The left wants to get rid of our system of local police and sheriffs and replace it with federal police. Having local police is a bulwark against federal tyranny. In training, police (at least in some cases) are asked if they would obey the president if he ordered them to arrest someone. The correct answer is “no”.
All totalitarians know this.
Even the Chinese Army troopers who committed the Tianaman(sp?) square massacre was brought in from far away provinces. Similarly last century when the British government needed to crack down on unruly miners, they brough in police from elsewhere.
There is some “protection” in the fellowship between the local citizens and the local police.