This isn’t a new story—it happened a year ago tomorrow—but it’s one of the more interesting claims I’ve seen by a police officer involving a negligent discharge shooting of a suspect.

Matthew Hovland-Knase, 22, of Bloomington, led police on a chase at 3 a.m. on June 20 that reached speeds of almost 100 miles per hour before stopping at Eden Prairie Road near North and South Lund roads. Sgt. Lonnie Soppeland got out of his squad car with his gun drawn — protocol for high-risk stops, he told investigators — but the gun went off, shooting the motorcyclist’s arm.

According to documents released to the Star Tribune on Friday by the Hennepin County Sheriff’s Office, Soppeland told investigators that firearm training earlier that month contributed to the unintentional discharge due to the muscle memory of squeezing the trigger.

“My plan was to hold the suspect where he was until back up arrived,” he told investigators three days later. “ … It was not my conscious choice to discharge my firearm. This all happened very fast, maybe within a matter of a second. I could feel the effect of the adrenaline.”

Soppeland immediately holstered the gun and ran to Hovland-Knase to render first aid and call for an ­ambulance.

Sgt. Soppeland’s explanation of what happened when he drew his gun is telling.

It seems certain that when Sgt. Soppeland drew his weapon after the extreme stress of a chase that topped more than 100+ MPH and conducted a felony stop, his finger went on the trigger of his pistol and took the slack out of it. As soon as he brought his other hand on the gun, it was enough of a jolt to break the shot, putting a bullet into Hovland-Knase’s left arm.

To his credit, Soppeland immediately rushed to render aid to Hovland-Knase and appears to have been direct and honest during the investigation, cooperating and taking responsibility for his actions.

And yet, there’s this.

Sgt. Soppeland may very well believe that his training had something to do with this negligent discharge, but I’m confident that is not the case, based on the hundreds of hours of formal training I’ve had with handguns.

Back when double-action revolvers were the primary police sidearm, some departments taught “on target, on trigger,” meaning that as you aimed at a suspect, you put your finger on the trigger of your weapon. This seems to have worked reasonably well when officers had a long, heavy double-action trigger pull to break a shot.

When departments switched over to striker-fired pistols with comparatively light and shorter trigger pulls, officers in departments that had ingrained “on target, on trigger” saw a dramatic increase in the number of negligent discharges.

For 30 years or more, the standard practice has be for officers to place their trigger finger on the slide or frame of semi-automatic pistols until the moment they are ready to fire, and in situations like this where an officer is attempting to take a two-handed firing stance, your finger doesn’t go near the trigger until you’ve established a firm two-handed grip on the gun and you’ve pressed out.

But…

No matter the level of training, about 20-percent of officers filmed during high-stress simulator training seem to instinctively put their finger on the trigger, regardless of their level of training.

I’m 100% confident that Sgt. Soppeland was not taught to put his finger on the trigger of his gun before he established a two-handed firing grip, because that is not what officers are trained to do. You’re taught to obtain a grip, press out, and then put your finger on the trigger and fire if the situation dictates shooting.

He can’t fairly blame “muscle memory”—which many experts claim simply doesn’t exist—when he wouldn’t have been trained that way.

It is far more likely that Sgt. Soppeland was simply under high amounts of stress and his finger instinctively went to his trigger and took up the slack until he hit “the wall,” and the jolt of his second hand coming onto the gun broke the shot.