The tenets of police ideology are not codified or written down, but are nonetheless widely shared in departments around the country.

The ideology holds that the world is a profoundly dangerous place: Officers are conditioned to see themselves as constantly in danger and that the only way to guarantee survival is to dominate the citizens they’re supposed to protect. The police believe they’re alone in this fight; police ideology holds that officers are under siege by criminals and are not understood or respected by the broader citizenry. These beliefs, combined with widely held racial stereotypes, push officers toward violent and racist behavior during intense and stressful street interactions.

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