Why Cops Shoot Unarmed Black People
The policeman's best defense might be "my amygdala made me do it." The brain has at least two circuits for processing threats. In the first, the information goes to the amygdala, a threat is registered, and sent to the prefrontal cortex for further processing. There the threat is evaluated and instructions are sent to the motor neurons for a response. In the second, the alarms that go off in the amygdala are so strong that prefrontal processing is skipped, and the motor neurons are activated immediately, saving roughly 700 milliseconds. The penalty for speedy evaluation is loss of accuracy: that cell phone or wallet might be evaluated as a gun. This kind of fatal error probably happens more to blacks because policemen - even black policemen - find them more threatening and hence their amygdalas are more excited.
Logically, when the amygdala wants to mobilize a behavior— say, fleeing— it talks to the frontal cortex, seeking its executive approval. But if sufficiently aroused, the amygdala talks directly to subcortical, reflexive motor pathways. Again, there’s a trade-off— increased speed by bypassing the cortex, but decreased accuracy. Thus the input shortcut may prompt you to see the cell phone as a gun. And the output shortcut may prompt you to pull a trigger before you consciously mean to.
Sapolsky, Robert M.. Behave: The Biology of Humans at Our Best and Worst (p. 58). Penguin Publishing Group. Kindle Edition.It should be obvious that those 700 milliseconds are often crucial - if batters waited for the prefrontal cortex to evaluate, no hitters would be more common than hits. Similarly for soldiers at war.
So what can be done? Don't be racist style training is probably a waste of time. So, probably, are draconian punishments for perpetrators. Detailed training on how to make stops and arrests isn't. If the suspect isn't actively shooting people, gather information and consciously evaluate threats before putting yourself and the suspect at risk. If you are going to ask a scary suspect for license and registration, ask him where it is first. I'm sure there are other measures that can be considered, but situational training is crucial - and much of it can be done on simulators. Trigger happy cops can be retrained, assigned to desk duty or dismissed. I haven't yet read enough of Behave to know if Sapolsky has better ideas.