Because it is not actually proven that it was a cop and the St Paul Police Department says it wasn't him but they did not offer up any kind of conclusive evidence that it wasn't.
From the last link that I posted:
https://theguardiansofdemocracy.com/...3JSDJfojgWFMp8
“RUMOR CONTROL…We are aware of the social media post that erroneously identifies one of our officers as the person caught on video breaking windows in Minneapolis,” the St. Paul Police Department’s official Twitter account tweeted. “We’ve seen it. We’ve looked into it. And it’s false.”
“So we also want to be perfectly clear about this: The person in the video is not our officer,” the statement added. “We don’t know who that person is, but we hope he’s identified and held accountable for his actions. Our officer? He’s been working hard, keeping people and property safe, and protecting the right to peacefully assemble. It’s sad that people would post and share this untrue information, adding more confusion to an already painful time in our community.”
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So, they don't say where the cop was or what he was actually doing at the time, just that it wasn't him.
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