MOSCOW, Idaho -- We're learning more about the 28-year-old graduate student charged with the brutal murders of four University of Idaho students as they were sleeping.
Kohberger is a graduate student at Washington State University's Department of Criminal Justice and Criminology. The Idaho murder suspect had finished his first semester as a PhD student in the school's criminal justice program earlier in December.
Now, a Washington State University student who had Kohberger as a TA in his criminology class is shedding light on his personality in class and how his behavior changed after the Idaho murders took place.
"It was just like, totally jarring, totally shocking to realize that this person who had been grading my papers was allegedly this horrible murderer," Hayden Stinchfield told CNN.
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While his interactions with Kohberger were limited to the lecture hall, he said his grading style was "pretty strict."
"He'd be grading you on what he ended up calling a 'higher standard,'" Stinchfield said. "But what it really felt like to us was he was grading us like he would have graded himself as a Ph.D. student... We were all annoyed by him."
In fact, Stinchfield said his professor allowed the students to argue for better grades at one point in the semester to get a "courtroom experience."
"He brought in Bryan, and he was like, 'alright, go at him,'" Stinchfield said. "And he had Bryan stand up. And a few people were on his side because they wanted to keep their high grades... but for the most part, it was like half of a 150-person class just asking these real critical questions."
"It wasn't like yelling or anything, but it was certainly conflict," Stinchfield added.
The murders took place about a month before winter break, and that's when Stinchfield said his grading style took an abrupt turn.
"Around then, he started grading everybody just 100s," he said. "Pretty much if you turned something in, you were getting high marks and he stopped leaving notes."
Stinchfield described his behavior after the murders as "pre-occupied" and said he appeared less "well-kept" and had grown out his facial hair.
"The previous mental preoccupation that we had been noticing, where it was like he didn't really want to be there, that was at an all-time high," Stinchfield said. "He just didn't look like he was doing great."