(let me first say that yes many cops are just fr racist)
but i think theres smth to be said abt the issue being area based too. if theyre going into a more crime ridden area (usually somewhere socio-economic disadvantages and predominately black or his
hispanic) they get all tense and act way different than they would in gated neighborhood
its partially the racism and partially them thinking anyone who lives in that area is of potential threat to them