They continued to aggressively try and cast doubt on the state's argument that Allen murdered Libby German and Abby Williams.
The girls were found dead with their throats slit near the Monon High Bridge in Delphi, Indiana back in February 2017.
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The video in the player above is from a previous report.
Betsy Blair was the first witness called to the stand. She testified earlier that she was on the trail leading to the bridge multiple times on the day of the murders.
Blair said she saw one vehicle near the trail, it was backed into the area near the old Child Protective Services building. She said it stuck out to her because it was "not parked how other people park".
Blair described the vehicle as a four-door sedan, she couldn't remember exactly what color it was, but she said it wasn't brightly colored. She also described the car as an older model vehicle.
The state says they believe Allen drove his 2016 black Ford Focus to the trail the day of the murders.
A juror asked Blair if she thought the car could've belonged to someone working at the CPS building, Blair said the building looked abandoned.
The defense also called Dr. Stuart Grassian. He is s a psychiatrist who specializes in solitary confinement, false memories, and false confessions.
Grassian listened to Allen's calls from prison and read transcripts from other inmates.
He told the court, when people are held in solitary confinement for a long period of time, they can become "confused, disoriented" and "extremely lonely" since there is minimal opportunities for stimulation.
Grassian said he never visited Allen's cell but saw video provided by the defense.
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Defense attorney Brad Rozzi asked Grassian if he noticed symptoms of delirium on Allen's phone calls to other people, Grassian responded, "Absolutely yes."
Grassian went on to say, "Your memory can shift over time." He added this was "perfectly consistent" with Allen's symptoms.
The jury asked several Grassian several questions. One was if psychotic behavior can go back to normal after the person is removed from a situation?
Grassian responded, "Generally, yes."
Another juror asked Grassian if he believes someone described as normal can become psychotic after six months? Grassian said, "Absolutely. I've seen it happen."
The defense then called Dr. Erin Warren to the stand. He owns a business dealing with crime scene reconstruction and worked for the Tennessee Bureau of Investigations in the firearm identification unit.
The defense asked Warren to review the work of Melissa Oberg. She is the former Indiana State Police crime lab technician who examined the unspent round found at the murder scene and compared it to Allen's gun.
Oberg's analysis found the crime scene round had been cycled through Allen's gun.
This is the state's key piece of evidence tying Allen to Libby and Abby's deaths.
Warren reviewed the results of ISP testing, and he told the jury he considered them to be an "apples to oranges" comparison. He said he came to this conclusion because Oberg compared the initial round, which had been cycled, not fired, to a bullet fired from Allen's gun.
When Oberg was on the stand, she told the court an "ejector mark was an ejector mark" regardless of whether a round was cycled or fired.
Warren disputed that testimony saying the lab needed to identify toolmarks under the same conditions in which the bullet was found.
Jurors had 15 questions for Warren about the testing method on the cartridge, which was notably more questions than most witnesses have gotten from the jury.
Court is expected to resume on Tuesday afternoon.