Jerry Holt / Star Tribune / Getty

The most unsettling reporting I have done on the subject of human necks was in March 2014 in the Central African Republic. I was interviewing a militiaman who said he had killed Muslims, and offered to demonstrate. He then took out a blade and posed with his friend, placing the cutting edge against the man’s throat. What gave me the creeps was not the knife hand but the other one. His fingers pulled taut the skin of his friend’s neck, the better to ensure a firm cutting surface for the blade. The move was instinctive—and to me familiar, from having butchered animals. If you don’t pull the flesh tight, your knife doesn’t bite cleanly, and you make a mess of things. I saw that finger and thought: This man really has done this before.

A close relative of that thought is what many Americans have experienced in the past few days, contemplating what diseased mind could place a knee on the neck of another human being and press until the man died. The tactile experience of kneeling into a human neck is not familiar to most people, and the video of Derek Chauvin, then a Minneapolis police officer and now a civilian charged with murder, kneeling into the neck of George Floyd is about as disturbing as anything most of us have ever seen. Even I—a veteran watcher of snuff films—cannot recall ever seeing someone killed in this way. (The Islamic State would stab people slowly in the heart, or smoosh them with tank treads, or burn them alive.) The only thing that has brought me close to this form of killing is Joshua Oppenheimer’s singular film The Act of Killing, about executioners in Indonesia with extensive experience strangling their victims.

Oppenheimer asked killers to reenact their executions, to simulate their own violence. You can learn a lot from being placed in the physical arrangement of the act you are trying to understand. All commercial pilots know this: Sophisticated flight simulators enable them to experience the physical reality of certain uncommon cockpit events—wings breaking apart, engines failing, hydraulics going haywire—which allows the pilots to feel the precise number of pounds of pressure it might take to, say, lean into or pull back on a reluctant yoke.

To understand what happened to Floyd, I tried to simulate the position of his killer. My crude simulator involved a stopwatch and kneeling on a rolled-up yoga mat, on top of which I placed a gelatinous pad used by medical students to imitate human skin. (I have these things in my house.) A yoga mat and a fake-skin pad are no substitute for the neck of a dying, pleading man, and thank goodness for that. I used the times noted in the coroner’s report: five minutes and 53 seconds of kneeling before officers declared that Floyd was unresponsive, followed by two minutes and 53 seconds of continued pressure. That totals just less than nine minutes.

At about 20 seconds (far sooner than I had expected), my knee started to throb. Normally when you kneel, you get to shift your weight a little, to give each knee a little vacation from the stress. If you are trying to hold down someone who does not want to be pinned, you probably want to drive your weight hard into one vulnerable place—and if you let up, you will assume that he’ll wriggle around and make you start all over again. The steady pressure builds.

At about one minute, the throb turned decisively to pain and stress. I could feel my muscles rebelling, asking me why I was doing this. Standing on one foot for more than a brief period will have the same effect. Your body knows that you are pulling a stunt, that the posture is needless and uncommon.

The next three minutes felt much longer—though Chauvin, under the influence of adrenaline, perhaps experienced it much differently, as much less than three minutes. This was the time during which Floyd transitioned from begging, gasping, and drooling to unconsciousness. The physicality of kneeling was at that point not just fully painful but unfamiliar. Normal people never do this. The closest experience I’ve had is again from the world of livestock—holding down a calf (“200 pounds of animated hamburger,” as the rodeo announcers used to say in Texas) while it gets vaccinated and castrated, and resists about as much as you might expect.

Now I was more than halfway to the time at which Floyd stopped responding, and Chauvin’s knee, according to the charges, transformed from a tool of submission into a murder weapon. I weigh more than 200 pounds. I could imagine pinning a man with my knee, using all that force, to hold him still if necessary. But any sentient moral creature should feel that the pressure, applied like this, is an attempt to maim. The revulsion is natural: Whatever I have been leaning into is by now broken. The joint is torqued and sprained, the fascial tissue smeared or torn, the skin and muscle bruised, a major organ permanently injured or worse.

At five minutes and 53 seconds, my knee was numb. It stayed that way for the remaining minutes, and I don’t see how anyone could remain in that position, knee driven into a by-now-inert mass of humanity, unless he was at best totally indifferent to the person’s survival.

I picked up my knee, stood up with the support of a bathroom sink, and saw that the rolled-up yoga mat had gone flat in the middle, like a toothpaste tube that has been hit with a karate chop.

I have become skeptical of what (I think) I see in photos or on video. That skepticism is a civic duty and a professional one. But the evidence in this video is abnormally clear, as well as consistent with a sad record of violent policing in this country. “Police are trained that this type of restraint with the subject in prone position is inherently dangerous,” the criminal complaint against Chauvin says. I am glad to know the police provide this training, and I hope that they continue doing so. They might also consider screening candidates to the force to confirm that the thought of administering this type of restraint, for more than eight uninterrupted minutes, is enough to elicit some scruples.

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