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

They continued to aggressively try and 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. She had earlier testified that she was on the path leading to the bridge several times on the day of the murders.

Blair said he saw a vehicle near the trail, it was turned into the area near the old child protective services building. She said she stayed in it because “it wasn’t parked like other people park.”

Blair described the vehicle as a four-door sedan, could not remember exactly what color it was, but said it was not brightly colored. She also described the car as an older model vehicle.

The state says they believe Allen was driving his black 2016 Ford Focus on the route on the day of the murders.

A juror asked Blair if she thought the car might have belonged to someone who worked at the CPS building, Blair said the building looked abandoned.

The defense also called Dr. Stuart Grassian. He is a psychiatrist specializing in isolation, false memories and false confessions.

Grassian listened to Allen’s calls from prison and read the transcripts of other inmates.

He told the court that when people are kept in isolation for a long period of time, they can become “confused, disoriented” and “extremely lonely” because there are minimal opportunities for stimulation.

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

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

Grassian went on to say, “Your memory can change over time.” He added that this was “perfectly consistent” with Allen’s symptoms.

The jury asked Grassian several questions. One was whether psychotic behavior can return to normal after the person is removed from a situation?

Grassian replied, “In general, yes.”

Another juror asked Grassian if he thought someone described as normal could become psychotic after six months? Grassian said, “Absolutely.” I saw how it happened.

The defense then called Dr. Erin Warren to the stand. He owns a crime scene reconstruction business and worked for the Tennessee Bureau of Investigation in the firearms identification unit.

The defense asked Warren to review Melissa Oberg’s work. She is the former Indiana State Police technician who examined the unexpended round found at the crime scene and compared it to Allen’s gun.

Oberg’s analysis found that the crime scene had been rifled through by Allen’s gun.

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

Warren reviewed the ISP test results and told the jury he considered them to be an “apples to oranges” comparison. He said he came to that conclusion because Oberg compared the initial round, which was cycled, not fired, to a bullet fired from Allen’s gun.

When Oberg was on the stand, she told the court that “an ejector mark was an ejector mark” regardless of whether a round was cycled or fired.

Warren disputed that testimony saying the lab was supposed to identify the tool marks under the same conditions the bullet was found.

Jurors had 15 questions for Warren about the cartridge testing method, which was significantly more questions than most of the jury witnesses received.

Court is expected to resume on Tuesday afternoon.