The defense began its case with fear. Attorney Eric Nelson filled the Minneapolis courtroom on Tuesday with great plumes of it: a thick, debilitating, choking cloud of fear.

Former police officer Derek Chauvin was afraid of the assembled bystanders who were shouting their concern for George Floyd, who lay face down on the ground and unresponsive under Chauvin’s weight. Chauvin was fearful that Floyd might suddenly rise up in a fit of “excited delirium,” break free of his handcuffs and, with superhuman strength, cause deadly mayhem. Chauvin was terrified that Floyd — a tall, muscular, unarmed Black man — would overwhelm him, a welterweight White police officer surrounded by three other police officers, each of them carrying a gun and trained in self-defense. Chauvin was fretful that Floyd, no longer resisting or even moving, remained an enduring threat because that’s what he had been taught to believe, and that’s what a reasonable officer would believe; and on Tuesday afternoon a witness in Chauvin’s defense said that’s what he, too, believed.

Barry Brodd was the silver-haired use-of-force expert from Bozeman, Mont., who testified on behalf of Chauvin, who is on trial for Floyd’s death in May. Brodd was the confounding human who said that pressing Floyd into the pavement for more than nine minutes while he cried out that he couldn’t breathe was not really “force” at all. This assessment was so incongruous with logic that prosecutor Steve Schleicher launched into his cross-examination with the slow, methodical patience of a lion stalking a lame antelope.

Did you say resting comfortably, or laying comfortably, resting comfortably on the pavement?” Schleicher asked.

“I was describing what the signs of a perfectly compliant person would be,” Brodd said.

So attempting to breathe, while restrained, is being slightly noncompliant?” Schleicher asked.

Brodd was the serene former police officer with no medical expertise who said that Floyd’s crying out for breath was an indication that he didn’t actually need any, which is a bit like saying that a drowning man’s calls for help are evidence that he’s treading water just fine.

Brodd came not only to validate Chauvin’s fears, but to declare them righteous and logical. Fear is a key ingredient in Chauvin’s defense. It’s the connective tissue. As a police officer, Chauvin surely has many things to cause him concern — first among them that he will not go home alive at the end of his shift. To be afraid can be a wise man’s way of staying safe.

But all fear is not equal — not in policing. Floyd’s terror at apprehension by four officers is perhaps not germane to the specific legal arguments the state is making in its case, being made in this trial, but it is there in its rawest form. His fear is evident when he’s in physical duress, of course, but it was already present — a weight that he carried around his neck, a knot that was forever in his gut, a chronic ache that was always front of mind. It was made plain from the moment he encountered the police.

It was there in 2019, when the car he was in was stopped by now-retired police officer Scott Creighton, who testified Tuesday for the defense. Body-camera footage shows Creighton approaching Floyd, who is in the passenger seat of the vehicle. Floyd begins their dialogue with a simple plea: “Don’t shoot me, man. I don’t want to get shot.”

By the time Floyd is out of the car and being placed into handcuffs, officers are having to reassure him that they do not plan to beat him up.

In 2020, when officers approached the SUV he was sitting in outside Cup Foods, they first tapped on the driver-side window with a flashlight and then with guns drawn. Floyd again opened by begging for his life, according to testimony from Shawanda Hill, who was with him. “He instantly grabbed the wheel and he was like, ‘Please, please, don’t kill me. Please, please, don’t shoot me. Don’t shoot me. What did I do to somebody? Please, please, don’t shoot me,’” Hill said.

Floyd is certainly not alone with the worry that lives inside him. A similar foreboding is there in video recently made public that shows Caron Nazario, a second lieutenant in the Army, during a December traffic stop in Windsor, Va. Nazario, who is Black and Latino, has both hands thrust outside the windows of his SUV. Officers have their guns drawn and are ordering him out of the car. To comply, he would have to move his hands to unbuckle his seat belt and reach for the door handle. Nazario is frozen in place. He tells the officers that he is “honestly afraid to get out.” And Officer Joe Gutierrez responds, “Yeah, you should be!”

To be afraid can be a wise man’s way of staying safe.

Fear isn’t the result of these police encounters. All too often, it’s the starting point. The fear rises like steam. Some officers breathe that in and then stand a bit taller. Their chest puffs up and they scream louder. They bellow expletives. That’s what Gutierrez did in Virginia after Nazario shuddered in the face of the weapons pointed at him. Gutierrez unleashed pepper spray. He yelled even more. Nazario is suing. Gutierrez has been fired, but not before he was sated on Nazario’s fear.

Was it nourishing? These moments of terror happen so often that one might assume that police officers grow stronger, more invincible each time they gnaw at the soul of some Black or Brown citizen who has committed a minor offense — or no offense at all — and the arrival of a police officer fills them with palpable dread. Some police officers have gotten fat off the anxieties of entire communities and multiple generations.

But those who feed ravenously at the trough of fear can also wind up full of cowardice and hysteria. And instead of keeping them safe, fear ultimately makes them choke.