'This is one that I'll remember as long as I'm alive': DPD Chief Pazen discusses Isabella Thallas murder

DENVER — Denver Police Chief Paul Pazen said the death of 21-year-old Isabella Thallas, who was shot while walking her dog in June, is one he will "remember as long as [he's] alive."

Thallas was shot and killed in Denver's Ballpark neighborhood while she was walking with her boyfriend, Darian Simon, and his dog on June 10. Simon was also shot and is recovering from his injuries. 

RELATED: Man accused of shooting Denver woman while she was walking dog faces 22 charges

According to Denver Police, the suspect, Michael Close — who has since been charged with first-degree murder — took the rifle from Denver Sgt. Daniel Politica's home without the officer's knowledge or permission. 

RELATED: Gun used to shoot woman killed while walking dog belonged to Denver police officer

Thallas mother, Ana Thallas, has since asked that Politica be fired, saying if he had been a responsible gun owner, her daughter would still be alive.

RELATED: 'It's horrific:' Mother of murder victim describes learning the gun used to shoot her daughter belonged to DPD officer

9NEWS sat down with Pazen to discuss the tragic incident.

(Editor's note: Responses have been edited for context and clarity.)

9NEWS: Could you share your personal thoughts about the case, in general?

Pazen: This case has personally affected myself, as well other officers.  Officers rushed into this situation in order to save lives and they, as well as myself, are personally hurt by this tragedy. 

This is one that I will remember as long as I’m alive.  It’s a horrible situation, a beautiful young life has been taken from us. It hurts our community and I share that hurt with the family.  

Isabella's mother is asking that Sgt. Politica be removed from the force. What are your thoughts on that request?

Pazen: We review situations and we hold officer accountable based on the laws of our city and state, as well as the rules and regulations that govern police conduct.

Are you comfortable that Sgt. Politica did not violate any department policies? 

Pazen: This is a horrible, tragic situation. We are reviewing and will continue to review policies and see if there are any violations, and we hold our officers accountable for any law violations or policy violations. There is a criminal case that is ongoing. We are monitoring the criminal case and we will continue to do that.

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