Those cops must have been real fearful for their lives. After all, it appears the suicidal man was laying in a bed with a knife. Obviously a real threat.
I envision it going something like this: "Drop the weapon." Man continues to hold knife while laying in bed. BLAM, BLAM, BLAM!
Of course, we'll be cautioned to not jump to conclusions and wait until the cops' actions are declared a justified use of force. Nothing to see here... move along.