Once again, a hard-to-watch video leaves us shocked by the behavior of local police. And, once again, the use of force makes a community question whether some cops are more oppressors than public servants.

This time the damning video was shot on a St. Paul sidewalk in broad daylight. On Aug. 28, St. Paul police officer Jesse Zilge was recorded stopping and arresting Eric Hightower. The video was posted on YouTube, where anyone could watch Zilge kick Hightower in the chest and, along with a second officer, slam his head onto a car hood.

St. Paul police Chief Thomas Smith put the officers on leave and asked his internal-affairs unit to investigate. Citizens can hope that the internal unit will do what's right, but there is understandable skepticism whenever police are asked to police themselves. Investigations such as this are more credible if civilian review is part of the process.

The St. Paul case also demonstrates the importance of selecting officers with the right temperament for the job and training them well. After the 1991 Rodney King beating in California and the 2006 Derryl Jenkins assault in Minneapolis, officers ought to fully understand the damage done by brutality. They should be even more inclined to think twice now that dash cams are mounted on many squad cars -- and because almost everyone carries a smartphone.

Street-level law enforcers also need to realize how much their misdeeds can cost a city -- and the taxpayers who cover their salaries. King and Jenkins received seven- and six-figure settlements, respectively.

As is often the case, the victim in the St. Paul video is no angel. Hightower has a history of run-ins with the law and was arrested last month on allegations of threatening his ex-girlfriend and causing property damage.

However, as the video clearly shows, he was not resisting when a person on the street started taping the arrest. He had been sprayed with a chemical irritant and was lying on the ground. Hightower was asking the officer what he did, but did not make any physically threatening moves. And, based on the number of voices heard on the video, there were lots of witnesses.

But that didn't stop Zilge from kicking Hightower while he was on the ground, slamming his head onto the hood of the squad car and repeatedly jerking him around by the hair while he was handcuffed.

The fact that Zilge had been disciplined for using excessive force when he worked for another Twin Cities-area police force raises questions about how well he was vetted before being hired in St. Paul.

The best cops understand that some of their finest work is done in cooperation with the communities they serve. Few strong cases against criminals hold up without the eyes and ears of witnesses. Citizens gladly work with cops to solve crimes when they have confidence that the officers are on their side.

But the type of video evidence seen in the King, Jenkins and Hightower cases undermines that confidence. If an officer can so recklessly kick someone in front of witnesses and a camera, how often do those types of attacks happen at night when cameras aren't rolling?

Over the years, St. Paul police chiefs and their staffs have worked diligently to build relationships with communities they serve. To maintain those gains, it is imperative that the kind of brutality seen in the Hightower case is never tolerated, and that the offending officers are appropriately disciplined.

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