The Sundance Channel premieres the documentary series “No One Saw a Thing” this week. The subject is the murder of Ken Rex McElroy; old-school Missouri news followers will recall he was the town bully of Skidmore (in the very northwest part of the state), gunned down in broad daylight with 50 to 60 bystanders who swore they didn’t see “a thing.”

“Town bully” is too easy a term. McElroy shot people. Rustled livestock. He burned down the houses of people who slighted him. Allegedly, he raped a 13-year-old girl and then married her to keep her from testifying. Maybe “chronic criminal” is better. Then again, he was charged more than 20 times and was only found guilty once. He was out on bond when the murder happened. As an aside, his lawyer is my new hero.

Or maybe McElroy is a “monster.” That word works too. But filmmaker Avi Belkin never lingers too much on McElroy. A perverse trend in true-life crime stories is their tendency to focus on the murder rather than the victim. Even when the victim is as compellingly unsympathetic as he is here, “No One Saw a Thing” falls into the pattern of exploring who committed the deed.

Then again, as this documentary points out, several other media outlets have explored the same question with little luck. The only person who says she knows who did it was Trena McElroy, the above-mentioned child bride, sitting in the passenger seat when her husband died. But no one would cooperate, and the conspiracy lives to this day.

Over the course of the documentary’s six segments, the “who” question is brushed aside for the “why.” The filmmaker argues there’s something corrosively violent about Skidmore’s history, manifested by McElroy and amplified by the vigilante nature of his death. The town suffered further horrific acts as a result of the collective agreement to condone McElroy’s demise.

A provocative theory, if a little Old Testament for my taste. One might argue the rash of violence stems from mental illness that is not treated as seriously in a tight-knit community. Or that God-fearing folks repress their worst impulses until they burst out at the seams. But “No One Saw a Thing” isn’t my documentary to make. The concept of violence as original sin is the basis for framing the narrative and director Belkin makes the case.

At times, the case is made languidly. One wonders whether this story needed multiple episodes to tell. But the mind does wander to small towns all over our state. The violence exploding from from time to time. The drugs. The hopelessness. What is the root of this? What can be done to stop it? If it can happen in Skidmore, the doc argues, what’s going to haunt the streets where you live?

"No One Saw a Thing" premieres at 10 p.m. Missouri time on the Sundance Channel. Learn more at www.sundancetv.com.