If our politics has taught us anything this year, it is that emotions trump facts every time. People hold fast to their perceptions, whether real or fake, even when presented with evidence to the contrary. So it was again Friday, when the emotion of fear won out against the facts that officer Jeronimo Yanez shot and killed Philando Castile for no good reason during a routine traffic stop.

On its face, "I was afraid for my life" is a perfectly good reason. Policing can be pretty scary. But upon reviewing the dashcam video, Yanez's fear defense feels like a coverup. We see Yanez practicing his alibi almost immediately: "I told him not to reach for it!" We can equally imagine him later reciting "I was afraid for my life" 20 times in front of a mirror.

Criminologists call this a technique of neutralization, denial of responsibility and denial of the victim. And that's how the "I was afraid for my life" defense works. We are to always empathize with the police officer, never the deceased.

We're not saying Yanez wasn't afraid. He was. The problem is, fear is an emotion. Emotions are reactions to perceived or imagined stimuli, not based on logic. Yanez perceived that Castile was reaching for his gun, and thanks to the landmark 1989 U.S. Supreme Court case Graham vs. Connor, that's grounds to blindly discharge not one but seven gunshots into a car that was also transporting a 4-year-old and her mother.

Yanez's defense team made indirect reference to Graham vs. Connor, that he acted in a way that would be "objectively reasonable" to other police officers in similar situations, given the danger and stress of police work. It's funny that in no other Western democracy would this be considered reasonable. When dealing with the emotion of fear, "objectively reasonable" is really "subjectively reasonable." The lack of clear and present danger is moot in terms of an officer's legal culpability because, as the saying goes, "If men define situations as real, they are real in their consequences." In Yanez's mind, the threat Castile posed was real. The defense rests.

What is the root of all this fear? Well, Americans generally are a fearful bunch, albeit afraid of the wrong things. Fed a diet of 24-hour news and crime dramas, for instance, we come to equate people of color with drugs, violence or, worse, drug violence (you'll recall it was the stench of marijuana that alerted Yanez to Castile's supposed nefarious intent). But police are particularly susceptible to irrational fear because they are systematically trained to be fearful. Forget "Bulletproof Warrior." A Hamline University study recently uncovered that out of seven scenarios presented during a basic training on traffic stops, five were resolved with deadly force. Are we seriously telling cops that more than 70 percent of traffic stops end in a shootout?

Of course, Yanez's traffic stop did. But only because Yanez thought he saw Castile's gun. A firearm is generally cause for alarm, except that Castile was in lawful possession of it and, contrary to Yanez's view of events, "wasn't reaching" for it. Facts lost on the jury and, it seems, the NRA, which has fashioned a self-defeating pillory out of permit-to-carry laws and is conspicuous by its absence in this case.

Cops endorse Graham vs. Connor because if the law placed a heavier burden on police in deadly force scenarios, they might hesitate in the face of real danger and become another statistic. A common phrase among cops is, "Better to be judged by 12 than carried by six." We would add, even better when 12 almost always acquit, persuaded not by facts but by emotion. "Better to be without logic than without feeling," wrote Charlotte Brontë. When cops shoot first, however, it is someone else who is carried by six.

Perhaps Castile was afraid, too. There's an inherent imbalance of power between armed cops and civilians, especially black civilians in the American apartheid. Yanez was clearly on edge. And Castile had been pulled over 49 times previously, an average of about once every three months, often for minor infractions. We'll never know how he was treated during these other stops, but the odds are that he was treated badly at least once. Given that fear is also rooted in experience and past behavior is the best predictor of future behavior, there's a good chance Castile had every reason to be afraid. But we'll never know. Castile didn't live to tell the tale.

As they say in law school, "If the law is against you, argue the facts." The prosecution did its best, but the facts only ever get you so far. Think of a situation where you too had bulletproof facts and reason was on your side. Did you win the debate or the promotion or the election? We doubt it. You went in thinking there was absolutely no way the other side could say no to your perfectly constructed argument, and then that's exactly what happened. Why? Because humans are creatures of emotion, not logic.

In law school, they also say, "If the facts are against you, argue the law." The defense did precisely that, appealing to a law dripping in the emotion of fear. Yanez was acquitted not because of some conspiracy, but because the law worked as intended. The problem is that a high burden of proof in cases involving police serves only to deepen the divide between them and us. Under the current law, cops — no matter what they do — will be protected, and their fears — both real and perceived — can and will be used as justification for excessive force.

We need to change the law.

James Densley is an associate professor of criminal justice at Metropolitan State University. Jillian Peterson is an assistant professor of criminology and criminal justice at Hamline University.