AJ Armstrong 3rd trial: Prosecutors build replica bedroom, use mannequins as stand

HOUSTON, Texas (KTRK) -- Two mannequins laid on top of a wooden frame constructed to look like a king-size mattress, covered in a beige sheet, in the middle of Judge Kelli Johnson's courtroom.

That dramatic scene on day six of AJ Amstrong's capital murder trial drew the largest courtroom audience since trial began one week ago. Every seat seemed to be taken on Monday.

The female mannequin, dressed in a black nightgown, was positioned laying on her left side, similar to Dawn Armstrong the night of the murders, as was the male mannequin, similar Antonio Sr. He was dressed in pants and a black T-shirt. This was what the killer would have encountered in the early morning hours of July 29, 2016, according to prosecutors.

Dawn was killed instantly when she was shot twice behind her ear, while Antonio Sr. died a slow death after he was shot once, investigators say.

While defense attorney Rick DeToto argued the demonstration shouldn't be allowed in trial, Johnson ruled the jury would see it.

Celestina Rossi, a renowned crime scene reconstruction and blood spatter expert, testified that whoever shot the Armstrongs wouldn't have any blood on them based on her analysis of the scene.

Investigators have previously testified that no blood spatter was found on AJ Armstrong's clothing or body.

Prosecutor John Jordan stood behind the Dawn mannequin, pointing the gun used to kill her - the .22 caliber pistol in evidence - holding the muzzle 2.5 feet from her body, as Rossi measured the distance with a tape measure.

The medical examiner previously testified the shooter stood between two and a half to three feet from the Armstrongs, based on their blood stipple.

Rossi testified she believed Dawn was shot first, two times. Then, the killer fired a third shot, missing the Armstrongs. It went into a pillow placed between the couple, Rossi said, then went into the headboard.

"So then, a fourth shot?" Jordan asked Rossi.

"I believe so," Rossi answered.

Rossi testified she thought that fourth shot was the bullet that went into the top of Antonio Sr.'s head. This was the first time we've heard the theory that four shots were fired. Crime scene investigators only collected three shell casings from the primary suite the morning of their investigation.

With the standard king-size bed frame in the middle of the courtroom, Jordan also demonstrated how, if the killer had not come into the Armstrong's bedroom already in possession of Antonio Sr.'s gun, the shooter would have had to walk around the front of the bed, open Antonio Sr.'s bottom drawer nightstand, open his gun box, walk back to the other side of the bed, stand behind Dawn, and fire.

Prosecutors also reconstructed a to-scale model of the Armstrong stairs that led from the third floor, where AJ Armstrong's bedroom was located, to the second floor, where his parents slept.

During his police interrogation, Armstrong told detectives he saw a "Black man" who was wearing a "ski mask" running away while Armstrong was on the stairs, though he didn't detail where exactly he stood. Armstrong told investigators he couldn't describe the person more than that.

As Jordan stood on the top step, 53 inches from the ground, he looked toward the jurors. The staircase was positioned 3 feet and 3 inches from the jury box, which is the same width of the hallway in the Armstrong house. One by one, jurors stood directly in front of Jordan to decide whether or not they believe Armstrong would have gotten a good look at an "intruder" he says broke in and murdered his parents.

Before the dramatics of the king-size bed and staircase replicas, prosecutors introduced more of Armstrong's cellphone data, marrying it to a timeline of the Armstrong security system.

They showed the jury when Armstrong's iPhone display went on and off, something that "indicates the user was manipulating the phone, moving it around," Nathan Gates, the Harris County DA's digital forensic investigator, said. "Possibly using it for ambient lighting."

At 1:02 a.m., Gates said data extracted from Armstrong's phone showed he stopped using Instagram and his phone was locked. At 1:04 a.m., the phone was plugged in. At 1:08 a.m., Armstrong's phone was unplugged and the display went on.

At 1:09 a.m., prosecutor Ryan Trask reminded jurors the alarm records show the upstairs motion detector activated. That motion sensor is positioned outside Dawn and Antonio Sr.'s bedroom.

Between 1:16 a.m. and 1:24 a.m., Armstrong's iPhone display went on and off several times. At 1:25 a.m., the living room motion detector on the first floor was activated. There was no activity on Armstrong's phone until 1:40 a.m. when Armstrong called 911.

"Either you put it in your pocket or put it face down," Gates told jurors when asked to describe a situation when the phone display remains off.

DeToto pointed out Armstrong had been texting with his girlfriend, "acting lovey-dovey, like a normal teenager" minutes before his phone was plugged in and locked.

The defense also tried to poke holes in the state's theory of how blood ended up on the back of the Houston Police Department sticker put on Armstrong when he was taken to HPD headquarters for his interrogation hours after the murders.

Armstrong's T-shirt, pants, and sandals were collected that day by crime scene investigator Andrew Barr, the state's 18th witness to take the stand. Barr testified he saw no blood on Armstrong's clothes on July 29, 2016, saying he packaged the shirt and pants together and submitted the items to the property room.

Nearly seven years later, on June 2, 2023, days before Armstrong's third trial was supposed to start, Rossi, Barr, and a third investigator went to the property room because Rossi had asked to see the blood-stained pillows from the Armstrong bed.

On Monday, jurors watched the surveillance video of them in the property room on that day.

Video showed the investigators unpacking Armstrong's clothing, and Rossi peeling back the HPD sticker on Armstrong's T-shirt. Barr said they found what looked like two blood stains on the back of the badge, and a hemostick test confirmed it to be "presumptive blood." DNA testing was ordered to confirm whose blood it could be, Barr said.

DeToto attacked the new evidence.

"If there wasn't blood when you checked it, but now there is, that could be cross contamination!" DeToto said. "Textbook, 101, cross contamination when the shirt touches the pants."

Barr said it was standard practice to package both pieces of clothing together because "they came from the same source."

The state has questioned 19 witnesses over the past six days, nearing the end of their case. Defense is expected to start showing the jury what they think happened the middle to the end of the week.

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