Bryan Kohberger Had Help Committing Idaho Murders: Expert Witness

Dr. Brent Turvy, a crime scene reconstruction expert for the defense, believed it was 'likely' there were two people and two weapons involved. His report cited that Ethan Chapen would not have remained in bed while Xanna Kernodal was attacked, suggesting a second assailant. He also pointed to multiple types of lethal force used against Kaylee Goncalves and the simultaneous attacks on Ethan and Xanna.

Dr. Turvy's report stated, 'It is not reasonable to think that Ethan would have remained in his bed after waking up or being awake while Zana was being attacked in front of him. This evidence and context begin to suggest the existence of a second attacker.' He also noted, 'Multiple weapons were used against Kaye, that multiple types of lethal force were used against Kaye, and that Ethan and Zanna appear to have been attacked at the same time.'

State expert Pette Sutton and forensic death investigator Joseph Scott Morgan countered that a single perpetrator could use multiple weapons or apply various types of lethal force with one weapon. Morgan specifically detailed how a KBAR combat knife, a utility knife, could be used for stabbing, blunt force trauma (using the handle or side), and incising, explaining Kaylee Goncalves' diverse injuries.

Pette Sutton commented, 'One assailant could contain two people in close proximity to each other, especially if the assailant is armed. A single perpetrator can certainly use more than one weapon and can use multiple types of lethal force.' Joseph Scott Morgan elaborated, 'The KBAR combat knife is a utility knife... it has multiple utilities... it is meant to kill, but it is also meant to be used in the field.' He added, 'The thing can be actually turned on its side and used to thrust with like in a punching motion. It can use to hammer down if you invert it and start to slam it down onto somebody's face.'

Dr. Turvy argued that the extensive blood transfer and precautionary acts (like cleaning hands, feet, clothing, and disposing of items) would have required 'perhaps hours' at the scene, contradicting the state's timeline of less than 15-20 minutes. Pette Sutton, however, stated that 'washing or wiping hands takes little time' and 'removal of protective clothing and shoe coverings takes seconds.'

Dr. Turvy's report detailed, 'All of this would have required an extensive amount of time at the scene to clean, perhaps hours, which is inconsistent with the state's theory that these crimes were committed within a time interval less than 15 to 20 minutes subsequent to 4:00 a.m.' Sutton's rebuttal: 'Washing or wiping hands takes little time, especially if preparations for cleaning are made beforehand. Removal of protective clothing and shoe coverings takes seconds.'

Prosecutor Bill Thompson explained that Kohberger was not compelled to provide details of the crime during his guilty plea. This decision was made to ensure a 'solid, sustainable guilty plea' because, in their experience and based on FBI profiler advice, defendants often minimize or cannot be trusted for truthfulness when asked to explain such bizarre crimes.

Bill Thompson stated, 'We made a decision that we wanted to make sure that the guilty plea itself was solid if he was going to plead guilty. Our experience... is that frequently when defendants are being asked to explain... they start to minimize... they can't be trusted for the truthfulness of what they say.' He also cited FBI profilers who advised that 'even if we were to get the person who committed these crimes to try to explain why it happened, that it wouldn't make sense to normal people like us.'

The defense planned to highlight unknown male DNA samples found on a handrail inside the house and a glove outside, which were never run through CODIS. The state deemed these samples 'not probative' because Kohberger's DNA on the knife sheath was considered direct evidence. Joseph Scott Morgan argued this was a significant oversight, as it fuels speculation and leaves doubt.

The host stated, 'These unknown male DNA samples that were never run through COS and one was found on a handrail inside the house and then one was found on a glove outside the house.' The state's reasoning was that 'the KBAR knife sheath DNA was probative... These other other samples were not considered probative, so we didn't enter them into COTUS.' Joseph Scott Morgan commented, 'I think that it would have been worth their time to have plugged these in... this could have been cleared up if they had been plugged in and really pursued.'