In light o the Arvada shooting, I figured I'd repost this:
I've been the only plain clothes officer at an active shooting scene. It's nerve wracking.
It's difficult for many who haven't been involved in a chaotic shooting scene to really know the reality of how limited your information will be and how your own body will fail you. I know that I am very unlikely to heed verbal commands initially because I will likely be in auditory exclusion and simply not hear you. I've mentioned that after my shooting an officer I know grabbed me by the shoulder of my armor to move me as people behind me were moving up armed and I looked at him, simply saw "uniform" and then went back to the bad guy and let him move me. I knew the officer very well, but didn't take the time to process his face as my brain was busy with other things, uniform = good guy = let him move you was all that I dedicated processing power to. Think of this as the "limited processing power rule" and apply that lens to the following:
From training and experience, here's what I would recommend to prevent good guy on good guy shootings:
1) Communicate. Even if you think there is nobody to communicate with, sound off. "STOP ATTACKING THE OFFICER!" or "DROP YOUR GUN!" or whatever. There are always more 'ear witnesses' then 'eye witnesses' and sounding like a good guy will help people assume you are the good guy.
2) Put your gun away as soon as possible. ESPECIALLY long guns. Don't worry about disarming the downed bad guy. Don't even approach him, especially alone. People do this probably thinking it is safer to get it away from him. Even rookie (and sometimes not so rookie) cops get caught up in that. Leave it. Remain behind cover and watch the bad guy, no need to approach and remove the gun. If he gets back on the gun, you know he's a threat again.
3) Nobody gets shot rendering aid. If you are applying pressure to a wound and yelling for help, you are visually and audibly not a threat and "field expedient medics" will instantly be assumed "good guy" by the limited processing power rule.
4) If response is delayed and there is time, call 911 yourself. ID yourself. Now is the time to think about your wording. Do not call and say "I shot someone" and hang up. I've honest to God heard of a trainer who was telling people to call 911 and say "there's been a shooting" then hang up. That's so retarded it should be criminal to teach it to people and I can know immediately that well-meaning idiot has no experience in this realm and doesn't know what he doesn't know.
Something like "I shot someone attacking your officer at (location). The suspect is (down/fled north/whatever). I am an off duty officer (if applicable) with XXPD. I am (physical description) wearing (clothing) and will meet your officers at (location) and make myself known. My gun is (holstered/in my car/at my feet/whatever *BUT NOT IN YOUR HANDS*). Provide suspect description if suspect is still out, including last known direction of travel. Give an estimate of number of casualties and severity so EMS can be started, if applicable. If possible, have the phone on speaker and in a shirt pocket or the like once you can hear sirens. Nothing in your hands is preferable. DO NOT ASSUME THE OFFICERS KNOW WHAT YOU TOLD DISPATCH. This is a literal game of telephone, the dispatcher can mix things up, the radio may be so tied up information hasn't went out yet, an individual officer may not have heard that piece of traffic as he concentrated on negotiating a crowded intersection of oblivious idiot drivers, ec.
5) Follow instructions of uniformed officers. Now is not the time to talk or explain, it's the time to listen. This is drilled into us. It doesn't matter if you're a 20 year supervisor and the first uniformed officer is a kid 6 weeks out of the academy. He's in charge until you're detained and vetted.