these murders."

While both sides fought to make their case, A.J. sat with his head down, writing on a yellow legal pad. He did not show emotion, remained calm, as he did for most of the trial.

DeToto ended his arguments standing in front of the jury box, motioning across the room towards A.J.. "He's in your hands now," DeToto said. "You have a very important decision to make. Give him back to us. Give him back to his family."

Jordan was the last to address the jury. He put a text message from Dawn to A.J. on the projector for the court to read.

"I know you left. The alarm doesn't lie. You lied. I can show you," read the text from Dawn to her son. It was sent in the days leading up to her murder, Jordan said.

"How appropriate that six years later, the last words of this trial would come from Dawn Armstrong. The woman who believed in justice and holding her son accountable," said Jordan. "There are no words I can say. No phrases I can use that are more powerful, more appropriate, or more damning, than that text message."

The jury is sequestered during deliberations. The judge has taken their cell phones and removed the TVs from their hotel rooms so they have no way to access information on the case. Day two of deliberations start Tuesday at 9 a.m.. Eyewitness News will update you as soon as a verdict is reached.

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