Shasta County deputy district attorney Eamon Fitzgerald called lead investigator on the murder case, Logan Stonehouse to the stand.
Stonehouse described his encounters with Mark the night Karen was found dead and the three interviews following, which totaled about 11 hours.
A short part of one of the interviews was shown. In it, Mark reacts to hearing part of the 911 call in which the prosecution says he admits killing his wife and using a curse word.
In the interview Mark tells detectives on the 911 call it's some, "creepy voice" and he never uses curse words.
Stonehouse testified Mark told him the last time he saw his wife alive was as she was walking down a hallway to go to bed on May 4th.
Mark, who slept in a separate bedroom due to his work schedule, said he was awoken later in the night by the sound of cats fighting. It was then he noticed a light on in Karen's room and found her lying face down in a pool of blood.
He said he heard a fluttering and a gurgling sound coming from her chest.
Mark also said he wiped blood from her face and arms before deputies arrived.
Nothing was found missing or out of place in Karen's room.
In cross examination, Ron Powell, Mark's attorney said Mark always willingly came forward for interviews, saying he wanted "to help."
Powell also discussed how Mark had been quick to come forward to talk about his out-of-state phone relationship with another woman.
Powell also questioned if any tests had been done to see if the people who claimed they heard Karen scream that night really could.
The jury has been dismissed for the rest of the week. The defense said they plan to present their case on Tuesday and they think they can wrap this thing up pretty quick, potentially in one day and they did say they plan to call Mark Duenas to the stand.