DELPHI, Ind. — Richard Allen’s defense team called forensic and mental health experts to the stand Tuesday morning.

They aggressively sought to cast doubt on the state’s argument that Allen killed Libby German and Abby Williams.

The girls were found dead with their throats slit near the Monon High Bridge in Delphi, Indiana, 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. He had previously stated that he was on the road to the bridge several times on the day of the murders.

Blair said he saw a vehicle near the trail, backing into the area near the old Child Protective Services building. He said it caught his attention because it “didn’t park the way other people parked.”

Stating that the vehicle was a four-door sedan, Blair said that he could not remember exactly what color it was, but that it was not brightly colored. He also stated that the car was an old model vehicle.

The state says they believe Allen tracked down his 2016 black Ford Focus on the day of the murders.

The juror asked Blair if the car belonged to someone who worked at the CPS building. Blair said the building appeared abandoned.

The defense also stated that Dr. He also called out Stuart Grassian. He is 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 that when people are kept in solitary confinement for a long period of time, they can become “confused, disoriented” and “extremely lonely” as they have little opportunity for stimulation.

Grassian said he never visited Allen’s cell but saw the video provided by the defense.

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Defense attorney Brad Rozzi asked Grassian if he noticed signs of delirium in Allen’s phone calls with other people. “Absolutely yes,” Grassian replied.

“Your memory may change over time,” Grassian continued. He added that this was “entirely consistent” with Allen’s symptoms.

The jury asked several Grassians a few questions. The first was whether psychotic behavior could return to normal after a person was removed from a situation.

“Generally speaking, yes,” Grassian replied.

Another juror asked Grassian if he believed someone described as normal could become psychotic six months later. Grassian said, “Absolutely. I’ve seen it happen.” he said.

The defense then asked Dr. He called Erin Warren to the stand. He had a job doing crime scene reconstruction and worked in the firearms identification unit of the Tennessee Bureau of Investigation.

The defense asked Warren to review Melissa Oberg’s work. He is the former Indiana State Police crime lab technician who examined the unspent bullet found at the murder scene and compared it to Allen’s gun.

Oberg’s analysis revealed that the crime scene investigation involved Allen’s gun.

This is the state’s key piece of evidence connecting Allen to Libby and Abby’s deaths.

Warren reviewed the results of the ISP test and told the jury he viewed them as an “apples-to-oranges comparison.” He said Oberg came to that conclusion because he compared the first bullet, which was not fired, again, to a bullet fired from Allen’s gun.

When Oberg took the stand, he told the court that “a throw signal is a throw sign” regardless of whether the projectile is repeated or not.

Warren disagreed with testimony that said the laboratory should have identified instrument markings under the circumstances in which lead was found.

Jurors had 15 questions for Warren about the cartridge’s testing method; this was far more questions than most witnesses received from the jury.

The trial is expected to continue Tuesday afternoon.