Sean Sant declined to prosecute the Pasco officers based upon state law — “ … peace officer shall not be held criminally liable for using deadly force without malice and with a good faith belief that such act is justifiable.”
This means a policeman will never be held liable, as long as he remembers to use the magic words, “I believed serious physical harm was imminent.” (And these officers had eight weeks to learn the magic words before they were interviewed).
But what is “serious physical harm?” I find no definition in Washington law. Elsewhere, it may be restricted to injuries that create a substantial risk of death, cause permanent disfigurement or prolonged functional impairment. Zambrano-Montes had a 3-pound rock. Too heavy to throw with velocity, so a lethal blow is improbable. Yes, getting hit will hurt and cause an injury, but seems unlikely to disfigure or impair.
I don’t believe these are rogue cops. Police training is often skewed to emphasize what force is authorized. Would I fear someone with a rock? Yes, but I expect their training to teach officers to overcome this natural fear and defuse the situation so that shoot-to-kill is not necessary. System failure.