In the hours after the first reports of a shooting involving police yesterday at Hoyt Arboretum, news outlets used caution in referring to the incident. We didn't actually know that an officer shot somebody until around 5 pm.
At that time, I changed our headline from "Police Involved in Shooting at Hoyt Arboretum" to "Police Shoot Man at Hoyt Arboretum." Here's a roundup of how other news outlets are wording the incident, as of this morning. Only KGW came right out and used the word "kill" in the active voice: