Investigators believe missing Thurston County couple was killed by tenant

Thurston County deputies went to the couple’s home for a welfare check on Nov. 13 after Koep failed to show up for work. Court documents say responding detectives found large pools of blood at the couple’s home, as well as signs that someone had attempted to clean it up.

“I believe it was indeed a dispute, a dispute between tenants. They own a property and he was a tenant,” said Pauline Dutton, Koep’s sister.

On Friday, investigators arrested the suspected killer while he was hiding along a trail not far from the murder site. KOMO News has not named the man because criminal charges have not yet been filed, but he appeared before a judge Monday where probable cause was found for two counts of premeditated murder . The suspect remains in custody without bail.

It appears Koep and Davido, who went by one name, were shot dead and then their bodies were loaded into the trunk of their car. Court documents say officers found a trail of blood from the couple’s home to the garage “which is believed to be where the trunk of the car was located.”

“The influence and legacy she leaves is incredible,” said Ann Rettemier, a patient and friend of Koep. “I cry all the time. I prayed all last week and I couldn’t even get the words out.”

Dutton said her sister immersed herself in each person’s health and was there for them spiritually and as a mentor outside of office visits.

“I’m so blessed to be able to hear that everyone is sharing these beautiful stories because they’re really comforting our family right now,” Dutton said.

According to court documents, the couple’s credit cards were used after they disappeared, and video showed the man making the transactions. Investigators conducted surveillance and arrested a man for identity theft. Court documents say the man was carrying a semi-automatic pistol in his pants pocket when he was taken into custody.

The man was eventually released due to lack of sufficient probable cause, but investigators learned that he was a tenant in a house owned by Davido. Deputies believed the tenant was suffering from mental health issues and had previously contacted law enforcement to complain that Davido was trying to evict him.

The Washington State Patrol Crime Lab then provided a match between the firearm taken from the suspect and the spent cartridges recovered at the murder scene.

Investigators located the suspect and took him into custody.

“I don’t think this man is stable and I hope he gets the help he needs. I want to hate him but we are a family of faith, and it’s not my job to hate and this doesn’t help the community,” Dutton said. “We just want to be representative of how my sister and her husband were. We’re going to continue to spread love and kindness.”