Prosecutors say AJ Armstrong's brother's paranoia does not make him killer in 2016 murders

HOUSTON, Texas (KTRK) -- July 28, 2016, was a night like any other night for Josh Armstrong.

That's how his then-girlfriend, Hannah Pilon, described it to the jury, as she sat across the courtroom from Josh's younger, half-brother, A.J. Armstrong, on trial a third time for allegedly killing their parents.

Josh is the biological son of Dawn Armstrong and was adopted as a child by Antonio Armstrong Sr.

Pilon testified she went to sleep between 10 p.m. to 11 p.m. in Josh Armstrong's one-bedroom apartment, less than a mile from the Armstrong home on Palmetto Street in southwest Houston. She said Josh stayed up playing video games with his cousin, and the next thing she remembers is "frantically" being woken up by Josh.

"Something was really wrong. (He was) scared, worried, shook me awake. I was really confused," Pilon testified.

She said Josh grabbed a "big shotgun" and ran out of the apartment. At some point, she said Josh told her A.J. had called and said someone had shot their parents. Pilon called 911.

"Then the sadness turned into paranoia," Pilon said on the stand, her eyes welling up.

A few months after the murders, Josh "completely changed," she said. "There were no signs of mental illness or paranoia before the murders-and I want to be completely clear about that," she said, looking directly at jurors. "He was the most happy, loving person I had ever known."

Then, Josh made "the list," Pilon said-a list of people he thought could be the killer. He obsessed over trying to solve the murders, she said in court. Pilon says she was on that list, despite trying to reason with Josh that she couldn't have killed the Armstrongs because she was asleep in his apartment.

He was slipping away, she told the jury.

Pilon said shortly after the murders, Josh convinced her to leave Texas for Colorado because he was terrified someone was after them. She said his paranoia was based on the note left in the Armstrongs' kitchen next to the gun that read: "I'VE BEEN WATCHING YOU FOR A LONG TIME. COME GET ME!"

"The note played a big part of him being scared," Pilon testified.

She stayed with Josh a year after the murders, despite his mental spiral, she said. "But it got worse every day. It got so bad I had to leave."

Nearly five months after the murders, Josh, 21 at the time, checked himself into Ben Taub Hospital for a psychiatric evaluation, according to medical records prosecutors showed the jury on day eight of trial.

According to that paperwork, Josh's "symptoms started six months after parents were murdered... symptoms include anxiety, paranoia, substance use. Patient admits to feeling suicidal." The documents stated Josh went to the hospital voluntarily at the urging of his grandparents and did not believe his brother murdered their parents. "The paranoia seems related to the trauma," it was noted in the records.

Prosecutors say Josh had a psychotic breakdown because his parents were murdered.

But the defense has long argued, Josh started spiraling mentally months before the murders-and he could be the real killer.

When HPD Sgt. Kenneth Daignault took the stand, defense attorney Rick DeToto attacked police for not investigating Josh Armstrong further.

"The evidence didn't lead us there," Daignault said.

"You zeroed in on A.J.," DeToto yelled in court. "Who was responsible to talking to Josh? Why didn't anyone interview neighbors?"

"The evidence did not lead us to Josh," Daignault repeated. "He was never a suspect."

Josh was photographed at the scene, his hands bagged and tested for gunshot residue. No GSR was found on Josh or A.J. Armstrong. A GSR expert previously testified that is often the case when firing a .22 caliber pistol like the one used in this double-homicide.

For more than two hours, Daignault testified.

Prosecutor Ryan Trask once again took the jury through A.J. Armstrong's audio recorded interview with Daignault and HPD Sgt. Jimmy Dodson, hours after the murders.

During that interview, Armstrong acknowledged to the detectives that the house alarm didn't go off, so he didn't think the killer left through a door but instead could have gone out a window.

Daignault said he checked every window and exterior screen at the house after interviewing Armstrong. All of them were secure and locked from the inside, the blinds, undisturbed, he testified.

Armstrong never asked for details about the murder, about what was written on the note after detectives told them one was left at the scene, or about how his parents were doing, Daignault told the jury.

When Daignault said he told the then-16-year-old he'd be charged with murder, Daignault said, "He (Armstrong) responded: 'What evidence you got?'"

Trask pointed out that Armstrong called 911 at 1:40 a.m. to say he heard shots from his parents' bedroom on the second floor. At 1:46 a.m., the first police officers arrived.

"Pillows over their heads, write note, open five drawers," Trask wrote in bullet points on a large white pad in front of the jury, illustrating all things that "would have had to be done in six minutes."

On Thursday, we expect to hear more testimony about Josh's mental state from doctors who have observed him and possibly, see more of his medical records.

"Is somebody a suspect just because they have (a) mental illness?" Trask asked Daignault at the end of the testimony.

"No," Daignault replied.

The state will likely rest its case Thursday, the ninth day of testimony. So far, they've introduced 25 witnesses in their case.

Courtney Fischer is bringing all the latest updates on AJ Armstrong's third murder trial on Facebook, Twitter and Instagram.