DENVER (CBS4) – Michael Close pleaded not guilty by reason of insanity in the shooting death of Isabella Thallas in Denver’s Ballpark neighborhood last summer, according to Thallas’ family. Close is accused of killing Thallas and also shooting her boyfriend, Darian Simon, while they were walking their dog outside of an apartment complex on June 10, 2020.

Isabella Thallas

(credit: Thallas Family)

Simon told police the shooter yelled at them about the dog before he opened fire with an AR-15. Simon was shot twice but survived.

READ MORE: Isabella Thallas' Family Continues To Wait For Justice After Court Date Continued For Murder Suspect Michael Close

Michael Close (credit: Denver)

Ana Thallas, mother of Isabella Thallas, told CBS4 she was upset by the plea.

“This is so heartbreaking and disturbing,” she said on Monday. “Michael Close knew the difference between right and wrong and expressed that, and remorse, prior to my daughter’s murder and after her murder.”

READ MORE: Family, First Responders Dedicate Bench To Isabella Thallas

Close, 36, is facing 22 counts, including first-degree murder, prohibited use of a large-capacity magazine, prohibited use of a weapon, and crime of violence.

According to the Denver Police Department, Close, a friend of a Denver police officer, took the rifle from the officer’s home without the officer’s knowledge or permission. Upon learning his rifle was missing and that it may have been used in the homicide, the officer notified investigators that the rifle belonged to him. The rifle was not issued by the Denver Police Department.

Isabella Thallas

(credit: Thallas Family)

The family has been working with the city to find a space somewhere near the scene where they can build a dog park and sitting space in memory of Isabella.


Anica Padilla