George Floyd was killed on video — and video, and video, and video.

The trial of former Minneapolis police officer Derek Chauvin for his role in Floyd's death this week revealed two previously unseen clips of Floyd and Chauvin: One is security camera footage from inside the small grocery store where Floyd used a counterfeit bill; the other is from Chauvin's body camera. Added to that, at least six other videos recorded parts of the deadly encounter: There are two clips from exterior security cameras on the grocery store, three from body cameras worn by the other officers involved, and, of course, the bystander footage that showed all nine minutes of Chauvin's knee on Floyd's neck.

This much documentation raises an obvious point: Don't we all know what happened? Didn't we see it with our own eyes? Isn't this trial a lot of rigmarole to reach a self-evident conclusion? "So pathetic that there is a trial to prove that Derek Chauvin killed George Floyd when there is video of him doing so," late-night comic Chelsea Handler said, adding, "Perhaps we skip trials when there is audio and video footage of the murder."

Let me propose an alternative: Perhaps we don't. And perhaps as digital surveillance expands and crime on camera becomes more common, we commit ourselves to due process and reject the epistemic arrogance and naivete required to imagine we have a right to forever alter a man's life because we think we absorbed the unfiltered truth from a camera.

In a way, the Floyd case might seem a weak example for my argument. There are so many videos, and the primary bystander footage seems so straightforward. Unsurprisingly, Handler is not alone in suggesting a trial is superfluous because the video already shows us the truth. "We're watching a trial to prove that Derek Chauvin killed George Floyd after watching a video of Derek Chauvin killing George Floyd," mused one viral tweet. "This is what puzzles me," reads a reply. "We have a video. We have witnesses. The whole world knows who killed Mr. Floyd. What the hell are we doing?"

At the risk of sounding like a civics class pedant, what we're doing is not letting Chauvin's fate be decided by the state or the mob. And if you do not hold a trial, those are the alternatives. When the state does it, we call that fascism and tyranny. When the mob does it, we get witch hunts and lynching.

Our criminal justice system is very flawed, not least when the accused is a police officer. It needs significant reform at just about every step in the process: overcriminalization, policing, pre-trial detention, prosecution, jury selection, sentencing, and more. But skipping trials or turning them into rubberstamps of public opinion is not reform. It might occasionally produce a more desirable outcome in high-profile cases like this, but in the ordinary working of the system, for all the people whose story never goes viral, it will not make justice more likely.

That is true even when we have video footage.

Consider another crime on camera presently in the headlines: the horrific attack on Vilma Kari, a 65-year-old Asian woman, in New York City. Early reports of the incident, which shared a 25-second video captured by a security camera, seemed to depict a shocking case of the bystander effect. Multiple people apparently didn't bother to help Kari as she was brutally assaulted or actively made it more difficult for her to escape. "As the violent scene unfolded in Manhattan, three men watched from the lobby of a nearby luxury apartment building," said a Tuesday New York Times report. "When the woman struggled to stand up, one of the men, a security guard, closed the front door to the building."

However, as the Times reported a day later, "[e]xtended footage from the building's surveillance cameras ... told a more complicated story." In fact, only one person inside the apartment building, a delivery man who did not work there, actually witnessed the attack. Within seconds, he alerted building doormen (who were not security guards, as many initially assumed). In less than two minutes, they closed the door to the building to keep the knife-wielding perpetrator outside, then went outdoors to help the victim. They didn't call 911, but that was because they were able to flag a passing police officer.

Was their behavior exemplary or heroic? No — though I suspect most of us would be less heroic under such circumstances than we hope. But neither did they display anything like the gross apathy to evil and suffering of which they were accused on the basis of the first, shorter footage.

The temptation to treat video as a pure conveyance of truth is understandable. "A human witness can forget, get confused, or lie, but we assume that a photograph or video provides us with an accurate record of exactly what happened," writes law professor Adam Benforado in Unfair: The New Science of Criminal Injustice. "Unfortunately," Benforado continues, this is not correct:

Unless you're a film critic or an artist, you don't tend to think about how the particular camera angle or viewpoint influences the way we make sense of the scene in front of us. We get caught up in what we are seeing without considering how we are seeing it or what we might be missing. But all our seemingly neutral media hold the potential to bias assessments of what transpired and who was to blame. [Adam Benforado in Unfair]

Studies of this perspective bias show it can have enormous, unnoticed influence on how we interpret footage, Benforado recounts, and when people (e.g. jurors) are cautioned to remember their own perspective bias, they often fail.

That's not to say we shouldn't use video in criminal proceedings when it's available. It undeniably adds to our understanding of these crimes. Without footage, Chauvin might never have been charged. He might still be prowling the streets of Minneapolis, still authorized by departmental guidelines to kneel on people's necks. And maybe it's my perspective bias speaking, but in the Floyd case, I too am confident I know what I saw. I too believe that in a moral sense, and hopefully a legal one, Chauvin's culpability is clear.

Still, even the clearest footage is no substitute for due process. Viral video can't replace a trial.